Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiMC LC Trang MC LC .........................................................................................................1 LI NI U....................................................................................................5 PHN I. TNH HNH CHUNG..........................................................................6 Chng 1. Tnh hnh chung ca khu vc............................................................6 1.1. iu kin t nhin ca khu vc ...............................................................6 1.1.1. V tr a l v a hnh t nhin .......................................................6 1.1.2. Tnh hnh kh tng thu vn ...........................................................7 1.1.3. Tnh hnh a cht th nhng ca khu vc...................................14 1.2. Tnh hnh kinh t c hi ca khu vc....................................................16 1.2.1. Phn khu hnh chnh v dn c......................................................16 1.2.2. Hin trng kinh t ...........................................................................17 1.2.3. Yu cu pht trin kinh t trc mt v lu di i vi ngnh nng lm nghip ...........................................................................................................21 1.3. Hin trng thu li ca khu vc .............................................................23 1.3.1. Hin trng phn vng ti ca khu vc..........................................23 1.3.2. Hin trng h thng ti trong khu vc..........................................24 1.3.3. Kt lun v yu cu thu li i vi khu vc .................................25 PHN II.TNH TON CC CH TIU K THUT ...................................26 PHC V CHO LP D N U T..........................................................26 Chng 2. Tnh ton cc c trng kh tng thu vn....................................26 2.1. Mc ch, ngha v ni dung tnh ton...............................................26 2.1.1. Mc ch, ngha ...........................................................................26 2.1.2. Ni dung tnh ton ..........................................................................27 2.2. Tnh ton ma ti thit k....................................................................27 2.2.1. Mc ch, ngha v ni dung tnh ton........................................27 2.2.2. Chn trm tnh ton v tn sut thit k cho ti...........................27 2.2.3. Chn thi on tnh ton v phng php tnh ton.......................28 2.2.4. Tnh ton m hnh ma v thit k .................................................28 2.3. Tnh ton ma nm ca khu vc...........................................................33 2.3.1. Mc ch, ngha v ni dung tnh ton........................................33 2.3.2. Chn trm tnh ton ........................................................................34 2.3.3. Tnh ma nm trung bnh nhiu nm Xo........................................34 2.4. Tnh ton lng ma mt ngy max .....................................................34 2.5. Tnh ton bc hi v bc hi chnh lch khi c h...............................34 2.5.1. Mc ch, ngha v ni dung tnh ton........................................34 2.5.2. Chn trm tnh ton ........................................................................35 Sinh vin thc hin: Trn Nam Hi Lp: 47N11Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi2.5.3. Tnh ton bc hi trn khu ti......................................................35 2.5.4. Tnh ton bc hi chnh lch khi c h ..........................................35 2.6. Tnh ton cc c trng kh tng khc .................................................37 2.6.1. Nhit ...........................................................................................37 2.6.2. m..............................................................................................38 2.6.3. Tc gi .......................................................................................38 2.6.4. S gi nng....................................................................................38 2.7. Tnh ton cc c trng thu vn ...........................................................38 2.7.1. Phn tch ti liu dng chy v chn trm tnh ton........................38 2.7.2. Tnh ton dng chy nm ng vi tn sut thit k ........................39 2.6.3. Tnh ton dng chy l...................................................................43 2.6.4. Tnh ton bn ct............................................................................46 Chng 3. Tnh ton yu cu nc ca khu vc ...............................................48 3.1. Mc ch, ngha v ni dung tnh ton .................................................48 3.1.1. Mc ch, ngha............................................................................48 3.1.2. Ni dung tnh ton ..........................................................................48 3.2. Tnh ton ch ti cho cc loi cy trng.........................................48 3.2.1. Mc ch, ngha v ni dung tnh ton........................................48 3.2.2. Nguyn l tnh ton .........................................................................49 3.2.3. Cc ti liu dng trong tnh ton .....................................................49 3.2.4. Xc nh lng bc hi mt rung..................................................52 3.2.4. Tnh ton ch ti cho la..........................................................53 3.2.5. Tnh ton ch ti cho cy trng cn (cy ng v ng) ...........61 3.2.6. Tnh h s ti v gin h s ti cho cc loi cy trng ..........63 3.3. Tnh yu cu nc cho sinh hot............................................................65 3.4. Xc nh yu cu nc cho ton h thng..............................................66 3.4.1. Mc ch, ngha............................................................................66 3.4.2. Ni dung tnh ton ...........................................................................66 PHN III. XUT PHNG N V TNH TON .................................67 PHNG N ...................................................................................................67 CHNG IV. XUT PHNG N B TR H THNG TI CHO KHU VC ...................................................................................................................67 4.1. Mc ch, ngha ...................................................................................67 4.1.1. Mc ch .........................................................................................67 4.1.2. ngha ...........................................................................................67 4.2. Phn tch cc iu kin t nhin, hin trng ti ca khu vc.............. 67 4.2.1. Phn tch cc iu kin t nhin ca khu vc.................................67 4.2.2. Hin trng cp nc ca khu vc...................................................70 4.3. xut phng n ngun nc v bin php cng trnh trong khu vc70 4.3.1. xut phng n v ngun nc..................................................70 Sinh vin thc hin: Trn Nam Hi Lp: 47N12Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi4.3.2. xut bin php cng trnh trong khu vc ...................................70 4.3.3. Xc nh nhim v ca cng trnh ..................................................71 4.4. Phn tch v chn phng n b tr cng trnh u mi ........................72 4.4.1. Chn tuyn p chnh......................................................................72 4.4.2. Chn tuyn p ph ........................................................................76 4.4.3. Chn phng n b tr cng ly nc............................................76 4.4.4. Chn phng n b tr trn x l ....................................................78 4.5. Phn tch v chn phng n b tr h thng knh v cng trnh trn h thng .......................................................................................................................80 4.5.1. Nguyn tc b tr knh ti............................................................80 4.5.2. Phn tch v chn phng n b tr h thng knh..........................81 CHNG V. TNH TON PHNG N......................................................83 5.1. Mc ch, ngha ...................................................................................83 5.1.1. Mc ch .........................................................................................83 5.1.2. ngha ...........................................................................................83 5.1.3. Ni dung tnh ton ..........................................................................83 5.2. Tnh ton qu trnh lu lng yu cu u h thng ...........................83 5.2.1. Mc ch, ngha............................................................................83 5.2.2. Cc ti liu dng trong tnh ton....................................................84 5.2.3. Ni dung tnh ton ...........................................................................85 5.3. Tnh ton mc nc yu cu khng ch ti t chy u h thngyc.................................................................................................................................89 5.3.1. Mc ch, ngha............................................................................89 5.3.2. Ni dung tnh ton ...........................................................................89 5.4. Tnh ton iu tit h ............................................................................90 5.4.1. Mc ch, ngha............................................................................90 5.4.2. Ni dung tnh ton ...........................................................................91 PHN IV. THIT K CNG TRNH U MI .........................................108 CHNG VI. THIT K NG TRN X L......................................108 6.1. Mc ch, ngha v ni dung tnh ton..............................................108 6.1.1. Mc ch, ngha .........................................................................108 6.1.2. Ni dung tnh ton ........................................................................108 6.2. Cc ti liu tnh ton v hnh thc trn ................................................108 6.2.1. Cc ti liu dng trong thit k .....................................................108 6.2.2 Phng n b tr v chn hnh thc trn .........................................108 6.3. Xc nh kch thc trn c bn cang trn ................................109 6.3.1. Tng cnh hng dng ...............................................................109 6.3.2. Ngng trn..................................................................................110 6.3.3. Dc nc .......................................................................................110 6.4. Tnh ton thu lc ca ng trn......................................................111 Sinh vin thc hin: Trn Nam Hi Lp: 47N13Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi6.4.1. Tnh ton thu lc on thu hp ...................................................111 6.4.2. Tnh ton thu lc dc nc on c chiu di khng i ............ 