Good Engineering Practice at Site

1Good Engineering PracticeAt Sites

C. Material testing

B. Construction tolerances

D. Concrete

E. Detailing

A. Getting ready

2A. Getting Ready

a. Study all drawings, report any discrepancies

b. Prepare site layout with temporary facilities & program

c. Set-out centerlines,boundaries & disturbances to existing services

d. Take dated photographs of all adjoining buildings prior to commencement of work at site and afterwards

e. Keep weather records countersigned by the Consultants site representative

f. Prepare shop drawings of critical joints etc.

g. Co-ordinate work & arrange meetings with other contractors

h. Participate in progress & other meetings with Consultants

3STEMS STEMS CONSULTANTS (PTE) LTD159, Model Farm Road, Colombo 08

No Name Address Telephone Fax

1

1234

123

1

1

1

A B C123

Lift Suppler

Contractor

Electrical Engineer

Structural Engineers

Services Consultants

Project :PROPOSED 35 STOREY TOWER AT LOT A1 & B3, GALLE ROAD, COLOMBO 03.

Project Data SheetE-mail

Client

Architects \ Lead Consultant

Consultants

a. Prepare project data sheet

STEMS CONSULTANTS (PTE) LTD

159, Model Farm Road, Colombo 08. Building

Date : 18/08/2007 at : 10 .30 am / pm at Site / Office

1 0 Attendance SheetNo Name Organization Signature Tel / Fax

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

PILING PROGRESS MEETING NO

APARTMENT BUILDING

PROPOSED 35 STOREY RESIDENTIAL TOWER WITH 3 STOREY BASEMENT

AT LOT A1 & B3 , GALLE ROAD, COLOMBO 03.

STEMSProject

Prepare an attendance sheet

4STEMS ProjectSTEMS CONSULTANTS (PTE) LTD159, Model Farm Road, Colom bo 08. Building

Notes Of Meeting Attended (NOMA) Meeting No: 06Date: 18/08/2007 Time: 10.30 am / pm Venue : Site Office

Notes Taken by: S A Karunaratne

Item Description Action by

APARTMENT BUILDING

PROPOSED 35 STOREY TOWER, LOT A1 & B3, GALLE ROAD, COLOMBO 03

b. Prepare NOMA

c. Furnish copy same day to Head-office

d. Act prior to receipt of official minutes

a. Do not take Notes Of Meetings Attended, NOMAon pieces of paper

STEMS ProjectSTEMS CONSULTANTS (PTE) LTD159, Model Farm Road, Colom bo 08 Client Imperial Tea Exports (Pvt) Ltd, 121A, Biyagama Rd, Peliyagoda

Items to be discussed at First Site Meeting Meeting No:01

Date: 2004 - 11 - 06 Time: 10.30 am / pm Venue : Site Office

Item Action by

(1)

(2)

(3)

(4)

(5)

(6) Names of Ready-Mix suppliers, if to be changed advance notice and furnish details in Item 5

(7) If constituent materials are changed Contractor should furnish test data and compatibility

(8)

(9)

(10)

(11)

(12)

(13)

(14)

(15)

(16)

(17)

(18)

(19)

(20)

(21)

Blending & Warehouse Building, 151, Biyagama Road, Peliyagoda

Construction drawings to be checked by Contractor and inform Consultant if more details are required

Main orthogonal grids to be checked by Consultant after Contractor setout the buildings

Contractor to furnish Consultant a plan of temporary facilities and locations with dimensions

Notes Taken by:

Description

Performance, Advance Payment Bonds and Insurance Cover from Contractor

Mix design, 40 No. Test cube results, material tests and admixtures, extreme care with sand.

Approval of fill material to be used in ground improvements

Approval for concreting.

Test cubes, 06 numbers, 02 for 07 day tests and 04 for 28 days tests, proper identification, proper

moulds, proper storage, curing and due date testing

Cover blocks - Same concrete grade with small chips

Structural Steel fabrication

Consultant's site staff office

Temporary power, telephones, fax, photocopying facilities, water and toilets etc

Typical format of records

Site Instructions and Variation Orders

Master programme and Cash Flow Chart and "S" Curve

Biweekly detailed programme matching with master programme, monthly progress report

Electrical Drawings from Contractor to be checked by Consultant

Date of commencement, Completion date, Time left, Extensions

Site Safety, Accidents at site

Items to be Discussed at First Meeting

5STEMS ProjectSTEMS CONSULTANTS (PTE) LTD159, Model Farm Road, Colombo 08. Building

