column base plate.pptx

8/20/2019 column base plate.pptx

1/34

DESIGN OF COLUMN BASEPLATES AND STEELANCHORAGE TO CONCRETE

Khaled Eid


2/34

Outline

Introdution Ba!e "late!

Material

De!i#n u!in# AISC Steel De!i#n Guide Conentri a$ial load A$ial load "lu! %o%ent A$ial load "lu! !hear

Anhor Rod! T&"e! and Material! De!i#n u!in# ACI A""endi$ D

Ten!ion Shear


3/34

Introdution

Ba!e "late! and anhor rod! are o'ten thela!t !trutural !teel ite%! to (e de!i#ned(ut the )r!t ite%! re*uired on the +o(!ite

There'ore the de!i#n o' olu%n (a!e "lateand onnetion! are "art o' the ritial "ath


4/34

Introdution

Anhor! to a""ear in onrete dra,in#!,ith loation o' eah anhor in $ and &diretion

Pede!tal !hould (e de!i#ned to !uit the!u""ortin# olu%n and anhor!

U!uall& allo, 'or enou#h ed#e di!taneo' -d (olt

U!uall& u!e to nut! to a.oid !li"


5/34

Introdution

/a!t %a+orit& o' olu%n (a!e "late onnetion!are de!i#ned 'or a$ial o%"re!!ion ,ith little orno u"li't

Colu%n (a!e "late onnetion! an al!o tran!%it

u"li't 'ore! and !hear 'ore! throu#h0 Anhor rod! Bearin# end "late Shear lu#! under the (a!e "late or e%(eddin# the

olu%n (a!e to tran!'er the !hear 'ore1 Colu%n (a!e "late onnetion! an al!o (e u!ed

to re!i!t ,ind and !ei!%i load! De.elo"%ent o' 'ore ou"le (et,een (earin# on

onrete and ten!ion in !o%e or all o' the anhor rod!


6/34

Introdution

Anhor rod! are needed 'or all (a!e "late!to "re.ent olu%n 'ro% o.erturnin# durin#on!trution and in !o%e a!e! to re!i!t

u"li't or lar#e %o%ent! Anhor rod! are de!i#ned 'or "ullout and

(rea2out !tren#th u!in# ACI 345 A""endi$D

Critial to "ro.ide ,ell6de)ned7 ade*uateload "ath ,hen ten!ion and !hear loadin#,ill (e tran!'erred throu#h anhor rod!

In !ei!%i 8one! the "ede!tal !hould arr&91: the 'atored de!i#n load


7/34

Introdution

Grout i! needed to ad+u!t the le.el Grout to tran!'er the load 'ro% !teel "late

to 'oundation

Grout !hould ha.e de!i#n o%"re!!i.e!tren#th at lea!t t,ie the !tren#th o''oundation onrete

;hen (a!e "late! (eo%e lar#er than-


8/34

Ba!e "late Material!

Ba!e "late! !hould (e ASTM A3- %aterialunle!! other #rade i! a.aila(le

Mo!t (a!e "late! are de!i#ned a! to %ath

the "ede!tal !ha"e A thi2er (a!e "late i! %ore eono%ial

than a thinner (a!e "late ,ith additional!ti>ener! or other rein'ore%ent!


9/34

Ba!e Plate De!i#n


10/34

De!i#n o' A$iall& Loaded Ba!ePlate!

Re*uired "late area i! (a!ed on uni'or%allo,a(le (earin# !tre!!1 For a$iall& loaded(a!e "late!7 the (earin# !tre!! under the (a!e"late i! uni'or%

A9 ? di%en!ion! o' onrete !u""ortin# 'oundation

A4 ? di%en!ion! o' (a!e "late Mo!t eono%ial "late our! ,hen ratio o'

onrete to "late area i! e*ual to or #reaterthan @ Ca!e 4

;hen the "late di%en!ion! are 2no,n it i! not

`

1

2`max 7.185.0 ccc p f

A A f f ≤×=φ


11/34

Ca!e 40 A9 @A4

41 Deter%ine 'atored load Pu91 Calulate re*uired "late area A4 (a!ed on %a$i%u%

onrete (earin# !tre!! ' "?41' ,hen A9?@A4

31 Plate di%en!ion! B N!hould (e deter%ined!o % n area""ro$i%atel& e*ual

`)(1 7.16.0 c

u

req f

P

A ×=

∆+= )(1 req A N 2

8.095.0 f bd −=∆

N

A B

req)(1=


12/34

Ca!e 40 A9 @A4

@1 Calulate re*uired (a!e "late thi2ne!!