113 6.5. Tnh ton knh dn h lu....................................................................118 6.5.1. Thit k knh .................................................................................118 6.5.2. Kim tra iu kin khng xi ca knh .........................................119 6.6. Tnh ni tip v tiu nng chn dc nc.........................................119 6.6.1. Mc ch tnh ton tiu nng........................................................119 6.6.2. Hnh thc tiu nng .......................................................................120 PHN V. TNH TON KINH T..................................................................123 CHNG VII. TNH TON KINH T CA D N..................................123 7.1. Mc ch, ngha v ni dung tnh ton..............................................123 7.1.1. Mc ch .......................................................................................123 7.1.2. ngha .........................................................................................123 7.1.3. Ni dung tnh ton ........................................................................123 7.2. Nguyn l tnh ton.............................................................................123 7.3. Tnh ton cc ch tiu kinh t..............................................................124 7.3.1. Cc khi nim c bn v phng php tnh ton..........................124 7.3.2. Tnh ton cc ch tiu kinh t........................................................126 7.4. Kt lun v kin ngh ..........................................................................130 Sinh vin thc hin: Trn Nam Hi Lp: 47N14Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiLI NI Ut nc ta ang ho mnh vo qu trnh hi nhp v pht trin kinh t ca khu vc v th gii. Pht trin v nng cao hiu qu sn xut nng nghip theo hng sn xut hng ho, bo m an ninh lng thc quc gia l mt trong nhng mc tiu quan trng m ng v nh nc ta ang phn u thc hin. c th pht trin v nng cao hiu qu sn xut nng nghip th nhim v t ra i vi cng tc thu li l cn gii quyt mt cch ti u cc nhu cu v ti v tiu ca ngnh nng nghip. V vy vic lp v xy dng cc d n v thu li trong c cc h thng ti, tiu cho cc vng min trn c nc, bo m s khai thc hp l, hiu qu v bn vng ti nguyn t, nc v iu kin t nhin ca tng vng l vn c ngha quyt nh.c nhn ti tt nghip vi nhim v Lp d n u t v xy dng h thng ti h P1 tnh Bnh Thun, vi s hng dn ca PGS.TS. Phm Ngc Hi. Sau thi gian nghin cu, tham kho cc ti liu c lin quan v tnh ton nay em xin trnh by nhng ni dung c bn ca d n lp vi mong mun p ng c cc yu cu ra.Do kin thc v kinh nghim thc t cn hn ch nn khng trnh khi nhng thiu st. Em rt mong nhn c s ng gp v ch dn ca cc thy c.Em xin trn trng cm n!H Ni, thng 5 nm 2010.Sinh vin thc hin.Trn Nam HiSinh vin thc hin: Trn Nam Hi Lp: 47N15Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiPHN I. TNH HNH CHUNGChng 1. Tnh hnh chung ca khu vc1.1. iu kin t nhin ca khu vc 1.1.1. V tr a l v a hnh t nhin 1.1.1.1.V tr a l Khu ti P1 l vng ng bng ln nht ca tnh Bnh Thun, thuc a phn huyn Hm Thun Bc, ko di t x Hm Tr pha Bc xung ti thnh ph Phan Thit pha Nam, t sng Khan pha ng n gip ng ng mc +50 pha Ty.Ta trung tm khu ti: Kinh ng: 1088; V Bc: 114Hm Thun Bc l huyn nm v tr trung tm tnh Bnh Thun, c to a l: 111240 n 113932 v bc; 1075000 n 1081058 kinh ng.Bn hnh chnh huyn Hm Thun BcPha Bchuyn gip vicaonguynDi Linh, phanam gip vithnh ph Phan Thit, pha ng gip vi huyn Bc Bnh v pha ty gip huyn Hm Thun Nam v huyn Tnh Linh.Nh vy, Hm Thun Bc c v tr a l kh thun li, nm gn trung tm kinh t, hnh chnh ca tnh l thnh ph Phan Thit, c khu cng nghip Bnh Thun, gn Sinh vin thc hin: Trn Nam Hi Lp: 47N16Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hitrung tm kinh t ln th hai ca t nc (Thnh ph H Ch Minh), thuc tam gic pht trin kinh t min ng Nam B, gn vng kinh t trng im pha nam... nn cng c nhiu thun li trong vic pht trin v hi nhp vi nn kinh t quc gia. Do huyn d dng nng cao kh nng thu ht u t trong cng nh ngoi nc, tip cn vi cc thnh tu khoa hc k thut tin tin cng nh vn o to v pht trin ngun nhn lc a phng pht trin kinh t.1.1.1.2. c im a hnh, a mo 1. a hnh Lu vc sng Quao nhn chung c a hnh thp dn t Ty sang ng vi nhiu dy ni ca ng Trng Sn n lan tn ra bin. V th a hnh b chia ct thnh nhng vch dc, nhng thung lng su v cc ng bng hp. Pha ty v ty bc l nhng dy ni cao t 300 1000 (m). Do a hnh nh vy nn h thng sng sui y phn ln l ngn v c dc ln.Cao trnh rung t trong khu tichnh nhau kh ln, t cao +50 (m) pha Ty - Ty Bc xung dn cao + 5 m n + 10 m pha ng ng Nam.Din tch khu vc o trn bn t l 1/10.000 phn b theo cao nh sau :Bng 1.1. Phn b din tch huyn Hm Thun Bc theo cao .Cao ( m ) < 10 15 20 25 30 35 40 45 50Din tcht nhin ( ha )2196 5694 6199 8843 11253 13744 16263 18694 20724Thc tcn ti (ha )1740 3000 4300 5750 6830 7700 8200 8530 81402. a mo Khu vc c 3 dng a mo chnh: - Vng i ni v vng bn sn a pha bc v ty bc l cc khu vc pha ty ng st Bc Nam bao gm cc x: Hm Tr, Hm Ph, Thun Ho v 4 x vng cao ng Giang, ng Tin, La D v Thun Minh.- Vng ng bng ph sa ven sng: Bao gm cc x nm dc theo Quc l 1A v Quc l 28. y l vng c a hnh tng i bng phng v t ai mu m thuc loi bc nht ca tnh Bnh Thun.- Vng cn ct ven bin pha nam v ng nam: Phn b pha ng Quc l 1A. Bao gm cc x: Hm c, Hng Sn,Hng Lim v Hm Nhn.1.1.2. Tnh hnh kh tng thu vn 1.1.2.1. Tnh hnh kh tng Sinh vin thc hin: Trn Nam Hi Lp: 47N17Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi1. Mng li trm kh tng Lu vc sng Quao v vng ln cn c cc trm kh tng: Phan Thit, Phc L, Sng Ly, Bo Lc, T Pao, Di Linh.... nh hng ca cc khi khng kh gy ma khc nhau trong tng thi k v s bin ng v iu kin a hnh ko theo s thay i v cc yu t kh tng, r nt nht l ma tng khu vc. Lng ma ph thuc vo cc yu t i kh hu trn din rng do cc khi khng kh ln gy ra, ngoi ra cn ph thuc vo cc yu t vi kh hu do bin ng a hnh mt cch cc b nn din bin ma theo khng gian kh phc tp. Do , khi tnh ton phi chn nhng trm c bn tho mn cc iu kin : C ti liu di, cht lng ti liu tt, phn nh ng tnh cht ma c trng cho khu vc.2. Cc yu t kh hu a. Nhit : Ch nhit trn lu vc phn nh c th chung ca min ni, nhng cng c nt ring ca tng vng. V mt v tr, khu ti P1 do gn bin hn cc khu vc thuc lu vc sng ng Nai, cao gim nn nn nhit c cao hn. Nu ly trm Phan Thit l trm gn khu ti nht th c cc c trng v nhit nh sau:- Nhit trung bnh nm t : 26,8C.- Nhit trung bnh thng cao nht: 28,8C.- Nhit trung bnh thng thp nht : 25C.S dao ng nhit gia ngy v m cng c s khc bit. Nu nh s chnh lch vng ni pha trn t 8C th vng Phan Thit ch t 3C 4C.Bng 1.2. Nhit trung bnh, max, min ti trm Phan Thit.Thng1 2 3 4 5 6 7 8 9 10 11 12Trung bnhTTbnh25,125,326,628,428,827,827,227,126,927,126,425,126,8Tmax32,933,732,437,237,235,83534,235,533,834,233,634,6Tmin1817,318,322,622,921,821,623,222,421,619,218,220,6b. Bc hi:Ti lu vc sng Quao cng khng c iu kin o bc hi ti ch nn y phi ly bc hi ti trm Phan Thitlm cn c. Ta thy rng trong khu vc thng ngun sng Quao v vng ven Phan Thit c s khc nhau. Nhng ni ma nhiu nh vng Bo Lc th lng bc hi lu vc thp nht, ch t 1,77 (mm/ngy - m). Ni ma t nh Phan Thit th lng bc hi ln nht, t n 3,97 ( mm/ngy - m).Bng 1.3. Bc hi trung bnh ngy ti Phan Thit (mm/ ngy - m ).Sinh vin thc hin: Trn Nam Hi Lp: 47N18Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiThng 1 2 3 4 5 6 7 8 9 10 11 12Trung bnhTrmPhan Thit4,724,564,734,794,233,743,383,232,792,983,844,663,97Da vo ti liu bc hi ca trm Phan Thit, lng bc hi ln nht t vo thng 4 hng nm vi khong 4,79(mm/ngy - m). y l con s tng i ln, biu hin iu kin kh hu nng min ng Nam B nc ta, v y cng l vng c lng ma kh nh. Bc hi trung bnh thng nh nht xy ra vo thng 9, khong 2,79 (mm/ngy - m). iu cho ta thy s chnh lch bc hi gia cc thng trong nm l kh ln.c. Ma:Ch ma trn lu vc th hin r quy lut ca ch gi ma.Lng ma trung bnh nhiu nm ca lu vc khong 1500 (mm). Lng ma thay i theo a hnh tng vng trong lu vc. Khu vc nm v tr t ma, c lng ma bnh qun t 1000 (mm) 2000 (mm).Mi nm, ma cng phn b lm hai ma. Ma ma thng bt u t cui thng 4 n cui thng 10 v lng ma chim khong 85% 90% lng ma c nm. Cn ma kh thng ko di t thng 11 n thng 4 nm sau vi lng ma ch chim 10% 15% lng ma c nm.Bng 1.4. Lng ma trung bnh thng ca mt s trmxung quanh khu vc. ThangTrm1 2 3 4 5 6 7 8 9 10 11 12Sng Ly 0,1 0,0 17,5 18 116 163 126 148 168 198 58,6 3,7Phan Thit 0,9 0,4 5,0 29 139 148 175 175 195 181 50,5 12,8T Li 8,8 14,5 47,6 105 251 428 393 543 438 333 147 38,6i Nga 26,4 31,5 79,8 153 216 283 257 382 292 283 154 71T Pao 5,9 5,8 32,4 56,3 221 403 437 551 379 261 91 12d. Gi:Sinh vin thc hin: Trn Nam Hi Lp: 47N19Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiTheo ti liu v gi ti trm Phan Thit, lu vc sng Quao chu nh hng ca hai loi gi chnh:- Gi ng thng thi t thng 11 n thng 4, c ngun gc t Bc bn cu, c m rt thp, gy ra tnh trng kh hn. Trong nhng thng ny, nhit thp hn nhit trung bnh nm, cn s gi nng v bc hi li cao hn so vi trung bnh nm.- Gi Ty thng thi t thng 5 n thng 10, c hnh thnh t vnh Bng Gan, mang theo nhiu hi nc v gy ma nhiu. Trong cc thng ny, m v nhit cao hn so vi trung bnh nm nhng lng bc hi v s gi nmg th thp.Bng 1.5. Hng gi trung bnh, tc gi max v trung bnhti trm Phan Thit (m/s).Thng1 2 3 4 5 6 7 8 9 10 11 12Trung bnhHng N T T T T T T,Vmax15,315,015,014,713,012,713,310,812,511,014,813,718,5Vtbnh5,7 6,3 5,8 5,1 4,3 4,8 4,7 4,7 4,2 4,0 4,5 5,0 4,9Do gn bin nn khu ti c tc gi ln hn cc ni khc rt nhiu, bnh qun ti Phan Thit l 4,9 (m/s).e. m:Khu vc c nn nhit tng i cao nhng m li thp hn so vi vng xung quanh.Theo ti liu o ti trm Phan Thit:Bng 1.6. m max, min, trung bnh ti trm Phan Thit ( % ).Thng1 2 3 4 5 6 7 8 9 10 11 12Trung bnhHtb74,375,276,276,579,081,583,083,585,383,378,874,879,3Hmax93,094,096,094,097,097,098,097,098,097,098,098,096,4Hmin41,051,045,049,044,041,048,052,052,049,036,040,045,7S thay i m trong nm ph hp vi ch ma, nhng thng ma ma c m cao, nhng thng ma kh c m thp. m bnh qun ti trm Phan Thit l 79,3%.Sinh vin thc hin: Trn Nam Hi Lp: 47N110Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hif. Bc x mt tri:Bng 1.7. S gi nng trung bnh ngy ti Phan Thit (gi/ngy ).Thng1 2 3 4 5 6 7 8 9 10 11 12Trung bnhS gi nng9,419,379,829,858,087,197,286,666,526,667,348,788,08Nm trong vng kh hn vo bc nht nc ta nn so vi cc khu vc xung quanh, khu ti c s gi nng nhiu hn, trung bnh l 8,08 ( gi/ngy ), s gi nng bnh qun nm l 2910 (gi/nm).V ma kh, s gi nng cao, trung bnh 9,45 (gi/ngy), ma ma s gi nng t hn, khong 7,10 (gi/ngy).1.1.2.2. Tnh hnh thu vn1. Mng li sng sui trong khu vcNgun nc ch yu trong khu vc l nc mt bao gm mng li cc sng sui ln nh trong khu vc nh: Sng Ci, sui Trm, sng Thang, sng Trao....Song c im ca khu vc l a hnh dc, kh hu kh nng, ma t, nng nhiu nn cc sng sui phn ln kh hn, ht ma l ht nc. Duy ch c sng Ci l sng ln nht trong khu vc l c nc quanh nm.Sng Quao l nhnh ln nht ca h thng sng Ci, c lu vc hng nc kh ln, c nc quanh nm, lu lng trung bnh ma kit t 0,1 (m3/s) 0,3 (m3/s), c kh nng gi v iu tit nc, p ng mt phn yu cu dng nc trong khu vc.Ngoi ra, trong khu vc ln cn cn c mt s sng sui c lng nc kh di do nh: sng Ly, sng La Ng....2. Mng li trm o thu vn trong khu vcTrn sng Quao khng c trm thu vn o c dng chy nn s phn tch ch dng chy n sng Quao gp kh khn. Trn lu vc dng chy n h sng Quao c mt s trm trn sng La Ng th hin c tnh cht dng chy trong vng, l cc trm sau:- Trm Ph Din, c din tch lu vc 3060 (km2).- Trm T Pao, c din tch lu vc 2000 (km2).- Trm i Nga, c din tch lu vc 373 (km2).