CONCRETING APPROVAL FORM - ADate: 18/08/2007 Time: am / pm Venue : Site

1 Location

2 Station From: Axis: Grid: To: Axis: Grid:

3 Level From: To:

4 Preparation of screed / Concrete surface:

5 Form work:

a) Quality :

b) Rigidity :

c) Verticality :

6 Reinforcement:

a) Number :

b) Size :

c) Pitch :

d) Spacer blocks :

e) Cleaning :

7 Concrete Vibrators in working order available at siNo: Size:

8 Concrete cube moulds available at site: No:

9 Approved for concreting Signature

Name

Organisation STEMS CONSULTANTS (PTE) LTD

10 Not approved for concreting Reasons

Signature

Name

Organisation STEMS CONSULTANTS (PTE) LTD

11 Date of concreting Date:

Concrete test cubes cast No:

12 Cube Test Results

PROPOSED 35 STOREY TOWER, LOT A1 & B3, GALLE ROAD, COLOMBO 03.

APARTMENT BUILDING

7 day 28 day

a. Concreting Approval Form A

STEMS ProjectSTEMS CONSULTANTS (PTE) LTD159, Model Farm Road, Colom bo 08. Building

CONCRETING APPROVAL FORM - BDate: 18/08/2007 Time: am / pm Venue : Site

1 Location

2 Station From: Axis: Grid: To: Axis: Grid:

3 Level From: To:

4 Electrical Works

a) Electrical conduits & inserts:

b) Earthing provisions:

5 Approved Signature

Name

Organisation

6 Water Supply, Waste Water, Sewerage & Fire Protection works

a) Water Supply Pipe Layout/ducts: Pipe dia:

b) Waste Water Pipe Layout/drains: Pipe dia:

c) Sewerage Pipe Layout/ducts: Pipe dia:

d) Fire Protection Pipe Layout/ducts: Pipe dia:

7 Approved Signature

Name

Organisation Building Services Consultants

Signature

Singapore Piling

Name of Resident Agent

PROPOSED 35 STOREY TOWER, LOT A1 & B3, GALLE ROAD, COLOMBO 03

APARTMENT BUILDINGb. Concreting Approval Form B

6No. QA - 1 ACTIVITY

2 DATE

3 STATUS OF ACTIVITY

4 ONGOING WORK:

5 REF DRAWINGS:

6 REF. SPECIFICATION

7 COMMENTS

8 QUALITY ASSURANCE PROCEDURES Implemented Yes / No

9 ITEMS TO BE INSPECTED

10 INSPECTION REQUIRED Date Time

11

Construction Engineer / KSJ Site Manager /KSJ

12

Reviewed . Resident Engineer, Vallibel Lanka Ltd

QUALITY ASSURANCE REPORT

COLOMBO 1.

PROPOSED ENTERTAINMENT COMPLEX AT COLOMBO 3.

VALLIBEL LANKA LTD27-02, EAST TOWER

WORLD TRADE CENTREECHELON SQUARE

STEMS STEMS CONSULTANTS (PTE) LTD159, Model Farm Road, Colombo 08

Issued to: .. Copies to: UDA / CCS / T&SW

Prepared by: . Checked by : Approved by :..Mr S A Karunaratne Mr Gamini Jayasinghe Mr Nihal FernandoStems Consultants (Pte) Ltd Engineer's Representative Engineer

Date : . Date : . Date : ..

Madiwela Government Project

Security Building

SITE INSTRUCTION / VARIATION ORDER NO. S/

Item Action by Description of Work

Project

Building

Request for Inspection a. Format for Site Instructions

b. Make notes on drawing about site instruction

STEMS Time Sheet No 27STEMS CONSULTANTS (PTE) LTD159, Model Farm Road, Colombo 08

Name S A KarunaratneWeek Ending 2001- 07 - Position Team LeaderDay

Date 1 2 3 4 5 6 01 02 03 04 05 06 07 08 09 10 11 12 13 14 N O T

MON

2TUE

3WED

4THU

5FRI

6SAT

7SUN

8

Stage: 1. Sur/Invest 2. F Study 3. Design 4. Tender 5. Construction 6. Follow up

Job Description: 01. Adm / P Mtg / Mtd 02. Data / Job Planning / Briefing 03. Estimate / Cost 04. Designs 05. Draughting06. Specifications 07. BOQ's 08. Checking 09. Amendments 10. Printing & Binding11. Correspondence 12. Site Inv / M Testing / Testing 13. Site Inspection 14. Supervision

8Total HoursHOURS Stage Job Description

Building:

Project:

Residence & Security Staff Buildings

Madiwela Government Project

Time Sheet

7240 piles

MADIWELA GOVERNMENT PROJECT PROGRAMME OF WORKS FOR THE SECURITY STAFF COMPLEX

New

Yea

r H

olid

ays

Tender Document Approval by TEC

Tender Document Approval by TEC

Tender & Award For Building Works

Test Pile Installation & ReportPile Drawings & Tender Documents

Piling Tender & Award

Pile Installation

Building Design & Drawings

May2001

JuneJanuary February March April2000ITEMS OF WORK

Preparation of Tender Documents

November December

Programme of Works Up-to Building Tender

B. Construction tolerances

8Construction tolerances Misalignment of

Face of Building in planFace of Building in plan 5mm in 3000mm & max. 25mm5mm in 3000mm & max. 25mmNothing over boundary line Nothing over boundary line

Footings & Pile CapsFootings & Pile Capsa) a) wrtwrt C L of wall or columnC L of wall or columnb) Dimension in planb) Dimension in planc) Thicknessc) Thickness

2% of footing width; max. 50mm2% of footing width; max. 50mm+ 50mm ; + 50mm ; -- 10mm10mm+ 10% ; + 10% ; -- 5% ; max. + 10mm5% ; max. + 10mm

VerticalVerticala) Lines & surfaces of wall, a) Lines & surfaces of wall, columcolumb) Column & wall from plumbb) Column & wall from plumb

5mm in 5000mm & max. 12mm5mm in 5000mm & max. 12mm12mm in 30m: 20mm in 60m &12mm in 30m: 20mm in 60m &25mm up to 90m and above25mm up to 90m and above

Max. deviation of mean levelMax. deviation of mean levela)a) 3m height from lower floor 3m height from lower floor b)b) 6m height from lower floor6m height from lower floorc)c) 12m height from lower floor12m height from lower floord)d) In any upper floorIn any upper floor

6mm6mm12mm12mm20mm20mm20mm 20mm ctdctd --

Levels & GradientLevels & Gradienta) In 3m length of floor & beam soffita) In 3m length of floor & beam soffitb) In 6m length of floor & beam soffitb) In 6m length of floor & beam soffitc) For the whole lengthc) For the whole length

6mm6mm10mm10mm20mm20mm

Lintels, sills, parapets & groovesLintels, sills, parapets & groovesa) In a 6m lengtha) In a 6m lengthb) In 12m or moreb) In 12m or more

6mm horizontally6mm horizontally10mm horizontally10mm horizontally

Cross SectionsCross Sectionsa) Dimensiona) Dimension < 150mm< 150mmb) Dimension 150mm & > 150mmb) Dimension 150mm & > 150mm

+10mm ; +10mm ; --3mm3mm+12mm; +12mm; --6mm6mm

OpeningsOpeningsa) Sizes and locationsa) Sizes and locationsb) Additional margins for windows, doors b) Additional margins for windows, doors

or lift door installations Contractors or lift door installations Contractors responsibilityresponsibility

+6mm ; +6mm ; --6mm6mm

StairsStairsa) Deviation in risersa) Deviation in risers

b) Deviation in treadsb) Deviation in treads

In consecutive step + 2mmIn consecutive step + 2mmIn any flight, + 6mmIn any flight, + 6mmIn consecutive step + 3mmIn consecutive step + 3mmIn any flight, + 6mmIn any flight, + 6mm

9Removal of formwork & props minimum periods recommended

Beam sides, walls & columns (unloaded)Beam sides, walls & columns (unloaded) 24 hours24 hours

Slab (props left in place)Slab (props left in place) 4 days4 days

Beam Beam soffitssoffits (props left in place)(props left in place) 7 days7 days

Props to slabs between beamsProps to slabs between beams 14 days14 days

Props to beams & flat slabsProps to beams & flat slabs 14 days14 days

Props to cantileversProps to cantilevers 28 days28 days

C. Material Testing

10

Proctor Compaction Test

(a) Standard (S P C T)

(b) Modified (M P C T)

Soil TestsProctor

CBR

(a). 5.5 lb hammer; 12 drop; volume of 4 mould 944cm3

(b). 10 lb hammer; 18 drop; volume of 6 mould 2123cm3

11

(b) Proctor Compaction Apparatus for Heavy Compaction

(a) Proctor Compaction Apparatus for LightCompaction

(a)(b)

(a)

12

(1) Optimum Water Content 13.1%

(2) Maximum Dry Density 1.87 g/cm3

13

Moisture Content in percent for complete saturation = Wsat

Density of water in g/cm3 = wSpecific gravity of soil = Gs

Dry density of soil in g/cm3 = dWsat = (w/d 1/Gs) d = w/(w/100 + 1/Gs)