,here l i! %a$i%u% o' % and n

:1 Deter%ine "ede!tal area7 A9

2

95.0 d N m

−=

2

8.0 f b Bn

−=

BN F

P l t

y

u

90.0

2min =

BN A 42 =


13/34

Ca!e 90 Pede!taldi%en!ion! 2no,n

41Deter%ine 'atored load Pu91 The area o' the "late !hould (e e*ual tolar#er o'0

31 Sa%e a! Ca!e 4

@1 Sa%e a! Ca!e 4

2

`

2

185.060.0

1

×=

c

u

f P

A A

`1 7.16.0 c

u

f P A×=


14/34

De!i#n o' Ba!e Plate! ,ithMo%ent!

E*ui.alent eentriit&7 e7 i! alulated e*ual to%o%ent M di.ided (& a$ial 'ore P

Mo%ent and a$ial 'ore re"laed (& e*ui.alenta$ial 'ore at a di!tane e 'ro% enter o' olu%n

S%all eentriitie!

e*ui.alent a$ial 'orere!i!ted (& (earin# onl& Lar#e eentriitie! nee!!ar& to u!e an anhor

(olt to re!i!t e*ui.alent a$ial 'ore


15/34

De!i#n o' Ba!e Plate ,ith S%allEentriitie!

I' eN- o%"re!!i.e (earin# !tre!! e$i!te.er&,here

I' e i! (et,een N- and N9 (earin# our! onl&o.er a "ortion o' the "late

AB P f 21 =

I

Mc

BN

P f ±=2,1


16/34

De!i#n o' Ba!e Plate ,ith S%allEentriitie!

41 Calulate 'atored load Pu and %o%ent Mu

91 Deter%ine %a$i%u% (earin# "re!!ure7 '"

31 Pi2 a trial (a!e "late !i8e7 B and N

@1 Deter%ine e*ui.alent eentriit&7 e7 and%a$i%u% (earin# !tre!! 'ro% load7 ' 41 I' ' 4

'" #o to ne$t !te"7 i' not "i2 di>erent (a!e"late !i8e

:1 Deter%ine "late thi2ne!!7 t"

41 M"lu i! %o%ent 'or 4 in ,ide y

pl u

p F

M t

90.0

4=

`

1

2` 7.185.0 ccc p f A

A f f ≤×=φ


17/34

De!i#n o' Ba!e Plate ,ithShear Four "rini"al ,a&! o' tran!'errin# !hear 'ro%

olu%n (a!e "late into onrete

41 Frition (et,een (a!e "late and the #rout oronrete !ur'ae

The 'rition oeient µ i!


18/34

De!i#n o' Shear Lu#!

41 Deter%ine the "ortion o' !hear ,hih ,ill (ere!i!ted (& !hear lu#7 /l#u

91 Deter%ine re*uired (earin# area o' !hear lu#

31 Deter%ine !hear lu# ,idth7 ;7 and hei#ht7 H

@1 Deter%ine 'atored antile.ered end %o%ent7 M l#u

:1 Deter%ine !hear lu# thi2ne!!

`

lg

lg 85.0 c

u

f

V

A φ =

+

=

2lg

lg G H W

V M uu

y

u

F

M t

90.0

4 lglg =


19/34

Anhor Rod!

T,o ate#orie! Ca!t6in "lae0 !et (e'ore the onrete i!

"laed

Drilled6in anhor!0 !et a'ter the onrete i!hardened


20/34


21/34

Ca!t6in Plae Anhor Rod!

;hen rod! ,ith thread! and nut are u!ed7 a%ore "o!iti.e anhora#e i! 'or%ed Failure %ehani!% i! the "ull out o' a one o'

onrete radiatin# out,ard 'ro% the head o'the (olt or nut

U!e o' "late ,a!her doe! not add an&inrea!ed re!i!tane to "ull out

Hoo2ed (ar! ha.e a .er& li%ited"ullout !tren#th o%"ared ,ith that o'

headed rod! or threaded rod! ,ith

a nut o' anhora#e


22/34

Anhor Rod Plae%ent

Mo!t o%%on )eld "ro(le% i! "lae%ent o'anhor rod!

I%"ortant to "ro.ide a! lar#e a! hole a!

"o!!i(le to ao%%odate !ettin# tolerane! Fe,er "ro(le%! i' the !trutural !teel detailer

i!!ued anhor (olt la&out 'or "lain# theanhor! 'or% hi! 3d %odel


23/34

Anhor Rod La&out

Should u!e a !&%%etrial "attern in(oth diretion! ,here.er "o!!i(le

Should "ro.ide a%"le learane di!tane

'or the ,a!her 'ro% the olu%n Ed#e di!tane "la&! i%"ortant role 'or

onrete (rea2out !tren#th

Should (e oordinated ,ith rein'orin#!teel to en!ure there are nointer'erene!7 %ore ritial in onrete"ier! and ,all!