- Trm sng Ly, c din tch lu vc 964 (km2).3. Cc c trng dng chySinh vin thc hin: Trn Nam Hi Lp: 47N111Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hia. Ch dng chy sng ngiCh yu ph thuc vo ch ma v iu kin mt m. Cng nh cc vng khc nc ta, lu vc sng Quao c hai ma l v kit. Tuy nhin, do lng ma trong nm ca lu vc tng i nh nn dng chy cng rt b so vi vng khc, k c lu vc sng Ly v sng La Ng l nhng khu vc ln cn nht. Do vy b sung cho ngun nc sng Quao ngi ta dng ngun nc t sng an Sch, mt nhnh ca sng La Ng.Do sng Quao l sng c lp chy thng ra bin nn ch nc sng chu nh hng ca thy triu vi ch nht triu khng u.b. Dng chy nmSng Quao nm trong khu vc t ma, nhng thng ngun, c bit l lu vc sng an Sch, sng La Ng li c lng ma kh ln nn lng dng chy c th b sung cho lu vc hng nm tng ln.GnkhuvcthnhphPhanThit, muyndngchynmch t 10 (l/s/km2), nhng ngc ln vng ni ti lu vc tp trung nc cho sng Quao m un dng chy t 20 ( l/s/km2) 25 ( l/s/km2), thm ch c vng t n 35 (l/s/km2) 40 ( l/s/km2).Bng 1.8. Lu lng bnh qun thngv bnh qun nm ca nhiu nm cc trm (m3/s). ThngTrm1 2 3 4 5 6 7 8 9 10 11 12NmT Li79,0747,739,847,377,8249 421 707 829 717 355157311i Nga 3,85 2,5 2,3 3,3 6,917,725 4139,135,717,47,6 16,8T Pao 20,612,49,611,423,464 103 188 173 165 82 41 75Ph Din26 16 14 15 30 107 203 290 360 274 119 44 125Sng Ly2,2 1,1 0,9 1,2 5,9 8,311,512,429 56 17 4,5 12,6c. Dng chy lLu vc sng Quao thng xy ra l ln nht vo thng 10. Nguyn nhn gy l ln nht hng nm lu vc hu ht do hi t nhit i sinh ra. V a th dc, ma li bin i rt ln theo thi gian nn l xy ra thng l l n v ln xung nhanh.4. Cc c trng ca lu vc Sinh vin thc hin: Trn Nam Hi Lp: 47N112Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiNgun nc cho khu vc ch yu l ngun nc tp trung t lu vc sng Quao, v c b sung t lu vc sng an Sch, mt nhnh ca sng La Ng.Lu vc sng Quao v sng an Sch c mt s c im sau:a. Din tch lu vcPhn lu vc sng an Sch c din tch 120 (km2), n l mt nhnh ca sng La Ng, nm gn trong khu vc rng ni him tr, i li rt kh khn, giao thng khng thun tin.Phn lu vc sng Quao c th chia lm hai phn, phn i qua vng i ni c din tch 296 (km2), phn cn li i qua vng ng bng, c din tch khong 400 (km2).b. Thm phKt qu kim k hin trng rng nm 1993 cho thy t lm nghip 94.511 (ha) chim 73,7% tng qu t ca huyn, trong t c rng t nhin: 68.695 (ha) vi din tch che ph kh cao 72,7%, tng tr lng g cc loi 4,4 (triu m3). n nm 2000, thng k t ai xc nh li t lm nghip: 62.186,6 ha, t din tch che ph 48,5% trong t c rng t nhin 58.596 (ha), t rng trng 3.590,6 (ha), ch yu l rng phng h 3.563,1 (ha) v rng sn xut 27,5 (ha). Tuy nhin xt v mt cht lng th trng thi rng giu v trung bnh chim 20,5% din tch 14.116 (ha) v t 33,4% tr lng g 1.471.000 (m3) tonhuyn . Tuy nhin loi rng ny phn b trn a hnh cao, dc ln m chc nng phng h u ngun phi t ln hng u. Din tch rng ngho v rng non phc hi chim n 79,3% din tch rng 54.020 (ha) v 66,5% tr lng g 2.929 (m3). Nhng loi rng ny phi n 20 -30 nm sau mi c th khai thc c. V vy phng hng pht trin lm nghip ca huyn Hm Thun Bc trong nhng nm ti ch yu l bo v vn rng hin c p ng nhu cu phng h v pht trin vn rng qua vic trng mi rng.c. dcPhn lu vc sng Quao thuc vng i ni c dc lng sng kh ln. Hai bn c nhiu nhnh vo sng Quao. Do c im hai bn h l cc dy ni cao nn cc nhnh vo len li qua cc thung lng, cc dy ni, v th rt quanh co v c dc kh ln.K t sau ni Bi , a hnh lng sng hon ton khc hn vi c im pha thng ngun, dng sng bt u chy qua khu vc ng bng, dc lng sng c gim nh i qua cc vng trng trt, n cu Ph Long, dc lng sng rt b. T y dng chy trong sng chi nh hng rt ln ca thu triu.Ti im cu Ph Long, tuy ch dng chy trong sng mang nng tnh cht vng triu nhng mn cn rt nh. iu c th gii thch l do dc lng sng c s thay i t ngt ti im nt cu Ph Long.Sinh vin thc hin: Trn Nam Hi Lp: 47N113Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi5. Cht lng nc a. Nc mtH thng sng ngi ca huyn Hm Thun Bc thuc h thng sng Ci Phan Thit, bt ngun t cao nguyn Di Linh. Do a hnh dc nn a s sng ngi ca huyn ngn, dc v hp thng chy xit vo ma ma v kh cn vo ma kh. Vi tng chiu di sng ngi ca huyn l 433,42 (km), tng lu lng trung bnh t 289 (triu m3/nm) v din tch lu vc 1.050 (km2) gip cho ti tiu hng chc ngn ha gieo trng la nc cahuyn .b. Nc ngm Tim nng nc ngm ca huyn khng ln nhng vn c th p ng nhu cu nc sinh hot cho nhn dn mt s khu vc. Bao gm:- Cc tng nc di ct l vng c kh nng v trin vng ln nht trn a bn huyn. su t 50 100 (m) c th t 1 2 (m3/gi) n 3 4 (m3/gi) tng ng vi 50 150 (m3/ging/ngy).- Cc tng cha nc cc thung lng sng v tam gic ca sng c giu nc t loi kh sau vng ct , song c s thay i ty thuc vo thnh phn thch hc.Trin vng khai thcmigingc tht2 30 (m3/gi),cht lngnc khng cao, lng khong cht trong nc thp, ni gn ca sng b nhim mn, lng khong cht tng t 1,5 4,5 (g/lt).- Cc tng cha nc trm tch: Phn b ch yu vng g i, c cu to ch yu l Macma xm nhp, mc nt n ca t nn kh nng cha nc km. Trin vng khai thc ca ging thng nh hn 0,5 (m3/gi), nhng cc v tr gn t gy c th khai thc t 12 (m3/gi).1.1.3. Tnh hnh a cht th nhng ca khu vc 1.1.3.1. Tnh hnh a cht Vng i ni c a cht kh cng chc v n nh, c hai tng a cht chnh l:- Tng ph t, bao gm t st ln dm sn (lp 4c).- Tng gc granit phong ho nh, kh cng chc, t nt n, t thm nc.Ngoi ra cn c mt s a tng khc nh: tng bi tch ct, cui, si (2b v 2d)Khu ti l vng ng bng, c a cht kh phc tp, c th gp cc tng a cht sau:- Lp ct, cui si lng sng, sui (lp1). Ct thch anh ht th, nh, chim 50 % 60 %. Si kch thc 1 2 (cm) chim 20 % 30 %. Cui kch thc 2 10 (cm) chim 10 % 30 %, ngun gc bi tch, chiu dy cha xc nh.- Lp 2a: L lp t ct nh n ct ht trung chiu dy trung bnh l 2 (m).- Lp 2b: L t st nh n st nng.- Lp 2d: Ct ln si n ct ht mn.Sinh vin thc hin: Trn Nam Hi Lp: 47N114Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Lp 41: t ct n ct, trng thi ri rc, kt cu km cht, d st l khi gp nc, chiu dy trung bnh 0,5 0,7 (m). - Lp 42: st nh n st nng, trong t c ln mnh dm granit phong ho mnh, kch thc 3 5 (cm), d sp l khi gp nc, chiu dy trung bnh 0,7 (m).1.1.3.2. Tnh hnh th nhng 1. Cc nhm t chnh a. Nhm t ph sa Din tch 17.940,5 (ha) chim 13,95 % din tch t nhin, ch yu l loi ph sa c bi, ph sa khng c bi, ph sa loang l v ph sa ngi sui. Nhm t ny phn b trn a hnh bng, sa cu nh trung bnh, ph kh cn i. Thch hp vi la, hoa mu v cy n qu....Hin trng s dng t l mt trong ba vng trng im la.b. Nhm t xmDin tch 32.588,02 (ha) chim 25,41 % din tch t nhin ch yu l loi t xm trn ph sa c, xm trn Granit v sa thch, phn b ch yu cc vng i g ln sng, t nh, ngho dinh dng. Kh nng pht trin trng rng, cy cng nghip ngn ngy nh: Bng, ma; cy cng nghip di ngy nh: iu, cc cy thc phm v pht trin ng c chn nui gia sc.c. Nhm t vngDin tch 58.853,26 (ha) chim 45,89 % din tch t nhin, phn b ch yu a hnh i ni vi cc loi t: Nu tm trn bazan, nu trn dacide, l cc loi t mu m, tng t dy, ring loi t vng trn macma acid (granit), vng trn Rhoylite c tng mng, ngho dinh dng. Qua nhng c im trn cho thy t vng c t l din tch s dng nng nghip thp v phm vi thch hp cho cy trng hp. t t dc ch yu ph hp vi mt s loi cy cng nghip ngn ngy v di ngy, hoc cc cy trng can hng nm.d. Nhm t ct bin Din tch 13.241 (ha) chim 10,33 % din tch t nhin. Gm cc loi: t ct ,cttrngv ctvng,nghodinhdng,dc t3 150,d trira vdi ng.Trong cc loi t trn th t ct l t c tng dy. Tim nng pht trin nng nghip ca loi t ny khng c, ch yu l trng rng chn ct v bo v mi trng.e. Nhm t dc t Din tch 1.603 (ha), chim 1,25 % din tch t nhin, phn b ri rc ven cc hp thu v thung lng. t dc t c hnh thnh t sn phm ca cc vng ni cao ln cn tch t xung cc khu vc c a hnh thp hn v c th c pha ln vi cc sn phm t cc vng xa hn do sng sui mang n. V vy cc vng dc t thng Sinh vin thc hin: Trn Nam Hi Lp: 47N115Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hic s phn bit r rng thnh phn cu trc v sa cu. Nhn chung t dc t c thnh phn c gii nh n trung bnh, tng t dy. Do c im phn b nn t dc t thch hp cho b tr trng la nc v cy hng nm, khu vc c mc nc ngm su cng ph hp vi cc cy lu nm v cy n qu.f. Cc nhm t khcDin tch 4021,42 (ha), chim 3,14 % din tch t nhin, gm cc loi t xi mn tr si , t mu vng trn granit, t hp t vng i ni, sng h....hu ht c dc 25 %, tng t mng, ph nhiu thp. Ch yu trng rng bo h v pht trin vn rng.Nhn chung ti nguyn t ca huyn Hm Thun Bc kh a dng v c phn b trn nhiu a hnh khc nhau, c tim nng pht trin nng - lm nghip, c kt cu nn mng a cht cng v n nh, do khi xy dng cc cng trnh khng i hi chi ph cao.1.2. Tnh hnh kinh t c hi ca khu vc 1.2.1. Phn khu hnh chnh v dn c 1.2.1.1. Phn khu hnh chnh Tnh Bnh Thun c 1 thnh ph l Phan Thit, c 8 huyn l: Tuy Phong, Bc Bnh, Hm Thun Bc, Hm Thun Nam, Hm Tn,Tnh Linh, c Linh v huyn o Ph Qu.Hm Thun Bc l mt huyn min nipha bc ca tnh Bnh Thun. Huyn c 15 x v 2 th trn l Ma Lm v Ph Long. Trong c 5 x, th trn ng bng, 8 x min ni,4 x vng cao.C 7 x nm trong khu ti sng Quao l: Hm Tr, Hm Ph, Hm Lm, Hm Chnh, Ma Lm, Hm Thng v Hm c.1.2.1.2. Dn c -Dns: Theosliuiutradns1/4/1999: TngdnshuynHm Thun Bc l 149.654 ngi chim 14,03 % dn s ton tnh, vi 49,69 % l nam, 50,31%ln, trongdnssngth trnl13.597ngi chim8,49%v 136.057 ngi sng nng thn, chim 91,06 %.- Mt dn s bnh qun: 118 ngi/km2, cao nht l: 968 (ngi/km2) (x Hm Thng), thp nht l: 8 ngi/km2 (x ng Tin).- T l tng dn s t nhin: 1,85 %.-Tonhuync4cngngdntcgm: Ngi Kinhc140.085ngi (chim 92,76 % dn s ton huyn), cc dn tc khc (ngi Chm, ngi K`ho v ngi Graylay) c 10.934 ngi (chim 7,24 % dn s ton huyn). Ngi Kinh phn b hu ht cc x, th trn cu huyn. Song a s sng cc vng trung tm dc theo Sinh vin thc hin: Trn Nam Hi Lp: 47N116Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hiquc l, ven trc giao thng, c u t c s han tng, c n np tip cn th trng, nng ng v c nhiu kinh nghim trong sn xut lm n. Ngi Chm sng ri rc cc x Hm Tr, Hm Ph V th trn Ma Lm, cn ngi K`ho v ngi Graylay sng ch yu cc x vng cao Thun Minh, ng Tin, ng Giang v La D.- Vi c im dn c phn b theo trc l, quc l l mt u im trong qu trnh hnh thnh cc khu dn c tp trung ven quc l, nhng li c nhiu hn ch v din tch s dng thng nm trong hnh lang bo v ng b, ng in. Do , vic m rng mt bng pht trin cc khu vc trung tm v cc cm dn c hai bn tuyn ng theo chiu su l iu cn c ch trong tng lai.- V ngun nhn lc:+ Tng s lao ng ca huyn l 71.834 ngi, chim 48 % dn s, cht lng ngun lao ng khng u.+ c im c bn ca ngun lao ng: Ch yu l lao ng ph thng, trnh thp, cha qua o to,lao ng c tay ngh chim mt t l thp. Trong thi gian ti cng tc o to tay ngh cn ht sc ch thch nghi vi c ch th trng trong thi k cng nghip ho hin i ho p ng yu cu pht trin kinh t - x hi ca huyn.+ Lc lng cn b khoa hc k thut ca huyn rt t, ton huyn nm 2000 c 2.645 ngi tt nghip trung hc chuyn nghip, cao ng hoc i hc. Bnh qun trn 1000 ngi dn c 18 ngi c trnh trung hc tr ln.- Ngh sng chnh l lao ng nng nghip 54.594 ngi chim 76 %, cn li l lao ng phi nng nghip.- V i sng kinh t: Ngh sng chnh l nng nghipj nhng sn xut li bp bnh do thiu nc nn i sng nhn dn rt kh khn, ch sn xut nng nghip c vo ma ma, cn ma kh i cht ci, t than kim sng.- V i sng vn ha: Mng li c s vn ha ca huyn cn chp v, ngho nn. Ton huyn c 1 nh truyn thng, cha c trung tm vn ho th thao ca huyn l, cha hnh thnh nhng t im vn ho thu ht thanh thiu nin n sinh hot. Nhn chung, mc hng th vn ho ca nhn dn cn thp c c s chnh lch ln gia cc vng ng bng, min ni v vng cao.