Moisture Content in percent = w

Wet density of soil in g/cm3 =

S P C T is generally used in small fills, parking lots and for building structures

M P C T is generally used in large fills, roads, Airport Runways and Concrete Parking Aprons and for building structures

Field compaction done with different type of rollers

(a) Clayey and Silty Soils use Sheepsfoot rollers

(b) Granular Soils use Smooth-drum or Vibratory rollers

%age of Optimum Compaction attained in the field is Relative Density or R (%)

1) R(%) for S P C T is 95% - 100%

2) R(%) for M P C T is 90% - 95%

3) R(%) for granular fills is 95% - 100%

Common R(%) field test is Sand Replacement Method

14

California Bearing Ratio (CBR) testing (Laboratory) apparatus

CBR

California Bearing Ratio (CBR) testing apparatus

15

California Bearing Ratio (CBR) testing apparatus in the field

CBR relationship of force & penetration of a cylindrical plunger of 3 inch2 at a standard rate into soil. 0.05 per minute

CBR in essence evaluate strength of subgrades

High CBR lower pavement thickness & vise versa

CBR valueCBR value SubgradeSubgrade strengthstrength

3% and less3% and less PoorPoor

3% 3% -- 5%5% NormalNormal

5% 5% -- 15%15% GoodGood

Other field apparatus used to determine CBR

(a)Hand held Mexe Penetrometer indicate CBR values upto 3m depth

(b) Dynamic Cone Penetrometer

could be used to evaluate results using a formula

16

Stress Penetration Curves of CBR Tests

Reinforcement & Concrete

17

R/F bar tests to BS 4449a) Proof / Yield stress > Characteristic strength of 460 or 250 N/mm2

b) Tensile strength > Proof / Yield stress

c) %age elongation 12% for 460A & 14% for 460B

d) %age elongation 22% for MS - 250

e) Stress ratio (TS / YS) >= 1.05 for 460A & 1.08 for 460B

f) Stress ratio (TS / YS) >= 1.15 for MS

460A rib pattern 460B rib pattern

Bar Diameter ( Bar Diameter ( ) mm) mm66 88 1010 1212 1616 2020 2525 3232 4040

0.2220.222 0.3950.395 0.6160.616 0.8880.888 1.5791.579 2.4662.466 3.8543.854 6.3136.313 9.8649.864

99 6.56.5 6.56.5 4.54.5 4.54.5 4.54.5 4.64.6 4.54.5 4.54.5

0.2420.242 0.4210.421 0.6560.656 0.9280.928 1.6501.650 2.5772.577 4.0274.027 6.5976.597 10.30810.308

0.2020.202 0.3690.369 0.5760.576 0.8480.848 1.5081.508 2.3552.355 3.6813.681 6.0286.028 9.4209.420

Reinforcement weight - kg / m

3rd row :- Average weight

4th row :- + Tolerance

5th row :- Upper limit kg/m6th row :- Lower limit kg/m

18

Chemical analysis and Carbon equivalenceElementElement Grade 250Grade 250 Grade 460Grade 460

% Max% Max % Max% Max

CarbonCarbon 0.250.25 0.250.25

SulphurSulphur 0.0600.060 0.0500.050

PhosphorusPhosphorus 0.0600.060 0.0500.050

NitrogenNitrogen 0.0120.012 0.0120.012

Max. Carbon equivalent Max. Carbon equivalent values (CEV)values (CEV)

0.420.42 0.510.51

CEV = C + Mn/6 + (Cr + Mo + V)/5 + (Ni +Cu)/15

STEMS STEMS CONSULTANTS (PTE) LTD Computed By: S A Karunaratne159, Model Farm Road, Colombo 08 Date: 2006-11-24

Analysis of 36 No. cube test results furnished by SUPERMIX to Singapore Piling

for Grade 35 concrete to be used for concreting in Luxary Apartment Building at Lot A1 & B3, Galle Road, Colombo 03.