24/34

De!i#n o' Anhor Rod! 'or Ten!ion ;hen (a!e "late! are !u(+et to u"li't 'ore Tu7

e%(ed%ent o' anhor rod! %u!t (e he2ed 'orten!ion

Steel !tren#th o' anhor in ten!ion

A!e ?e>eti.e ro!! !etional area o' anhor7 AISC Steel Manual Ta(le 645

'ut? ten!ile !tren#th o' anhor7 not #reater than 41'& or 49: 2!i

Conrete (rea2out !tren#th o' !in#le anhor inten!ion

he' ?e%(ed%ent

2?9@ 'or a!t6in "lae anhor!7 4 'or "o!t6in!talled anhor!

ψ 97 ψ 3 ? %odi)ation 'ator!

ut se s f A N =

5.1`

ef cb h f k N =b No N

cb N

A

A N

32ψ ψ

=

i ' h d '


25/34

De!i#n o' Anhor Rod! 'or Ten!ion ANo?Pro+eted area o' the

'ailure !ur'ae o' a !in#leanhor re%ote 'ro% ed#e!

AN?A""ro$i%ated a! the (a!e

o' the retilinear #eo%etrial)#ure that re!ult! 'ro%

"ro+etin# the 'ailure !ur'aeout,ard 41:he' 'ro% the

enterline! o' the anhor

E$a%"le o' alulation o' AN ,ith ed#e

di!tane 4 le!! than 41:he'

29 ef No h A =

)5.12)(5.1( 1 ef ef N hhc A ×+=

i ' h d '


26/34

De!i#n o' Anhor Rod! 'or Ten!ion Pullout !tren#th o' anhor

No%inal !tren#th in ten!ion Nn ? %inN!7

N(7 N"n

Co%"are u"li't 'ro% olu%n7 Tu7 to Nn I' T

u

le!! than φNn

o2

I' Tu #reater than φNn %u!t "ro.ideten!ion rein'orin# around anhor rod!or inrea!e e%(ed%ent o' anhor rod!

`

4 8 cbrg pn f A N ψ =

D i ' A h R d '


27/34

De!i#n o' Anhor Rod! 'orShear ;hen (a!e "late! are !u(+et to !hear 'ore7 /u7 and

'rition (et,een (a!e "late and onrete i!inade*uate to re!i!t !hear7 anhor rod! %a& ta2e!hear

Steel Stren#th o' !in#le anhor in !hear

Conrete (rea2out !tren#th o' !in#le anhor in !hear

ψ -7 ψ ? %odi)ation 'ator!

do ? rod dia%eter7 in

l ? load (earin# len#th o' anhor 'or !hear not to e$eed 5do7 in

b

vo

vcb V

A

AV 76ψ ψ =

5.1

1

`

2.0

7 c f d d

l V co

o

b

=

ut se s f AV =

D i ' A h R d '


28/34

De!i#n o' Anhor Rod! 'orShear A.o?Pro+eted area o' the 'ailure

!ur'ae o' a !in#le anhor re%ote'ro% ed#e! in the diretion"er"endiular to the !hear 'ore

A.?A""ro$i%ated a! the (a!e o' a

trunated hal' "&ra%id "ro+etedon the !ide 'ae o' the %e%(er

E$a%"le o' alulation o' A. ,ith ed#e

di!tane

9 le!! than 41:4

( ) 215.4 c Avo =

)5.1(5.1 211 ccc Av +=

D i ' A h R d '


29/34

De!i#n o' Anhor Rod! 'orShear Pr&out !tren#th o' anhor

No%inal !tren#th in !hear /n ? %in/!7

/(7 /"

Co%"are !hear 'ro% olu%n7 /u7 to /n I' /

u

le!! than φ/n

o2

I' /u #reater than φ/n %u!t "ro.ide !hearrein'orin# around anhor rod! or u!e!hear lu#!

cbcpcp N k V =

C (i d T i d


30/34

Co%(ined Ten!ion andShear Aordin# to ACI 345 A""endi$ D7 anhor rod!

%u!t (e he2ed 'or interation o' ten!ile and!hear 'ore!

2.1≤+n

u

n

u

V

V

N

φ φ


31/34

Re'erene!

A%erian Conrete In!titute ACI 3456


32/34

Co%%on %i!ta2e!


33/34

Care'ul ,hen on!iderin# the loationo' anhor! to onrete ,all!


34/34

Bolt! %i!! ali#n%ent or la!h ,ith#u!!et "late

Documents

column base plate.pptx