- V y t v gio dc: Cn nhiu bc xc. Hot ng gio dc cha p ng c yu cu pht trin x hi, c s vt cht trng hc xung cp, thiu gio vin v trang thit b hc tp. Chnh sch o to v thu ht cn b k thut cn nhiu bt cp. Trang thit b v c s y t cn nhiu yu km, thiu bc s chuyn khoa gii p ng yu cu cha bnh ti ch cho nhn dn.1.2.2. Hin trng kinh t 1.2.2.1. Kinh t nng nghip 1. Trng trt Sinh vin thc hin: Trn Nam Hi Lp: 47N117Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hia. Phn b t aiTheo ti liu kho st ca huyn Hm Thun Bc (Thng 7/1983) v ca s nng nghip Thun Hi (Thng 11/1983) th t ai trong khu vc hng li nh sau:Bng 1.9. Phn b din tch t ai vnghng li nm 1983 (ha).Tn xDT tnng nghiptcanh tcCylu nmTng cngt trng la t mu,cy CNCng3 v2 v 1 vHm Thng1257 1252 1224 64 825 335 28 5Hm Lim 1439 1437 12741274163 2Hm Chnh 1684 1659 1407 731334252 25Hm Ph 1559 1557 1345 62 2781005212 2Hm c 1389 1358 1169 86 532 551 159 31Ma Lm 888 848 734 50 358 316 114 40Tng 8216 8111 7153 26220764816958 105Loi t Din tch ( ha )Tng din tch t t nhin (Tnh n cao + 40)16.263- t nng nghip8.216- t canh tc 8.111- Din tch trng la xen mu 7.513- Din tch chuyn mu 958- t c kh nng khai hoang 468b. C cu v nng sut cy trng Vic b tr h thng cy trng ch yu da vo iu kin t nhin ca vng, vng thp c nc trng la, vng cao thiu nc trng mu v cy cng nghip. Do khng ch ng c ngun nc ti nn nhn chung nng sut cy trng thp v khng n nh, i sng nhn dn gp nhiu kh khn.Nng sut cc loi cy trng:Sinh vin thc hin: Trn Nam Hi Lp: 47N118Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- La chim : 2,72 (T/ha).- La ma: 1,22 (T/ha).- Cy mu: 1,75 (T/ha).- Cy cng nghip : 3,41 (T/ha).2. Chn nui Chn nui l mt th mnh ca tnh. Bnh Thun c coi l vng chn nui tru, b sa, d, gia cm,....Hin nay Bnh Thun c n tru gn 8.000 con, n b trn 120.000 con, n d khong 13.000 con, heo trn 200.000 con, gia cm hn 3 triu con. Bnh Thun ang c k hoch ku gi vn u t vo chn nui b tht - sa vi quy m t 500.000 700.000 con ti Hm Thun Bc, Bc Bnh, nui heo tht v ch bin tht ti Hm Thun Bc, c Linh vi s lng 30.000 50.000 con.3. Lm nghip Lm nghip l ngun thu nhp ln ca khu vc sau nng nghip. Din tch rng ca huyn khong 62,185 (ha) chim 17 % din tch rng ca tnh.Tuy nhin din tch v tr lng rng ang gim st mt cch ng k, din tch rng trng tuy c tng nhng vn khng b c din tch rng b khai thc.4. Kinh t vn Theo s liu ca phng nng nghip Hm Thun Bc:- Din tch trng thanh long : 1000 (ha).- Nng sut : 20 (tn/ha).- Tng sn lng hng nm : 20.000 (tn/nm).Hiu ch trng thanh long c tnh khong 49 (t ng/nm).Ngoi ra cn c cc loi cy n qu khc nh: Nhn, nho, xoi, chm chm....Hin nay, Hm Thun Bc cn c mt s d n pht trin kinh t vn ang gi vn u t nh: Trng cy cnh Hm Hip, a Mi, trng rau sch a Mi, Hm Hip, Hm Nhn....1.2.2.2. Vn nc sinh hot v v sinh nng thn 1.Nc sinh hot Tnh n cui nm 2000, ton huyn c 6.379 ging o, 944 ging khoan, 786 b nc ma v 10000 lu cha nc 2 m3, nh vy gii quyt nc sinh hot cho 18255 h chim 62,3 % dn s ton huyn.2.V sinh mi trng n cui nm 2000, ton huyn c 15.774 h x hp v sinh, trong c 4.862 h x t hoi chim t l 30,8 %. T l h s dng h x hp v sinh t 53,9 %. Bn cnh , h thng thot nc ti cc khu dn c cha c xy dng nn nc thi cng gy tc ng xu n mi trng. Vn x l rc, nc thi cn nhiu bt cp, bi cha rc cha c quy hoch.Sinh vin thc hin: Trn Nam Hi Lp: 47N119Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi1.2.2.3. Kinh t cng nghip v cc ngnh kinh t khc 1. Cng nghip v tiu th cng nghip Hm Thun Bc c ngun ti nguyn khong sn kh phong ph :- xy dng c tr lng ln, ch yu l granit, riote tp trung ti cc m nh T Zn, Hm c, ni ch - Hng Lim, ni X Th - Hm Tr.- p lt c cc ni Gi - Thun Ho vi tr lng ln, l thnh khi tng trn din rng, t yu cu cht lng cho ngnh xy dng.- Ct thu tinh tr lng khong hn 20 triu tn, cht lng ca, ch yu tp trung Hng Lim.Hin nay, mt s m ang khai thc rt c hiu qu. Sp ti, huyn khuyn khch cc nh u t kho st v u t pht trin cc lnh vc khai thc v sn xut vt liu xy dng.Trn lnh vc tiu th cng nghip, Hm Thun Bc v ang thc hin vic khi phc cc lng ngh truyn thng v xy dng cc cm tiu th cng nghip mi nh: my tre an, th cm....2. Thu sn Dc b bin c cc ng cng nh Con Ch, Phan Thit, Mi N....l iu kin thun li pht trin ngnh thu sn.c xc nh l mt ngnh kinh t quan trng ca tnh v Hm Thun Bc ni ring, c s h tng ngh c c ch u t xy dng, cng chnh sch khuyn khch v thu, h tr vn tn dng u t nh bt xa b l ng lc thc y ngnh thu sn pht trin trong thi gian qua.S lng tu thuyn nh bt v cng sut tng nhanh. Nm 2000, ton tnh c 5.097 thuyn nh bt xa b, nng xut sn lng hi sn nh bt t 75.739 tn nm1992ln 128.700nm 2000.Nui trng thu sn, nht l tm tip tc pht trin v cng ang thu ht vn u t.Cng tc bo v ngun li hi sn c quan tm, thng xuyn tuyn truyn, ph bin cho cc ng dn cc quy nh v kch c, chng loi v ma v khai thc. Do , hn ch c ti a s vi phm cc quy nh bo v ngun li hi sn.3. C s h tng Huyn u t xy dng nhiu cng trnh quan trng phc v dn sinh kinh t.V mng li giao thng vn ti, trn a bn huyn hin c 3 trc l quan trng l QL1A, QL28 v tuyn ng st Bc Nam. Ngoi ra cn c: 65,2 (km) tnh l, 54,5 (km) huyn l v ng lin huyn, 55 (km) ng lin x, 59,7 (km) ng ni ng ca vng nguyn liu ma v 328,6 (km) giao thng ni ng. Mng li Sinh vin thc hin: Trn Nam Hi Lp: 47N120Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Higiao thng ca Hm Thun Bc c ch nng cp, m rng, to thun li cho vic giao lu, pht trin kinh t - x hi a phng.ng thu trong khu vc ch c sng Quao l sng c nc quanh nm. Cc con sng khc nh v c dc ln, lm ghnh thc, li t ma, ma kit thng khng c nc, lm cho giao thng thu ca huyn khng pht trin.Mng li in quc gia ko n trung tm cc x v cc khu dn c, 80 % s h c s dng in.Mng li thng tin lin lc tng bc c hin i ho, nng cao cht lng hot ng, 17/17 x v th trn c in thoi lin lc.4. Thng mi - dch v Hot ng thng mi - dch v cn bc l nhiu hn ch nh: Hot ng nh l, t chuc lan trn, phn tn, thiu nng lc kinh doanh nn hiu qu khng cao, c hin tng p gi, bun bn hng gi, cha to c th trng lu thng hng ho n nh, cc trung tm thng mi - dch v v h thng ch cc x, th trn quy m cn nh, a s ch hot ng theo bui sng hoc bi chiu, cng tc qun l ch cha c quan tm, c ni bung lng.1.2.3. Yucupht trinkinhttrcmt vludi i vi ngnhnnglm nghip 1. Tng v v tng nng sut cy trng a. Yu cu tng vChuyn t trng la 1 v bp bnh sang canh tc n nh vi 3 v:- V chim: trng la.- V ma: trng mu.- V ng: trng ng hoc loi cy thc phm thch hp vi th nhng tng vng.b. Yu cu tng nng sut - i vi la, nng sut tng ln t nht l 4 (T/ha). - i vi ng, nng sut tng ln 2 (T/ha).2. Pht trin nng nghip theo hng hng ho a. Theo quy hoch tng th ca tnh, phng hng, nhim v v mc tiu pht trin n nm 2020y mnh cng nghip ho, hin i ho nng nghip v nng thn. Pht trin ton din nng nghip theo hng sn xut hng ho gn vi cng nghip ch bin, tng dn t trng ca cy cng nghip, cy n qu, chn nui. Hnh thnh cc vng sn xut nng sn hng ho tham gia xut khu, hnh thnh cc vng nguyn liu cho cng nghip ch bin....i vi din tch t nng nghip khai thc, cn p dng cc tin Sinh vin thc hin: Trn Nam Hi Lp: 47N121Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hib khoa hc k thut vcng ngh tng nhanh nng sut. i vi phn din tch t nng nghip cha khai thc c, cn u t vn khai thc ht tim nng.b. Hng pht trin mt s cy trng chnh- Cy la: Gi vai tr quan trng trong vic gii quyt lng thc cho huyn v tng bc nng cao cht lng hng ti xut khu. Vng chuyn canh la ca huyn s b tr cc x: Hm Chnh, Ma Lm, Hm Thng, Hm Nhn, Hm c, Hm Lim, Hm Ph, Hm Tr. Mc tiu n nm 2020 l hnh thnh vng trng la cht lng cao xut khu vi din tch khong 4000 ( ha ).- Cy ng: L cy lng thc c kh nng pht trin cc x min ni, vng cao nh: ng Giang, La D, Thun Ha. Nng dn din tch bp lai t tc lng thc ti ch, tin ti tr thnh sn phm hng ho. n nm 2020 t din tch 2000 ha, sn lng 6000 (tn).- Cy thc phm: B tr din tch rau xanh p ng nhu cu trong huyn v thnh ph Phan Thit. i vi cy u cc loi, cn s dng ging mi, b tr thi v v lun canh thch hp t nng sut cao v n nh.- Cycng nghipngnngy: nhbng,ma,m....b trchyu cc x Thun Ho, Hng Sn, Hng Lim nhm tn dng ngun nc c cung cp t h Sui .- Cy cng nghip di ngy v cy n qu: Cy cng nghip di ngy c tc dng ph xanh t trng tt, nn b tr cc x vng cao nh: ng Giang, La D,....- Cy n qu nh thanh long, nhn, nho....pht trin theo m hnh kinh t gia nh, kinh t vn.3. Pht trin dch v v cc ngnh kinh t khc a. Dch vCn khuyn khch v y mnh pht trin cc loi hnh thng mi - dch v phc v sn xut v i sng, xy dng cc cm dch v u mi v h thng ch nng thn hnh thnh th trng thng sut nhm y nhanh qu trnh chuyn dch c cu kinh t nng nghip v nng thn.b. Cng nghip - tiu th cng nghipCh yu pht trin cng nghip ch bin nng lm sn thc phm, khai thc vt liu xy dng v ngnh ngh truyn thng.c. C s h tngCn huy ng mi ngun lc :- Pht trin v nng cp h thng giao thng t quc l n tnh, huyn l v ng lin x.Sinh vin thc hin: Trn Nam Hi Lp: 47N122Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Hin i ha mng li bu in ton huyn, hon thin mng li thng tin lin lc, n nm 2020 c 4 5 my in thoi/100 dn.- C bn hon thnh in kh ho nng thn vo nm 2020, t mc tiu 95 % h gia nh c in thp sng.d. Nc sch nng thnThng qua chng trnh cp nc sch nng thn, cc chng trnh ti tr ca UNICEF v huy ng nhn dn xy dng ging o, ging lp bm tay, cc b cha v lc nc sch.... cc cm dn c tp trung, phn u n nm 2020 t t l 100% dn s c dng nc sch.e. Khoa hc cng ngh v mi trngn nm 2020 hng tp trung ch yu vo cc lnh vc:- ng dng cng ngh sinh hc ci to ging v phng tr dch bnh tng hp cho cy trng vt nui.- C gii ho khu canh tc v thu hoch.- Hnh thnh cc cm dn c mi, gii quyt nc sch, v sinh mi trng, xy dng nng thn mi.- Pht trin rng ri cng ngh thng tin v tin hc.- V sinh mi trng: Khai thc hp l cc ti nguyn thin nhin, trng v bo v rng. Thc hin nghim tc nh gi tc ng mi trng i vi cc c s sn xut kinh doanh, kp thi x l cc vi phm, c gii php c bn x l nc thi nhim bnh vin v trm y t.1.3. Hin trng thu li ca khu vc1.3.1. Hin trng phn vng ti ca khu vc Huyn Hm Thun Bc c th b tr thnh 4 vng ti chnh:1. Vng ng bng nm bn tri sng Quao C a hnh kh bng phng, cao t 25 (m) xung n 5 (m). Gm cc x: Hm Nhn, Hm c, Hm Thng v th trn Ma Lm, c phng hng pht trin cc loi cy trng ch yu l: bp lai, thanh long, rau cc loi...Ngun nc ch yu cung cp cho vng ny l sng Quao v h Sui .2. Vng ng bng nm bn phi sng Quao C cao t 50 (m) xung n 25 (m), gm cc x: Hm Tr, Hm Ph, Thun Minh, Hm Chnh, Hm Lim, Hm Hip. y ch yu trng la, ng v mt s cy n qu.y l vng c tim nng t ai ln pht trin sn xut nng nghip. Tuy nhin, hin nay ngun nc tp trung ch yu cp cho vng l nc sng Quao. V vy, ma kit, khi lng nc sng Quao rt nh, ch t 0,1 (m3/s) 0,3 (m3/s) th vng ny gn nh b thiu nc hon ton, khng sn xut c g.Sinh vin thc hin: Trn Nam Hi Lp: 47N123Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi3. Vng pha bc huyn C a hnh mt phn l i ni thp, mt phn l ng bng. Gm cc x Hng Lim, Thun Ho v Hng Sn. Ch yu trng cc loi cy cng nghip nh bng, ma, iu, cy n qu.Ngun nc ch yu cp cho vng ny l h Sui .4. Vng cao C a hnh ch yu l i ni kh cao, gm cc x : a Mi, ng Giang, ng Tin v La D, ch yu trng cy n qu, iu, cao su....Ngun nc cung cp cho vng ny c ly t h cha La Ng.1.3.2. Hin trng h thng ti trong khu vc 1.3.2.1. Cng trnh u miCng trnh u mi trong khu vc hin c h thng cc p dng nh: Cy Kh, Xuyn, Kim Long vi kh nng ti kh ln. Tuy nhin, hu ht cc cng trnh u mi u khng c cng ly nc, cc p ch lm nhim v dng nc.a. H thng p cy khL p dng bng b tng, c cc kch thc c bn:- Chiu cao p: H = 3,5 ( m ).- Chiu di p: B = 28 ( m ).- Mi thng lu: m = 0.- Mi h lu l lp t p trn phn b tng v c gia c bng lt chng xi, dc mi khong 1,5.- Thn p c b tr 1 cng h chia nc v p Kim Long h lu.b. p Kim LongL p r thp, kch thc c bn nh sau:- Chiu cao p: H = 5 ( m ).- Chiu di p: B = 40 ( m ).- Chiu rng trn: b = 25 ( m ).- Mi thng lu: mt = 0.- Mi h lu: mh = 1,5.c. p Xuyn L p b tng, c cc kch thc c bn:- Chiu cao p: H = 3,5 (m).- Chiu rng trn: b = 20 (m).- Mi thng lu: m = 0.- Mi h lu: m = 1.Sinh vin thc hin: Trn Nam Hi Lp: 47N124Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Chiu di tiu nng: L = 15 (m).2. H thng knh mng dn nc - Knh chnh ca p Cy Kh di 9 (km), b rng knh knh u mi bnh qun 15 20 (m).- Knh chnh ca p Kim Long di 14 (km), rng 10 (m).- Knh chnh ca p Xuyn di 13 (km), rng 20 (m).3. nh gi v mc h hng v xung cp ca cng trnh v knh mng V cng trnh u mi: Cc cng trnh ny c xy dng t rt lu. p Cy Kh v Kim Long xy dng t trong khng chin chng Php, cn p Xuyn xy dng trong khng chin chng M. y l nhng cng trnh tm, sau c tu b dn, khng c n thit k, khng c ca ly nc u knh iu tit v chng l. Do , ma ma, nc sng theo cc ng dn nc ti vo, trn ngp ng rung, mang theo c ct si gy xi l, bc mu v ngp ng, nht l vng thng h lu p Xuyn, quanh ng st Thng Nht, lm nh hng ti nng sut ca cy trng.Hin nay, cc p ny khng cn m bo phc v sn xut nng nghip. Mt khc, do tnh cht tm thi ca cng trnh nn sau mi ma l, phn h lu ca cc p b xi l mnh. Ring vi p Kim Long, do hnh thc p v quy cch cha t yu cu v kch thc, trng lng nn mt p thng b l cun tri. V vy, hng nm sau ma l tt c u phi u t mt s vn kh ln cng c v a cng trnh vo phc v sn xut nng nghip.4. nh gi kh nng ti nc ca khu vc - Din tch c bo m ti chc chn: Trong 4 vng trn, vng cao do ly nc ti t h cha La Ng c lng nc kh di do nn c th xem nh c m bo ti chc chn.- Din tch bn hn: Vng pha bc huyn v vng ng bng nm bn tri sng Quao c cp nc t h Sui , do h Sui c dung tch nh, nn khng th p ng ton b yu cu nc cho cc vng ny, c th coi cc vng ny b bn hn.- Din tch b hn hng nm: Vng ng bng nm bn phi sng Quao, c ngun nc cung cp chnh l sng Quao, nhng do a hnh cao hn mc nc trong sng, cc p dng hin c li khng pht huy c tc dng, hn na, lng ma trong khu vc rt nh, nc ngm khan him nn vng ny gn nh b hn hon ton.1.3.3. Kt lun v yu cu thu li i vi khu vc Khu vc P1 tuy rng nhng l vng t kh cn, mang nhiu c th ca mt vng t cc Nam Trung B. a hnh nhiu i ni, dc ln, t si pha ct nhiu, ao h nh v sng sui ngn to nn s khc nghit cho ton vng.Sinh vin thc hin: Trn Nam Hi Lp: 47N125Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiTrong vng c gn 80 % dn s sng bng ngh nng nghip nhng vic sn xut nng nghip li hon ton l thuc vo thin nhin, sn xut bp bnh, khng n nh, i sng ngi dn rt vt v.Cn c vo tnh hnh chung khu vc c th ni rng nn kinh t trong khu vc c nhiu tim nng nhng gp nhiu kh khn nn cha c khai thc. Do , gii quyt vn v thu li l yu cu cp bch, c ngha to ln i vi s pht trin kinh t ca Bnh Thun ni chung v huyn Hm Thun Bc ni ring.T yu cu , xc nh nhim v cu cng tc nghin cu kh thi d n ti cho khu vc nh sau:- Tnh ton cc ch tiu k thut phc v cho lp d n u t.- xut phng n v tnh ton phng n.- Thit k cng trnh u mi.- Tnh ton kinh t ca d n.PHN II.TNH TON CC CH TIU K THUT PHC V CHO LP D N U TChng 2. Tnh ton cc c trng kh tng thu vn2.1. Mc ch, ngha v ni dung tnh ton 2.1.1. Mc ch, ngha 2.1.1.1. Mc ch Xc nh cc c trng thu vn thit k chnh l xc nh cc c trng thu vn ng vi tn sut thit k.2.1.1.2. ngha - V mt k thut: Cc c trng kh tng thu vn thit k s l c s xc nh ch ti ph hp vi yu cu nc ca cy trng ng thi tit kim c lng nc ti, m bo cy trng sinh trng v pht trin tt nht.- V mt kinh t: Tnh ton cc yu t kh tng thu vn gip ta xc nh hnh thc, quy m, kch thc cng trnh, ng thi cn gip cho cng tc quy hoch, thit k, cng nh vn hnh cc cng trnh mt cch ch ng v chnh xc. Tnh ton ng th cng trnh s pht huy ti a tc dng, hiu qu sn xut cao.Sinh vin thc hin: Trn Nam Hi Lp: 47N126Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi2.1.2. Ni dung tnh ton Tnh ton cc c trng kh tng thu vn cho d n ti gm cc ni dung chnh:- Tnh ton m hnh ma ti thit k.- Tnh ton ma nm ca khu vc.- Tnh ton bc hi v bc hi chnh lch khi c h.- Tnh ton cc c trng kh tng thu vn khc.- Tnh ton cc c trng thu vn thit k :+ Tnh ton dng chy nm thit k.+ Tnh ton dng chy l thit k.+ Tnh ton bn ct.2.2. Tnh ton ma ti thit k2.2.1. Mc ch, ngha v ni dung tnh ton 2.2.1.1. Mc ch, ngha 1. Mc ch Tnh ton ma ti thit k nhm mc ch tm ra tng lng ma v v m hnh phn phi ma v ng vi tn sut thit k phc v cho tnh ton ch ti ca cy trng.2. ngha T m hnh ma ti thit k tnh ton c c th xc nh c lng nc tha, thiu i vi tng loi cy trng trong tng thi on khc nhau. Do tnh ton ch ti cho cy trng hp l, m bo cung cp nc theo yu cu ca cy trng ng thi tit kim c lng nc ti.2.2.1.2. Ni dung tnh ton - Tnh ton m hnh ma thit k v chim.- Tnh ton m hnh ma thit k v ma.- Tnh ton m hnh ma thit k v ng.2.2.2. Chn trm tnh ton v tn sut thit k cho ti 2.2.2.1. Chn trm tnh ton 1. Nguyn tc chn trm tnh ton - Trm kh tng phi gn khu vc tnh ton, tt nht l nm trong khu vc tnh ton.- Trm kh tng phi c ti liu di (Ti liu t 20 nm tr ln).- Ti liu ca trm phi c chnh bin x l v m bo tnh chnh xc.2. Chn trm tnh ton Sinh vin thc hin: Trn Nam Hi Lp: 47N127Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiDo trm Phan Thit th hin c r nht ch ma c trng ca vng v c s liu quan trc kh di (74 nm t nm 1925 n nm 1998).Da trn nhng nguyn tc trn ta chn trm Phan Thit tnh ton ma ti cho khu vc.2.2.2.2. Chn tn sut thit k cho ti Tn sut thit k ma xc nh theo tiu chun xy dng Vit Nam TCXDVN 285 - 2002. Theo Bng 4.1 Mc m bo thit k ca cng trnh thu li - TCXDVN 285 - 2002, chn tn sut thit k cho ti l P = 75 %.2.2.3. Chn thi on tnh ton v phng php tnh ton 2.2.3.1. Chn thi on tnh ton - V chim xun t thng 1 n thng 5.- V ma t thng 6 n thng 10.- V ng t thng 9 n thng 1 nm sau.2.2.3.2. Phng php tnh ton1. Phng php phn tch nguyn nhn hnh thnh Phng php ny da vo vic phn tch nh hng ca cc nhn t kh hu v mt m n cc hin tng thu vn, tnh ton cc c trng thu vn bng phng trnh cn bng nc hoc cc m hnh, cc cng thc kinh nghim.Trong thc hnh phng php ny c phn chia c th nh sau:- Phng php lu vc tng t.- Phng php tng hp a l.- Phng php phn tch cn ngyn.2. Phng php thng k xc sut Phng php ny da vo l thuyt thng k xc sut, xem cc c trng thu vn l cc i lng ngu nhin, v ng tn sut v xc nh c tr s ca cc c trng thu vn ng vi mt tn sut thit k no .Vi trng hp tnh ma ti thit k, trm tnh ton c chn l Phan Thit c ti liu ma ngy kh di: T nm 1925 n nm 1998, v vy chn phng php tnh ton l phng php thng k xc sut.2.2.4. Tnh ton m hnh ma v thit k 2.2.4.1. Ni dung tnh ton theo phng php xc sut thng k 1. Bc 1: Chn mu : { }ii 1,nx2. Bc 2: Xy dng ng tn sut.a. V ng tn sut kinh nghim:- Thng k lng ma v hng nm (X v i).- Sp xp s liu lng ma v theo th t gim dn.Sinh vin thc hin: Trn Nam Hi Lp: 47N128Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Tnh lng ma v bnh qun nhiu nm theo cng thc :v X= nvii 11Xn(2 - 1)Trong :+v X : Lng ma v bnh qun nhiu nm ca v.+ n: S nm ti liu thu thp c.+ Xv i: Tng lng ma ca v nm th i.- Tnh tn sut kinh nghim: Tnh tn sut xut hin ca nhng tr s sp xp ny. Trong tnh ton thu vn thng s dng cc cng thc sau tnh tn sut kinh nghim:+ Cng thc trung bnh: m 0,5P .100%n(2 - 2)+ Cng thc s gia: m 0, 3P .100%n 0, 4+ (2 - 3)+ Cng thc vng s: mP .100%n 1+ (2 - 4)Trong : Pi: Tn sut kinh nghim ng vi gi trXv i n: S nm c chn. m: S th t ca lit quan trc Xv i c sp xp t ln n nh.nh gi v la chn cng thc tnh tn sut kinh nghim: Trong cc cng thc trn cng thc k vng thng cho kt qu an ton hn v c c s l lun, c s dng tnh ton dng chy l, ma l. Cng thc s gia thng tnh cho dng chy nm v ma nm.Do cng thc vng s an ton v c s dng nhiu trong thc t nn ta chn cng thc k vng tnh tn sut kinh nghim.- V ng tn sut kinh nghim: Chm cc im quan h gia lng ma v Xi vi tn sut Pi (%) ln giy tn sut (Giy Hazen) ta thu c ng tn sut kinh nghim.b. V ng tn sut l lun: Phng php mment: L phng php da hon ton vo l thuyt thng k tnh ra cc c trng thng k.- Tnh h s phn tn theo cng thc:( )n3ii 1vk 1Cn 1(2 - 5)Trong : ki = v ivXX l h s muyn lng ma.Sinh vin thc hin: Trn Nam Hi Lp: 47N129Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Tnh h s thin lch theo cng thc:( )( )n3ii 1s 3vk 1Cn 3 .C(2 - 6)T cc tham s X v, Cv, Cs v c ng tn sut l lun (Dng ng PIII).- u nhc im ca phng php:+ u im: Nu lit ti liu di, phn nh ng quy lut thng k ca thu vn th kt qu tnh ton s ph hp vi thc t cho kt qu tnh ton khch quan.+ Nhc im: Khi gp trng hp c im c bit xut hin khng x l c v thng cho kt qu thin nh khi tnh cc c trng thng k. Phng php 3 im:- Phng php 3 im da vo cc gi thit:+ ng tn sut l ng PIII.+ ng tn sut l lun v ng tn sut kinh nghim trng nhau hon ton.+ ng tn sut l lun v ng tn sut kinh nghim trng nhau khi c 3 im trng nhau, thng chn 3 im l cc im ng vi 5 %, 50 %, 95 %.- Cch v ng tn sut l lun:+ Chn trn ng tn sut kinh nghim 3 im X5%, X 50%, X95%.+ T gi thit ng tn sut l ng P III ta c :( )P s XX . C , P . m +(2 - 7)+ T (2 - 7) lp c h phng trnh:( )( )5 s X50 s X95 s XX .(C , 5). mX . C , 50 . mX . C , 95 . m + +' +(2 - 8)+ Gii h phng trnh (2 - 8) c Cs, ,mx.+ TnhvXCm T Cv, Cs, X v v c ng tn sut l lun.- u nhc im ca phng php:+ u im: Tnh ton nhanh, n gin.+ Nhc im: > Kt qu ph thuc vo ch quan ngi v.> Nhng im gia cc im ny cha chc ph hp.> Khi c t ti liu th khng khng ch cc im u v im cui dn n khng chnh xc. Phng php thch hp:Phng php thch hp cho rng c th thay i cc s c trng thng k trong chng mc nht nh sao cho m hnh xc sut gi thit thch hp vi chui s liu thc o.- Tnh Xv, Cv theo cng thc (2 - 1) v (2 - 5).Sinh vin thc hin: Trn Nam Hi Lp: 47N130Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Gi nguyn X v Cv, chn h s thin lch Cs = m.Cv , thay i m cho n khi ng tn sut l lun tng i ph hp vi ng tn sut kinh nghim.- u nhc im ca phng php:+ u im: Nu s dng chng trnh my tnh xy dng ng tn sut th phng php thch hp gip cho vic iu chnh s ph hp gia ng tn sut l lun v cc im kinh nghim nhanh v d dng.+ Nhc im: Vic tnh ton, nh gi ph hp gia ng tn sut l lun v ng tn sut kinh nghim cn ph thuc vo ch quan ngi v.=> Qua phn tch u nhc im ca cc phng php v ng tn sut l lun, trong n ny em chn v ng tn sut theo phng php thch hp v dng phn mm TSTV2002 tnh ton.3. Bc 3: Xc nh tr s thit k.Tra trn ng tn sut l lun gi tr thit k Xv P ng vi tn sut thit k P = 75 %.4. Bc 4: Xc nh m hnh phn phi thit k.a. Chn m hnh in hnh: Nguyn tc chn m hnh in hnh:- M hnh in hnh xy ra trong thc t.- C Xv h Xv P. Phng php chn m hnh in hnh: - Chn theo quan im bt li: i vi ti, ma phn phi bt li tc l vo nhng thi k cn nc th li ma t, vo nhng thi k cn t nc th li c nhiu ngy ma vi lng ma ln.+ u im: Cng trnh m bo c s an ton.+ Nhc im: Cng trnh c vn u t ln, hot ng hiu qu khng cao.- Chn theo quan im thng xuyn xut hin: L nhng trn ma thng xuyn xut hin trong ti liu quan trc. Chn trong s cc m hnh c Xv Xv P mt m hnh m dng phn phi ca n xut hin nhiu ln nht.+ u im: Cng trnh khng qu ln, hot ng hiu qu hn.+ Nhc im: Gp nhng nm c thi tit bt li th cng trnh kh c th m bo c.- Chn nm thc t: Chn nm thc t c phn phi xc sut nm gn nm thit k ng vi tn sut P.+ u im: Chn nhanh tnh ton n gin.+ Nhc im: Do s thay i tun theo quy lut t nhin nn nm thc t xut hin ri th khng xut hin li na.=> Qua vic phn tch u nhc im ca cc phng php chn m hnh in hnh, trong n ny em chn phng php chn m hnh in hnh theo quan im bt li.b. Thu phng:Sinh vin thc hin: Trn Nam Hi Lp: 47N131Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Tnh h s thu phng theo cng thc:K = h vP vXX(2 - 9)Trong :+ Xv P: Tng lng ma v ca nm thit k ng vi tn sut thit k P.+ Xv h: Tng lng ma v ca nm in hnh.- Xc nh m hnh ma v thit k:Xtk i = K.Xh i(2 - 10)Trong :+ Xh i: L lng ma ngy th i ca m hnh ma v in hnh.+ Xtk i : L lng ma ngy th i ca mo hnh ma v thit k.2.2.4.2. Tnh ton m hnh ma v thit k Chn trong lit ti liu thc o ca trm Phan Thit 28 nm tnh ton. Trong 28 nm ny c c nhng nm t nc, nm nc trung bnh, nm nhiu nc, s liu ca cc nm c lp nhau v c o trong iu kin tng i ging nhau. Nh vy mu c chn tho mn tiu chun chn mu.1. Xy dng ng tn sut kinh nghim Kt qu tnh ton cc im tn sut kinh nghim cho v chim, v ma, v ng cc ph lc 2 - 1, ph lc 2 - 2, ph lc 2 - 3.2. Xy dng ng tn sut l lun Xc nh cc thng s thng k:- Tnh X v = 28i 11. X28 v i- Tnh tn sut kinh nghim Pi theo cng thc (2 - 4): imP .100%n 1+, vi n = 28.- Tnh Cv theo cng thc (2 - 5): ( )n3ii 1vk 1Cn 1, vi n = 28.Do s dng phn mm c th iu chnh s ph hp gia ng tn sut l lun v ng tn sut kinh nghim d dng nn em chn phng php thch hp v ng tn sut.Kt qu tnh ton th hin trong cc ph lc 2 - 4, ph lc 2 - 5, ph lc 2 - 6.Thng s thng k ca cc v nh sau:- V chim: X v chim = 164,1 (mm); Cv = 0,5; Cs = 0,92.Sinh vin thc hin: Trn Nam Hi Lp: 47N132Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- V ma: X v ma = 814 (mm); Cv = 0,19; Cs = 0,42.- V ng: X v ng = 421,8 (mm); Cv = 0,37; Cs = 0,82.3. Xc nh tng lng ma v thit k Tra trn ng tn sut l lun ta xc nh c lng ma ng vi tn sut thit k P = 75% ca cc v nh sau:- V chim: Xv chim tk = 104,2 (mm).- V ma: Xv ma tk = 704,19 (mm).- V ng: Xv ng tk = 307,87 (mm).4. Tnh ton m hnh phn phi ma v thit k a. Chn m hnh in hnh:Da trn nguyn tc v phng php trn ta chn c m hnh ma in hnh ca cc v nh sau:- V chim: Nm 1990 c Xv chim h = 103,5 (mm).- V ma: Nm 1993 c Xv ma h = 695,6 (mm).- V ng: Nm 1989 - 1990 c Xv ng h = 302,4 (mm).b. Thu phng:- Tnh h s thu phng theo cng thc (2 - 9), ta c h s thu phng ca cc v nh sau:+ V chim: Kv chim = 1,01.+ V ma: Kv ma = 1,012.+ V ng: Kv ng = 1,018.- Tnh ton m hnh ma v thit k: C h s thu phng K nhn vo lng ma ngy ca nm in hnh theo cng thc (2 - 10) c m hnh ma v thit k.Kt qu ghi cc ph lc 2 - 7, ph lc 2 - 8, ph lc 2 - 9.2.3. Tnh ton ma nm ca khu vc 2.3.1. Mc ch, ngha v ni dung tnh ton 2.3.1.1. Mc ch, ngha 1. Mc ch xc nh c lng nc n lu vc v s thay i dng chy nm cn xc nh lng ma nm v phn phi ma nm ca lu vc.2. ngha Tnh ton lng ma nm thit k mt cch chnh xc s gip cho vic tnh ton ng c quy m kch thc cng trnh v mang li hiu qu cao v kinh t...2.3.1.2. Ni dung tnh ton Tnh ton lng ma nm trung bnh nhiu nm: X0.Sinh vin thc hin: Trn Nam Hi Lp: 47N133Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi2.3.2. Chn trm tnh ton Lu vc sng Quao pha thng lu c a hnh tiu biu ca vng rng ni, nm bn sn i n gi ca dy Trng Sn, do ch ma khc vi ch ma trn khu ti. C hai trm kh tng nm trn vng ni cao thuc lu vc tp trung nc ca sng Quao l trm Bo Lc (C ti liu t nm 1929 n nm 2000) v trm Di Linh (C ti liu di 54 nm nhng b t qung v ch c n nm 1993).Vy chn trm Bo Lc tnh ton ma nm ca khu vc.2.3.3. Tnh ma nm trung bnh nhiu nm Xo Ma nm trung bnh nhiu nm c tnh theo cng thc sau:X0= nnamii 1Xn(2 - 11)Trong :- X nm i: Lng ma nm ca nm th i trong lit ti liu tnh ton.- n : S nm tnh ton (n = 25 nm t nm 1976 n nm 2000).p dng cng thc (2 - 11) cho ti liu ma ca trm Bo Lc tnh c ma nm trung bnh nhiu nm ca lu vc l: X0 = 2822 (mm).2.4. Tnh ton lng ma mt ngy max T chui ti liu thc o 21 nm ma mt ngy max ca trm Bo Lc (T nm1989nm2009), dngphngphpthngkxydngngtnsut tng t nh cch tnh vi ma v cc mc trn.Xc nh cc thng s thng k theo phng php thch hp, c kt qu nh sau:- N = 21 nm (T nm 1989 2009).-1ngymax X = 118,90 (mm).- CV = 0,43.- CS = 1,29.Tra trn ng tn sut l lun, ng vi tn sut thit k P = 1 % c lng ma mt ngy max thit k l: X1ngy max = 282,71 (mm).Kt qu tnh tn sut kinh nghim v tnh tn sut l lun cc ph lc 2 - 10, ph lc 2 - 11.2.5. Tnh ton bc hi v bc hi chnh lch khi c h 2.5.1. Mc ch, ngha v ni dung tnh ton 2.5.1.1. Mc ch, ngha 1. Mc ch Tnh ton bc hi nhm mc ch phc v cho vic tnh ton tn tht nc trong khu ti v kho nc, tnh ton dung tch h.Sinh vin thc hin: Trn Nam Hi Lp: 47N134Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi2. ngha a. V mt k thut :Vic tnh ton bc hi c ngha quan trng, gip xc nh c lng nc tn tht trn khu ti v kho nc, t tnh ton ch ti ph hp, m bo cung cp nc theo yu cu ca cy trng, ng thi tnh ton iu tit h hp l, tn dng c lng nc n.b. V mt kinh t:Vic tnh ton bc hi chnh lch khi c h nh hng trc tip ti dung tch h yu cu, nh hng n quy m kch thc cng trnh => Quyt nh vn vn u t cho cng trnh.2.5.1.2. Ni dung tnh ton - Tnh ton bc hi trn khu ti.- Tnh ton bc hi chnh lch khi c h.2.5.2. Chn trm tnh ton Trn khu ti v cc vng xung quanh c cc trm kh tng nh : Phan Thit, Sng Lu,.... Trn lu vc h c cc trm: Bo Lc, Di Linh....Trong trm Phan Thit nm st khu ti, trm Bo Lc nm trn lu vc h, c ti liu kh di. V vy, chn trm Phan Thit tnh ton cho khu ti v trm Bo Lc tnh ton cho lu vc h.2.5.3. Tnh ton bc hi trn khu ti T ti liu thc o bc hi ca trm Phan Thit, tnh c bc hi trung bnh ngy nh Bng 2.12sau.Bng 2 .12. Bc hi trung bnh ngy ti Phan Thit (mm/ngy )ThngTrm1 2 3 4 5 6 7 8 9 10 11 12Phan Thit4,724,564,734,794,233,743,383,232,792,983,844,662.5.4. Tnh ton bc hi chnh lch khi c h Trn b mt lu vc c cc loi bc hi: - Bc hi mt nc Zn.- Bc hi mt t Z.- Bc hi qua l ca thm ph thc vt Zt.Tng hp ca ba loi bc hi trn l bc hi lu vc Zlv.Sinh vin thc hin: Trn Nam Hi Lp: 47N135Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiKhi xy dng h cha, phn din tch mt h b ngp nc c thm s tn tht nc do chnh lch gia bc hi mt nc v bc hi lu vc. Chnh lch bc hi c tnh bng: Zo = Zno -Zlvo(2 - 12)Trong :+ Zno: Bc hi mt nc trung bnh nhiu nm.+ Zlvo: Bc hi lu vc trung bnh nhiu nm.Zno v Zlvo ng vi thi on 1 nm.2.5.4.1. Tnh bc hi lu vc (Zlvo) Lngbchi bnhqunluvctrongthi giannhiunmctnht phng trnh cn bng nc:Zlvo = Xo - Yo(2 - 13)Trong :- X o: Lng ma nm trung bnh nhiu nm ca lu vc.X o ly theo kt qu tnh ton trm Bo Lc mc 2.3 trn:Xo = 2822 ( mm ).- Y o: Lng dng chy nm bnh qun nhiu nm ca lu vc.Yo = .Xo(2 - 14)Vi l h s dng chy, theo Quy phm Thu li C - 6 - 77 th c tnh theo cng thc sau:= a - 'obX(2 - 15)Trong :+ Xo: Lng ma nm trung bnh nhiu nm ca lu vc.+ a, b:Thng s ca quan h ly theo Bng 2 - 2 trang 19 ca Quy phm Thy li C - 6 - 77; a = 0,88; b = 616.Thay cc gi tr vo cng thc (2 - 15), ta c:= a - 'obX= 0,88 - 6162822 = 0,662.Thay = 0,662 vo (2 - 14) ta c:Yo = 0,662.2822 = 1868,16 (mm).Thay Xo v Yo vo (2 - 13) ta c:Zlvo = 2822 - 1868,16 = 953,84 (mm).2.5.4.2. Tnh bc hi mt nc (Z no)Trm Bo Lc c ti liu o bc hi ng Piche t trong lu kh tng, di 14 nm (T nm 1978 n nm 1991). Kt qu tnh ton lng bc hi thng, nm trung bnh ca 14 nm o c c Bng 2.13.Bng 2.13. Lng bc hi thng trung bnh nhiu nmSinh vin thc hin: Trn Nam Hi Lp: 47N136Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hiti Trm Bo Lc (mm).ThngI II III IV V VI VII VIII IX X XI XII NmZ76,2878,8185,6165,1151,3639,7038,5134,0633,1834,8744,3362,31644,13 tnh lng bc hi mt nc h phi chuyn i t bc hi ng Piche sang bc hi o bng thng t trn b nh sau:Zn = ZTh - b = Kc.Kn.Zp(2 - 16)Trong :+ Kc: H s hiu chnh khi chuyn t bc hi o bng ng Piche sang bc hi o bng thng t trong vn kh tng.Kc c xc nh bng th nghim, theo s liu th nghim ca trm Di Linh: Kc = 1,4.+ Kn: H s chnh khi chuyn t bc hi o bng thng t trong vn kh tng sang bc hi o bng thng t trn b.Kn cng c xc nh theo kt qu th nghim, Kn = 1,2 1,3, chn Kn = 1,3.+ Lng bc hi nm trung bnh nhiu nm theo ti liu ca trm Bo Lc l:Zp = 644,13 ( mm ).Thay vo (2 - 16) xc nh c lng bc hi mt nc:Zn = 1,4.1,3.644,13 = 1172,3 (mm).2.5.4.3. Tnh bc hi ph thm- Thay Zno v Zlvo vo cng thc (2 - 12) ta c: Zo = 1172,3 953,84 = 218,46 (mm).- Phn phi bc hi ph thm: tnh phn phi bc hi ph thm cho h cha, mn dng phn phi bc hi thng trung bnh nhiu nm ca trm Bo Lc bng cch thu phng vi h s:K =opZ 218, 46Z 644,13 = 0,339 (2 - 17)Kt qu tnh ton Bng 2.14.Bng 2.14. Phn phi bc hi ph thm khu vc h cha (mm).Thng I II III IV V VI VII VIII IX X XI XII Nm Z 25.9 26.7 29.0 22.1 17.4 13.5 13.1 11.5 11.2 11.8 15.0 21.1 218.462.6. Tnh ton cc c trng kh tng khc2.6.1. Nhit Kt qu tnh ton nhit trung bnh, cao nht v thp nht ti Phan Thit Bng 2.15.Bng 2.15. Nhit trung bnh, max, min ti Phan Thit (C).Sinh vin thc hin: Trn Nam Hi Lp: 47N137Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiThng I II III IV V VI VII VIII IX X XI XIITTbnh25,1 25,3 26,6 28,4 28,8 27,8 27,2 27,1 26,9 27,1 26,4 25,1Tmax32,9 33,7 32,4 37,2 37,2 35,8 35 34,2 35,5 33,8 34,2 33,6Tmin18 17,3 18,3 22,6 22,9 21,8 21,6 23,2 22,4 21,6 19,2 18,22.6.2. mBng 2.16. m tng i trung bnh thng ti Phan Thit (%).Thng I II III IV V VI VII VIII IX X XI XIIW 73 74 75 77 78 81 82 83 84 82 78 752.6.3. Tc giBng 2.17. Tc gi trung bnh thng ti Phan Thit (m/s).Thng I II III IV V VI VII VIII IX X XI XIIV 4,3 4,2 4,2 3,5 3,0 3,0 3,0 3,3 2,8 2,6 3,2 3,32.6.4. S gi nng Bng 2.18. S gi nng trung bnh ngy ti Phan Thit (gi/ngy).ThngI II III IV V VI VIIVIIIIX X XI XII TBS ginng9,419,379,829,858,087,197,286,666,526,667,348,788,082.7. Tnh ton cc c trng thu vn2.7.1. Phn tch ti liu dng chy v chn trm tnh tonTrn sng Quao khng c trm thu vn o c dng chy nn s phn tch ch dng chy n sng Quao gp kh khn. Trn lu vc dng chy n h sng Quao c mt s trm trn sng La Ng c ti liu tt, th hin c tnh cht dng chy trong vng, c th chn lm lu vc tng t, l cc trm:+ Trm Ph Din c din tch lu vc 3060 km2, c ti liu dng chy thc o t nm 1987 n nm 1991.+ Trm T Pao c din tch lu vc 2000 km2, c ti liu dng chy thc o t nm 1960 n nm 1964 v t nm 1973 n nm 1993.+ Trm i Nga c din tch lu vc 373 km2, c ti liu dng chy thc o t nm 1974 n nm 1993.Ngoi ra, gn lu vc sng Quao cn c lu vc sng Ly c din tch lu vc 964 km2, c ti liu dng chy t nm 1960 n nm 1963 v t nm 1978 n nm 1998.Sinh vin thc hin: Trn Nam Hi Lp: 47N138Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiDo chn phng php lu vc tng t tnh ton dng chy nm lu vc h.* Nguyn tc chn lu vc tng t:Lu vc c chn lm lu vc tng t khi lu vc v lu vc nghin cu tho mn cc iu kin sau:+ Nm trn cng mt lu vc sng.+ C cng hng gi gy ma.+ C cng dc a hnh, chnh lch gia cao trnh bnh qun khng vt qu 300 (m).+ C iu kin thm ph ging nhau.+ C din tch lu vc chnh lch nhau khng qu 5 ln.Lu vcsng Quao c din tch 296 (km2). Lu vc sng Quao v lu vc sng Ly cng nm trong h thng sng Ci, c cng hng gi gy ma l Ty v Ty Nam, c iu kin a hnh v thm ph tng t nhau, cng nm v sn ng ca dy Trng Sn. Lu vc sng Ly c din tch l 964 (km2), so vi din tch lu vcsng Quao khng chnh lch nhau qu 5 ln.Cc trm khc cng c cc iu kin khc tng t nhng din tch lu vc li ln hn nhiu lu vc h. Vy chn trm sng Ly lm lu vc tng t tnh ton dng chy cho lu vc h.2.7.2. Tnh ton dng chy nm ng vi tn sut thit k 2.7.2.1. Mc ch, ngha 1. Mc ch Tnh ton dng chy nm thit k nhm tm ra phn phi dng chy trong cc thng trn lu vc ca nm ng vi tn sut thit k.2. ngha a. V k thutL c s nh gi ngun nc trong khu vc, t xy dng c biu phn phi nc hp l.b. V kinh tnh hng trc tip n quy m kch thc cng trnh, vic tnh ton khng chnh xc c th dn n cng trnh qu ln hoc qu nh. Cng trnh qu ln s lng ph vn u t, cng trnh qu nh s khng tn dng c ht kh nng ca ngun nc v mt an ton trong qu trnh hot ng.2.7.2.2. Ni dung tnh ton - Tnh dng chy nm thit k.- Tnh ton phn phi dng chy nm thit k.2.7.2.3. Tnh dng chy nm thit k Sinh vin thc hin: Trn Nam Hi Lp: 47N139Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi1. Tnh dng chy chun a. Tnh cho lu vc tng t sng LyT chui s liu dng chy thc o di 21 nm ca trm sng Ly (19781998) tnh c:- Lu lng dng chy chun: Qoa = nii 1Qn 14,51 ( m3/s ) (2 - 18)Trong :+ Qi: L tr s lu lng bnh qun nm ca trm sng Ly.+ n: l s nm thc o (n = 21 nm).- Tng lng dng chy chun:Woa = Qoa.31,5.106 = 14,51.31,5.106 =457,065 (m3) (2 - 19)- Muyn dng chy chun:Moa = 3oaQ .10F314, 51.1015, 05964(l/s.km2)(2 - 20)Trong : F l din tch lu vc tng t, F = 964 (km2).- Lp dng chy chun: Yoa = 3 3oaQ .31, 5.10 14, 51.31, 5.10474,134F 964 (mm)(2 - 21)b. Tnh cho lu vc h cha:Mn muyn dng chy chun ca lu vc tng t tnh muyn dng chy ca lu vc h cha theo cng thc:Mo = K.Moa(2 - 22)Trong :+ Mo: L muyn dng chy chun ca lu vc nghin cu.+ Moa: L muyn dng chy chun ca lu vc tng t.+ K: L h s hiu chnh lu vc tng t sang lu vc nghin cu.K c xc nh theo cng thc:K = naFF _ ,(2- 23)Trong :+ F: L din tch ca lu vc nghin cu.+ Fa: L din tch ca lu vc tng t.+ n: L h s m, c th chn trong khong (0,2 0,25), y ta chn n = 0,2.Thay tt c vo (2 - 23) ta c:K = 0,22960, 79964 _ ,.Thay tt c cc gi tr ca K v Moa vo (2 - 22) ta c:Sinh vin thc hin: Trn Nam Hi Lp: 47N140Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiMo = 0,79.15,05 = 11,89 (l/s.km2).Suy ra:Qo = o3 3M .F 11,89.2963, 5210 10 (m3/s).Wo = Qo.31,5.106 = 3,52.31,5.106 = 110,88.106 (m3).Yo = 3oW 110,88.10374, 6F 296 (mm).2. Tnh dng chy nm thit k a. Tnh cho lu vc sng LyV ng tn sut l lun lu lng bnh qun nm lu vc sng Ly bng phng php thch hp, vi cc thng s thng k:- N = 21 nm (1978 1998).-Q = 14,51 (m3/s).- Cv = 0,33.- CS = m.Cv = 4. Cv = 1,32.Tra trn ng tn sut l lun ng vi tn sut thit k P = 75% c lu lng dng chy nm thit k ca lu vc tng t: Q 75% = 10,96 (m3/s).Kt qu tnh ton tn sut kinh nghim v tn sut l lun ph lc 2 - 12, ph lc 2 - 13.b.Tnh cho lu vc h cha - Tnh h s phn tn Cv theo cng thc:Cv = a - 0,0631.lg(F + 1) (2 - 24)Trong :+ a: L thng s a l mn ca lu vc tng t sng Ly.a sng Ly = CVsng Ly + 0,0631.log( Fsng Ly + 1 ) (2 - 25) a sng Ly = 0,33 + 0,0631.log( 964 + 1) = 0,518.+ F: L din tch lu vc h, F = 296 (km2).Suy ra:Cv h = 0,518 - 0,0631.lg( F + 1) Cv h = 0,518 - 0,0631.lg(296 + 1) = 0,36.- Lu lng bnh qun nm tnh trn: Qo = 3,52 (m3/s).- Chn CS = 4.CV = 4.0,36 = 1,44 theo t s gia CS v CV lu vc tng t.- S dng phn phi xc sut Pearson III tnh ton c lu lng dng chy nm thit k (P = 75 %):Q75% = KP.Qo(2 - 26)Trong : KP l h s muyn ca ng tn sut Pearson III.Tra Ph lc 3 Gio trnh Thy vn cng trnh, ng vi CS = 4.CV c :KP = 0,748.Vy lu lng dng chy nm thit k ca lu vc h cha:Q75% = 0,748.3,52 = 2,63 (m3/s).Sinh vin thc hin: Trn Nam Hi Lp: 47N141Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi2.7.2.4. Tnh ton phn phi dng chy nm thit k 1. Tnh cho lu vc tng t sng Ly Phn phi dng chy theo nm thy vn ca lu vc sng Ly c xc nh theo trnh t cc bc sau:- V ng tn sut v xc nh c lu lng dng chy nm thit k ca lu vc tng t nh mc III, c Qap = 10,96 (m3/s).- Chn nm in hnh: + Theo quan im: > Nm in hnh c: Qh Qap> tng o c (c trong lit ti liu o c).+ Theo phng php thng xuyn xut hin.Cc nm chn: > Nm 1978 c: Q = 11,04 (m3/s).> Nm 1981 c: Q = 11,09 (m3/s).> Nm 1991 c: Q = 10,47 (m3/s).Trong cc nm trn, nm 1991 l nm c lu lng bt li i vi yu cu dng v s dng nc. Trong nm ny ma kit ko di v lu lng ma kit thp, c n 9 thng c lu lng nh l cc thng sau: 1, 2, 3, 4, 5, 6, 8, 11, 12.V vy ta chn nm in hnh l nm 1991, c: Qh = 10,47 (m3/s).- Phn phi dng chy nm thit k: Lu lng cc thng c tnh theo cng thc sau:Qtki = K.Qhi(2 - 27)Trong , h s thu phng K c tnh theo cng thc:K = apqdhQ10,961,0468Q 10,47(2 - 28)Bng 2.21. Phn phi dng chy nm thit k lu vc sng Ly Thngc trngI II III IV V VI VII VIII IX X XI XIIQ ( m3/s ) 2.45 1.13 0.81 0.45 4.88 6.27 16.64 7.14 32.87 48.78 7.52 2.60( % ) 1.86 0.86 0.61 0.34 3.71 4.77 12.65 5.43 24.99 37.09 5.71 1.972. Tnh cho lu vc h chaMn h s phn phi dng chy cc thng trong nm thit k ca lu vc sng Ly, ta c dng phn phi dng chy nm thit k ca lu vc h cha.Tnh ton phn phi lu lng:Qi = 12.Qp.i(2 - 29)Trong :- Qi: L lu lng thng th i trong nm thit k.Sinh vin thc hin: Trn Nam Hi Lp: 47N142Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Qp: L lu lng bnh qun nm thit k.- i: L t l phn phi ca thng th i trong nm thit k.Bng 2.22. Phn phi dng chy nm thit k lu vc h cha.Thng I II III IV V VI VII VIII IX X XI XIIQi ( m3/s ) 0.59 0.27 0.19 0.11 1.17 1.50 3.99 1.71 7.89 11.70 1.80 0.622.6.3. Tnh ton dng chy l 2.6.3.1. Mc ch, ngha 1. Mc ch Tm ra c cc c trng ca l: Lu lng nh l, tng lng l v ng qu trnh l thit k.2. ngha - V mt k thut Tnh ton dng chy l nhm phc v cho vic xc nh dung tch phng l ca h cha v l c s xc nh quy m, kch thc cng trnh x l.- V mt kinh t Tnh ton dng chy l c ngha quan trng, vic tnh ton sai dn n cng trnh ln qu s gy lng ph vn u t, cng trnh nh qu s khng an ton, khi gp l ln cng trnh c th b ph hy, gy ngp lt, thit hi ln v kinh t, x hi.2.6.3.2. Ni dung tnh ton+ Tnh ton lu lng nh l: Qmp.+ Tnh ton tng lng l: Wmp.+ Tnh ton qu trnh l thit k (Q ~ t)l TK.2.6.3.3. Chn tn sut v phng php tnh ton 1. Chn tn sut tnh ton Cn c vo din tch phc v ca h cha (ti cho khong 4200 ha t canh tc) S b chn cp cng trnh l cp III.Theo TCXDVN 285 - 2002, tn sut tnh ton l i vi cng trnh cp III l: P = 1 %.2. Phng php tnh ton Lu vc h cha v vng xung quanh khng c ti liu l thc o. Do tnh ton l cho lu vc h phi s dng cc cng thc kinh nghim.Ngoi ra khi tnh ton c th tham kho cc c trng kh tng trong lu vc h t ti liu kh tng thc o ca cc trm xung quanh v thng ngun h.Sinh vin thc hin: Trn Nam Hi Lp: 47N143Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi2.6.3.4. Tnh ton c th 1. Tnh ton lu lng l ln nht (Qmp) Lu vc sng Quao c din tch F = 296 (km2) > 100 (km2). Do , tnh l cho lu vc h phi s dng cng thc trit gim:Qmp = q100.nF100

,_

.p.F. (2 - 30)Trong : - q100: Muyn nh l ca din tch gc bng 100 (km2). q100 c tnh vi tn sut 10% v c v thnh bn ng tr. Vi lu vc nghin cu, v khng c bn ng tr q100 nn an ton hn chn q100 = 8000 (l/s - km2) = 8 (m3/s - km2).- p: H s i tn sut,pcng c tng hp t ti liu thc t, vi sng min ni chn p = 1,636.- F: Din tch lu vc, F = 296 (km2).- : Hstrit gimnhldonhhngcaaohtrnluvc. Xc nh theo cng thc sau: =h aof C. 11+ ( 2 - 31 )Vi :+ fao h : Din tch ao h tng i trong lu vc, fao h = FFh ao i vi lu vc h, fao h = 0,1.+ C : H s phn nh kh nng iu tit ca h ao. C = 0,2 vi vng ma l ngn, C = 0,1 vi vng ma l ko di. Vi lu vc sng Quao c dc a hnh ln, ma l ngn nn C = 0,2.- n : H s trit gim, xc nh t bn phn vng h s trit gim : n = 0,25.Thay s vo ( 2 - 30 ) tnh c: Qmp = 8.25 , 0296100

,_

. 1,636 . 296 . 11 0,2.0,1 + =2895,62 ( m3/s ).2. Tnh ton tng lng l thit k Wmp Cng thc tng qut tnh Wmp l:Wmp = 103.hp. F (2 - 32)Trong :- F: Din tch lu vc, F = 296 (km2).- hP: Lp dng chy l thit k. Theo X - k - lp - sky :hP = .( H p - Ho) (2 - 33)Tra Bng 6 - 13Gio trnh Thy vn cng trnh, ng vi lu vc sng ng Nai c : hP = 0,64.(H p - 25).Sinh vin thc hin: Trn Nam Hi Lp: 47N144Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Tnh H p theo cng thc:H p = (t) . Hnp(2 - 34)Vi:+ Hnp: Lng ma ngy ln nht thit k ca lu vc vi P = 1%.Hnpxc nh bng cch v ng tn sut lng ma ngy ln nht ca trm ma i din, theo tnh ton mc 2.4 c: Hnp = 282,71 (mm).+ (t): Tung ng cong ly tch ma ph thuc cc phn khu khc nhau tra theo Bng 6 - 4 Gio trnh Thy vn cng trnh, vi = sl thi gian tp trung nc trong sng.sxc nh theo cng thc:s = s1/3 1/4s s max1000.Lm.J .Q(2 - 35)Trong : * Ls: Chiu di sng, Ls = 10,5 (km).* ms: Thi gian tp trung nc trong sng, tra quy phm C - 6 - 77, vi sng min ni ms = 7.* Js: dc lng sng Js = 4.* Qmax: Lu lng nh l, Qmax = 2895,62 (m3/s).Thay vo (2 - 35) tnh c:s= 1/3 1/41000.10,57.0,004 .2895,62 = 1288,2 (pht).Tra Bng 6 - 4 c (t) = 1,1.Thay vo (2 - 34) tnh c :H p = (t) . Hnp = 1,1 . 282,71 = 311 (mm). Thay vo (2 - 33) c:hp = 0,64.(H p -25) = 0,64.(311 -25) = 183,04 (mm).Thay vo (2 - 20) tnh c tng lng l thit k:Wmp = 103.hp. F = 103. 183,04 . 296 = 54,2.106 (m3).3. Tnh ton ng qu trnh l thit k Trong n ny, n gin em chn dng ng tam gic tnh ton ng qu trnh l.- Tnh thi gian l theo Qmp v Wmp:Tl = mpmp2.WQ = 62.54,2.102895,62 = 37,44.103 (s) = 10,4 (gi) (2 - 36)Sinh vin thc hin: Trn Nam Hi Lp: 47N145Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiQ(m /s)T(gi)3Tl xTQmax- T s gia thi gian l ln v l xung: = lxTT(2- 37) ph thuc vo din tch lu vc v cc nhn t iu tit ca lu vc. i vi lu vc nh t iu tit, = 1,5 2. Chn = 2.Thi gian l ln: Tl = 31 Tl =31 . 10,4 = 3,4 (gi).Thi gian l xung:Tx = Tl - T1 = 10,4 - 3,4 = 7 ( gi ).2.6.4. Tnh ton bn ct 2.6.4.1. Mc ch, ngha1. Mc ch Tnh ton bn ct nhm xc nh tng lng bn ct n h trong 1 nm.2. ngha Tnh ton din bin bi lng h cha theo thi gian phn tch hiu qu s dng dung tch hiu dng ca h cha.2.6.4.2. Ni dung tnh tonCc c trng biu th ca dng bn ct l:+ Lu lng bn ct: R (kg/s).+ Lng ngm ct: = Q10 . R3 (g/m3). (2 - 38) Vi Q: Lu lng bnh qun trong thi gian tnh R.+ S phn b bn ct trn mt ct v theo thi gian.+ Thnh phn ht ca bn ct. y tnh ton bn ct ch yu phc v tnh bi lng kho nc nn ch tnh bn ct bnh qun nhiu nm.1. Tnh lu lng bn ctLu vc nghin cu khng c ti liu o c bn ct nn phi tnh ton bn ct da vo cc cng thc kinh nghim.Sinh vin thc hin: Trn Nam Hi Lp: 47N146Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiVi cc lu vc min Nam c F > 100 (km2), lu lng bn ct l lng c tnh theo cng thc:Ro = 0,197.Q37 , 1o(2 - 39)Trong : Qo: Lu lng dng chy chun ca lu vc h cha. tnh c Qo = 3,52 (m3/s).Thay vo (2 - 38) tnh c: Ro = 0,197.3,521,37 = 1,105 (kg/s).- Lng ngm ct: o = oo1000.RQ = 1000.1,1053,52 = 313,92 (g/m3).2.Tnh bi lng kho nc i vi h cha va v nh, c th tnh lng bn ct bi lng hng nm theo cng thc:Vbc = Vll + Vd(2 - 40)Trong :- Vbc l th tch bn ct bi lng hng nm.-Vll l th tch bn ct l lng lng xung h hng nm, tnh theo cng thc:Vll= (1 - )oR.31,5.103 (m3) (2 - 41)Vi: + : Phn bn ct ht b tho ra khi h lc l, tnh theo phn th tch chung ca bn ct. Chn = 0,4.+ Ro: Lu lng bn ct, tnh c trn Ro = 1,105 (kg/s).+ : Khi lng ring ca bn ct, = 0,5 0,7 (tn/ m3).Chn = 0,6 (tn/ m3).Thay vo (2 - 41) tnh c : Vll = (1 - 0,4).1,1050,6.31,5.103 = 34807,5 (m3).- Vd l th tch bn ct di y lng xung h hng nm.Vdc th xc nh theo t l % ca Vll:Vd= K . Vll(2 - 42)* i vi sng ng bng K = 1 10 %. * i vi sng min ni K = 10 80 %. Chn K = 22%.Th tch bn ct di y lng xung kho nc hng nm l:Vd= 40% .Vll = 0,22 . 34807,5 = 7657,65 (m3)Th tch bn ct lng xung kho nc hng nm:Vbc = Vll + Vd = 34807,5 + 7657,65 = 42465,15 (m3).Sinh vin thc hin: Trn Nam Hi Lp: 47N147Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiChng 3. Tnh ton yu cu nc ca khu vc3.1. Mc ch, ngha v ni dung tnh ton3.1.1. Mc ch, ngha3.1.1.1. Mc ch Tnh ton yu cu nc ca khu vc c c s xut phng n cp nc, tnh ton phi hp ngun nc nhm xc nh c quy m, kch thc cng trnh, m bo p ng c nhu cu dng nc ca nng nghip v cc ngnh khc nh : sinh hot, thy in, xy dng, giao thng thy, cng nghip,....3.1.1.2. ngha - V mt k thut: L c s c k hoch cp nc hp l, gip cy trng t nng sut v cht lng sn phm cao. ng thi c bin php tha mn yu cu dng nc ca cc ngnh khc nh : sinh hot, thy in, xy dng, giao thng thy, cng nghip,....- V mt kinh t: Tnh ton xc nh c quy m, kch thc cng trnh ph hp tit kim vn u t nhng vn m bo tnh hiu qu ca cng trnh.3.1.2. Ni dung tnh ton - Tnh ton ch ti cho la trng v chim.- Tnh ton ch ti cho la trng v ma.- Tnh ton ch ti cho cy trng v ng.- Tnh ton yu cu nc cho sinh hot.3.2. Tnh ton ch ti cho cc loi cy trng 3.2.1. Mc ch, ngha v ni dung tnh ton 3.2.1.1. Mc ch, ngha 1. Mc ch Tnh ton ch ti cho cc loi cy trng nhm xc nh c ch ti thch hp trong sut qu trnh sinh trng v pht trin cho tng loi cy trng ng vi iu kin a hnh v kh hu nht nh. Sinh vin thc hin: Trn Nam Hi Lp: 47N148Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi2. ngha Ch ti l ti liu quan trng trong cng tc quy hoch, tnh ton lu lng thit k knh mng v lp k hoch dng nc trong giai on qun l vn hnh.3.2.1.2. Ni dung tnh ton 1. Thi gian cn ti (ngy ti chnh).2. Mc ti mi ln:Mc ti mi ln l lng nc ti mi ln cho mt n v din tch cy trng no .Mc ti thng c biu th bng:- Lng nc, k hiu m (m3/ha).- Lp nc, k hiu h (mm).Gia mc ti m (m3/ha) v lp nc trn mt rung h (mm) c mi lin h nh sau:m = 10.h (m3/ha) khi h tnh bng (mm) (3 - 1)3. S ln ti trong sut qu trnh sinh trng ca cy trng, k hiu n (ln).4. Thi gian ti mi ln :Thi gian thc hin ti ht mc ti mi ln, thng k hiu l t ( ngy ).5. Mc ti tng cng : Mc ti tng cng l lng nc ti tng cng cho mt n v din tch cy trng trong sut thi gian sinh trng ca cy trng , thng c gi l mc ti ton v, k hiu l M ( m3/ha ).Mc ti tng cng bng tng cc mc ti mi ln :M = m1 + m2 + m3 +. + mn ( 3 - 2 )6. H s ti : Hsti llulngnccnti chomt nv dintchtrngtrt, thng c k hiu l q ( l/s-ha ).Gi s ta thc hin mc ti m ( m3/ha ) trong t ( ngy ) th h s ti c tnh bng cng thc : q = m86,4.t( l/s-ha )( 3 - 3 )3.2.2. Nguyn l tnh tonNguyn l chung tnh ton ch ti cho cy trng l nguyn l cn bng nc, l s cn bng nc gia lng nc n (gm lng nc ma, lng nc c sn) v lng nc i (gm lng nc ngm v lng nc bc hi). Khi tnh ton ch ti cho cc loi cy trng khc nhau th ta p dng nguyn l chung c th vo tng trng hp.3.2.3. Cc ti liu dng trong tnh ton3.2.3.1. Ti liu v thi v cy trng v loi cy trng Sinh vin thc hin: Trn Nam Hi Lp: 47N149Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi1. Ti liu v thi v cy trng- V chim xun trng la, thi gian t 13/01 20/05.- V ma trng la, thi gian t 26/06 13/10.- V ng trng ng, thi gian t 29/09 11/01 nm sau.2. Ti liu v loi cy trng a. Ti liu v la chim Bng 3.1. Thi v v cng thc ti tng sn la v chimSTT Thi on sinh trngThi gian Cng thc ti(mm)H sKcT n S ngy1 Ngm rung 13/01 15/01 3 30 - 50 12 Cy - bn r 16/01 22/01 7 30 - 50 0,463 Bn r - nhnh 23/01 06/02 15 30 - 50 0,944 nhnh - ng ci 07/02 19/03 41 30 - 50 1,145 ng ci - lm ng 20/03 18/04 30 30 - 50 1,196 Lm ng - ngm sa 19/04 08/05 20 30 - 50 0,857 Ngm sa - thu hoch 09/05 20/05 12 30 - 50 0,66- Hnh thc canh tc: Lm i.- Hnh thc gieo cy: Tun t.- Thi gian gieo cy: tg = 15 (ngy).b. Ti liu v la maBng 3.2. Thi v v cng thc ti tng sn la v ma.STT Thi on sinh trngThi gian Cng thc ti(mm)H sKcT n S ngy1 Cy - bn r 26/06 30/06 5 40 - 70 0,662 Bn r - nhnh 01/07 10/07 10 40 - 70 0,873 nhnh - ng ci 11/07 14/08 35 40 - 70 1,24 ng ci - lm ng 15/08 13/09 30 40 - 70 1,195 Lm ng - ngm sa 14/09 01/10 18 40 - 70 0,966 Ngm sa - thu hoch 02/10 13/10 11 40 - 70 0,92- Hnh thc canh tc: Lm dm. - Hnh thc gieo cy: Gieo cy ng thi.c. Ti liu v ng v ngSinh vin thc hin: Trn Nam Hi Lp: 47N150Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiBng 3.3. Thi v v cng thc ti tng sn ng v ngSTTThi onsinh trngThi gian sutng tnui cy(cm)Ncngmcung cp(mm)H scytrngKcCngthcti(% A)T nSngy1 Gieo - mc mm 29/09 05/10 7 50 0 0,67 55 - 802 Mc mm - ba l 06/10 17/10 12 50 0 0,87 55 - 803 Ba l - tr c 18/10 11/12 55 50 0 1,25 55 - 804 Tr c - phi mu 12/12 17/12 6 50 0 1,12 55 - 805 Phi mu - chn sa 18/12 30/12 13 50 0 0,85 55 - 806 Chn sa - chn vng 31/12 11/01 12 50 0 0,6 55 - 803.2.3.2. Ti liu v tnh cht t Bng 3.4. Cc ch tiu c l ca t canh tcSTT Cc c trng K hiu Tr s n v1 Ch s ngm 0,52 rng Ao40 %3 H s ngm ban u K130 mm/ngy4 H s ngm n nh K2,5 mm/ngy5 m sn c o30 %A6 Chiu su tng t canh tc H 0,5 m7 m ti a max95 %A3.2.3.3. Ti liu v kh tng Cc ti liu v kh tng s dng trong tnh ton ch ti cho cy trng c tnh ton Chng II, gm c:- M hnh ma v thit k.- Nhit bnh qun thng, nhit ti cao v nhit ti thp ti trm Phan Thit.- m bnh qun thng, m ln nht v m nh nht ti trm Phan Thit.- Ti liu v bc hi.- Ti liu v gi.- Ti liu v s gi nng.Sinh vin thc hin: Trn Nam Hi Lp: 47N151Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi3.2.4. Xc nh lng bc hi mt rungLng bc hi mt rung thc t i vi cy trng c xc nh theo cng thc tng qut:ETc = Kc.ETo(3 - 4)Trong :- ETc: Lng bc hi mt rungthc t theo thi gian tnh ton (mm).- ETo: Lng bc hi cy trng tham kho, tnh theo cc cng thc kinh nghim (mm).- Kc: H s cy trng, ph thuc vo loi cy trng v giai on sinh trng, xc nh qua thc nghim.Do , nh lng bc hi mt rung thc t ETc ta ch vic xc nh lng bc hi chun ETo. Hin nay c rt nhiu cng thc kinh nghim xc nh ETo nh cc cng thc: Charov, Blaney - Criddle, Penman, Bc x.Trong , cng thc Penman cho kt qu chnh xc cao v tnh ton dc trn nhiu yu t kh hu. V vy trong n ny em s dng cng thc Penman tnh ton ETo. Cng thc Penman c dng:ETo = C. [ ]n a dW.R (1 W).f(v).(e e ) + ( mm/ngy ) (3 - 5)Trong :- W: Yu t hiu chnh hiu qu ca bc x i vi bc hi do nhit v cao khu ti, W = f (Nhit , cao khu ti), W c th tra Bng 3.4Gio trnh Quy hoch v thit k h thng thu li tp I.- Rn: Chnh lch gia bc x tng v bc x gim ca sng ngn v sng di (mm/ngy).Rn = Rns - RnL(3 - 6)- Rns: Bc x ca mt tri c gi li sau khi phn x i vi mt t trng trt (mm/ngy).Rns = (1 - ).Rs(3 - 7)- : H s phn x b mt din tch trng trt, theo FAO th = 0,25.- Rs: Bc x mt tri (mm/ngy).Rs = an0, 25 0, 5. .RN _+ ,(3 - 8)- n: S gi chiu sng thc t.- N: S gi chiu sng theo kinh v v , N c th tra Bng 3.5Gio trnh Quy hoch v thit k h thng thu li tp I.- Ra: Bc x lp bin ca lp kh quyn (mm/ngy), Ra = f (v , thng) v Ra tra Bng 3.8 Gio trnh Quy hoch v thit k h thng thu li tp I.- RnL: Bc x to ra bi nng lng ht c ban u (mm/ngy).RnL = f(t).f(ed).f(nN) (3 - 9)Sinh vin thc hin: Trn Nam Hi Lp: 47N152Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- f(t): Hm hiu chnh v nhit .f(t) = 4 9118.(t 273) .10L+(3 - 10)Vi: L = 59,7 - 0,055.t (3 - 11) t: Nhit bnh qun ngy.- f(ed): Hm hiu chnh v p sut kh quyn. f(ed) = 0,34 - 0,044.de(3 - 12)- ed: p sut hi nc thc t nhit khng kh trung bnh (mbar).ed = ea.rH100(3 - 13)- fnN _ , : Hm hiu chnh v s gi nng.fn n0,1 0, 9.N N _ _ + , ,(3 - 14)- ea: p sut hi nc bo ho, c quan h vi nhit khng kh, tra theo Bng 3.7 Gio trnh Quy hoch v thit k h thng thu li tp I.- Hr: m tng i trung bnh ca khng kh (%).- C: H s hiu chnh v s b tr ca tc gi ban ngy v ban m cng nh s bin i ca bc x mt tri v m tng i ln nht ca khng kh, tra theo Bng 3.6 Gio trnh Quy hoch v thit k h thng thu li tp I.- f(u): Hm hiu chnh v tc gi.f(u) = 0,35.(1 + 0,54.U2) (3 - 15)- U2: Tc gi cao 2 m, khi cao 2 m phi hiu chnh. Do , khi tnh ton s dng h thc: U2 = K.Uh(3 - 16)- Uh: Tc gi cao h mt (m/s).- K: H s hiu chnh < 1, traBng 3.1Gio trnh Quy hoch v thit k h thng thu li tp I.Kt qu tnh lng bc hi ETo ph lc 3 - 1.3.2.4. Tnh ton ch ti cho la3.2.4.1. Tnh ton ch ti cho la v chim 1. Ch canh tc i vi ch canh tc l lm i, tu theo mi hnh thc lm i m c quan im xc nh ch ti khc nhau. Hin nay c hai quan im xc nh ch ti cho la lm i l:a. Quan im I: Tnh ton ch ti vi hnh thc gieo cy ng thi. C c im l: Sinh vin thc hin: Trn Nam Hi Lp: 47N153Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi- Trong thi k lm i do sau khi phi i cho nc vo ton b cnh ng nn vic cung cp nc qu cng thng, lng nc cn cung cp rt ln.- Lng nc hao v ch do ngm v bc hi qu ln mt khc i hi nhiu nhn lc trong gieo cy v a nc vo rung.b. Quan im II: Tnh ton ch ti vi hnh thc gieo cy tun t. C c im l:- Vic gieo cy tun t tin hnh trong thi gian tg bng cch mi ngy gieo cy mt phn din tch.- Chun b gieo cy n u cho nc vo n y, khng cho nc trn lan vo ton b cnh ng. Nh vy, vic cung cp nc khng qu cng thng, trnh c tn tht nc do ngm v bc hi mt cch v ch cc tha cha cy.Do , chn quan im I tnh ton ch ti cho la chim vi hnh thc gieo cy tun t.c im ca ch ti cho la v chim theo hnh thc gieo cy tun t : Thi gian lm i v thi gian ti dng trn cnh ng l xen k nhau. Tha cy trc chnh trc, tha cy sau chn sau nn thi v trn cnh ng khng ng u. Trn cnh ng c nhiu ch ti khc nhau. Ch ti thit k phi l tng hp t cc ch ti khc nhau.2. Phng php tnh ton C hai phng php tnh ton ch d ti l: Phng php gii v phng php gii tch.- Phng php gii: Phng php ny s dng th xc nh mc ti v thi gian ti.-Phngphpgii tch:Da vo thik sinh trngvphttrincacy trng lp bng gi thit mc ti tm ra ch ti ph hp.Phng php gii tch tnh ton n gin, nhanh v c tnh chnh xc cao. V vy trong n ny em s dng phng php gii tch tnh ton ch ti cho la chim.3. Tnh ton lng nc hao Lng nc hao trn rung la gm hai thnh phn:- Lng nc hao do ngm : Lng nc ngm trn rung la ch yu ph thuc vo t ai, th nhng, mc nc ngm. Lng nc ny bao gm ngm bo ho trong thi gian u a nc vo rung v ngm n nh trong sut thi gian sinh trng ca la.+ Giai on ngm bo ho : L giai on nc ngm vao t lm cho m t tng t m ban u o n m bo ho bh.+ Giai on ngm n nh : L giai on sau khi m t n bh nc ngm do tc dng ca trng lc.- Lng nc hao do bc hi mt rung : Lng nc hao do bc hi mt rung ch yu ph thuc vo iu kin kh hu v cy trng.Sinh vin thc hin: Trn Nam Hi Lp: 47N154Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc HiQu trnh bc hi din ra theo 2 giai on :+ Giai on ngm rung : Do cha c cy trng nn bc hi mt rung l bc hi nc t do.+ Giai on sinh trng ca cy trng: Bc hi mt rung gm c bc hi qua khong trng v bc hi qua l cy.Vi c im ca phng php gieo cy tun t th cc thnh phn trong lng nc hao s thay i theo mt qu trnh no . Cc dng ng qu trnh ny thay i tu thuc vo thi gian gieo cy tg, thi gian xy qu trnh hao nc trn khu rung c cy xong trong 1 ngy, cng hao nc eh, din tch gieo cy trong mt ngy . C cc dng ng nc hao sau:- Khi tg > th, c dng ng qu trnh nc hao loi I:Wmax = hhgt10.e .t (m3/ha-ngy) (3 - 17)- Khi tg < th, c dng ng nc hao loi II:Wmax = h10.e(m3/ha-ngy) (3 - 18)- Khi tg = th, c dng ng nc hao loi III:Wmax = h10.e(m3/ha-ngy) (3 - 19)a. Tnh lng tn tht thm do ngm bo ho:S ngm ht trn rung la xy ra khi mi bt u cho nc vo rung sau khi cy v phi rung xong. y l giai on nc ngm vo t lm cho tng t trn nc ngm t ti trng thi bo ho nc.Qu trnh ny c c trng bi 2 i lng:- Tc ngm ht Vt hay h s ngm ht Kt.- Thi gian ngm ht hay thi gian lm bo ho tng t mt rung tb.Thi gian ngm bo ho c xc nh theo cng thc sau:tb = 11ooA.H.(1 )K 1 1 ](3 - 20)Trong : + A: rng t, c tnh bng % th tch t, A = 40 %.+ H: su tng t trn mc nc ngm, H = 500 (mm).+ o: m trong tng t trc khi a nc vo rung, o = 30 (%A).+ Ko: H s ngm ht bnh qun trong n v thi gian th nht.Ko = 1K1(3 - 21)Vi: K1: Cng ngm ht cui n v thi gian th nht. K1 = 30 (mm/ngy). : Ch s ngm, = 0,5.Sinh vin thc hin: Trn Nam Hi Lp: 47N155Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hi Ko = 1K 30601 1 0, 5 (mm/ngy).Thay cc s liu vo cng thc (3 - 23) ta c:tb = 11 0,50, 4.500.(1 0, 3)601 1 ]= 5,444 (ngy) Chn tb = 6 (ngy).Trong trng hp ny, thi gian ngm ht tb= 6 (ngy) < tg= 15 (ngy) nn dng ca ng qu trnh ngm ht l ng loi I.Cng ngm ht bnh qun trong thi gian hao nc tb:eh = Knbh = obA.H.(1 ) 0, 4.500.(1 0, 3)23, 333t 6 (mm/ngy)(3 - 22)Lng nc ngm lm bo ho mt n v din tch 1 ha trong thi gian tb:Wmax = 10.eh.bgt 610.23, 333. 93, 332t 15 (m3/ngy) = 9,333(mm/ngy)(3 - 23)b.Tnh lng nc hao do ngm n nh:Giai on ngm n nh trn rung la xy ra sau qu trnh ngm bo ho. Lc ny lng nc mt rung ngm xung t ch yu do tc dng ca trng lc.Thi gian ngm n nh c xc nh theo cng thc:t = tn + tstr - tb(3 - 24)Trong :- tn: Thi gian ngm rung, tn = 3 (ngy).- tstr: Thi gian sinh trng, tstr = 125 (ngy).- tb: Thi gian bo ho tng t, tb = 6 (ngy).Thay s vo cng thc (3 - 27) ta c:t = 3 + 125 - 6 = 122 (ngy).Do t= 122 (ngy) > tg= 15 (ngy) nn ng qu trnh hao nc trong giai on ngm n nh l ng loi II.Cng ngm bnh qun trong giai on ngm n nh:eh = K.H aH+(3 - 25)Trong :- K: H s ngm n nh, K = 2,5 (mm/ngy).- H: Chiu su tng t canh tc, H = 500 (mm).- a: Lp nc mt rung bnh qun trong thi on tnh ton.a = max mina a 50 30402 2+ + (mm).Thay tt c vo (3 - 28) c: eh = 500 402, 5. 2, 7500+ (mm/ngy).Lng nc hao ln nht do ngm n nh:Wmax = 10.eh = 10.2,7 = 27 (m3/ha-ngy) = 2,7 (mm/ngy).Sinh vin thc hin: Trn Nam Hi Lp: 47N156Lp d n u t h thng ti h P1_Phan Thit GVHD: PGS.TS.Phm Ngc Hic. Tnh lng nc hao do bc hi mt rung ng vi cc thi on sinh trng ca la:Bc hi mt rung c c trng bi cc i lng sau:- Thi gian xy ra qu trnh hao nc tr din tch gieo cy th.- Thi gian hao nc trn ton b khu ti Th = th + tg(3 - 26)Cng bc hi mt nc trung bnh c xc nh theo cng thc:ETc = hTo1h bhi chETe e K .T (3 - 27)Trong :- Kc: H s cy trng.- ETo: Lng bc hi tham kho.+ Khi tg > th th Wmax = hhgt10.e .t (m3/ha-ngy).+ Khi tg <