(Analysis carried out in place of trial batching to verify the "Mix Design")Result

No Date Cast Date Tested Age Days N/mm2

at test fi fi - fm (fi - fm)2

1 1-9-06 29-9-06 28 34.5 -6.60 43.522 1-9-06 29-9-06 28 40 -1.10 1.203 1-9-06 29-9-06 28 41 -0.10 0.014 31-8-06 28-9-06 28 47.5 6.40 41.005 31-8-06 28-9-06 28 42 0.90 0.826 31-8-06 28-9-06 28 41.5 0.40 0.167 30-8-06 27-9-06 28 35.5 -5.60 31.338 30-8-06 27-9-06 28 39 -2.10 4.409 30-8-06 27-9-06 28 37.5 -3.60 12.9410 14-8-06 11-9-06 28 36.5 -4.60 21.1311 14-8-06 11-9-06 28 38 -3.10 9.5912 14-8-06 11-9-06 28 39 -2.10 4.4013 13-8-06 10-9-06 28 43 1.90 3.6214 13-8-06 10-9-06 28 42.5 1.40 1.9715 13-8-06 10-9-06 28 40 -1.10 1.2016 8-8-06 5-9-06 28 37.5 -3.60 12.9417 8-8-06 5-9-06 28 39.5 -1.60 2.5518 8-8-06 5-9-06 28 35.5 -5.60 31.3319 30-7-06 28-8-06 29 47 5.90 34.8420 30-7-06 28-8-06 29 41.5 0.40 0.1621 30-7-06 28-8-06 29 46 4.90 24.0422 27-7-06 24-8-06 28 43 1.90 3.6223 27-7-06 24-8-06 28 44 2.90 8.4324 27-7-06 24-8-06 28 43.5 2.40 5.7725 23-7-06 21-8-06 29 41.5 0.40 0.1626 23-7-06 21-8-06 29 46 4.90 24.0427 23-7-06 21-8-06 29 41.5 0.40 0.1628 22-7-06 21-8-06 30 41.5 0.40 0.1629 22-7-06 21-8-06 30 41.5 0.40 0.1630 22-7-06 21-8-06 30 42 0.90 0.8231 30-6-06 28-7-06 28 44 2.90 8.4332 30-6-06 28-7-06 28 35.5 -5.60 31.3333 30-6-06 28-7-06 28 45 3.90 15.2334 29-6-06 23-8-06 55 39.5 -1.60 2.5535 29-6-06 23-8-06 55 41 -0.10 0.0136 29-6-06 23-8-06 55 45.5 4.40 19.3837 0.00 0.0038 0.00 0.0039 0.00 0.0040 0.00 0.00

36Total = 1479.5 403.41

Average = Total /36 fm = 41.10s = (fi - fm2/ 36 3.35

1.64 s = 5.49Therefore fcu = fm - 1.64s = 35.61 N/mm2 > 35N/mm2

Note: Concrete Cube results are acceptableHowever, No. of cube results less than 40 and Contractor is responsible

Analysis of recently cast concrete test cube results in place of mix design trial mix tests

19

A6 B6

C6D6

AB BABC

CBCDDCDAAD

150 Cast Cube mould markings

Casting concrete cylinders & cubes for tests(i) Place concrete in three layers

(ii) Compact each layer 35 blows; 350mm long

16mm rod or 25mm2 area bar (600mm bullet nosed rod)

150 x 300 CAST MOULD

STEMS Project 35 Storey Tower, Lot A1 & B3, Colombo 03STEMS CONSULTANTS (PTE) LTD Computed By: S A Karunaratne159, Model Farm Road, Colombo 08 Date: 2007-08-18

Compressive Strength (28 Day Test Results) - To BS 5328: Part 4: 1990: Clause 3.16.2

Set Of Results No CC/02/239Specified Compressive Strength = 30 N/mm^2Number of Cube Results available= 3

Test Cube Result 1 = 45.5 N/mm^2 Condition (b) Satisfied 45.5 > 27 N/mm^2Test Cube Result 2 = 48 N/mm^2 Condition (b) Satisfied 48 > 27 N/mm^2Test Cube Result 3 = 50 N/mm^2 Condition (b) Satisfied 50 > 27 N/mm^2Test Cube Result 4 = 0 N/mm^2 Not Applicable

Average Results = 47.83 N/mm^2 Condition (a) Satisfied 47.83>=32 N/mm^2

Therefore Concrete Cube Results is OKAY


Test Cube Result 1 = 34.5 N/mm^2 Condition (b) Satisfied 34.5 > 27 N/mm^2Test Cube Result 2 = 29.5 N/mm^2 Condition (b) Satisfied 29.5 > 27 N/mm^2Test Cube Result 3 = 0 N/mm^2 Not ApplicableTest Cube Result 4 = 0 N/mm^2 Not Applicable

Average Results = 32 N/mm^2 Condition (a) Satisfied 32>=31 N/mm^2



Test Cube Result 1 = 49.5 N/mm^2 Condition (b) Satisfied 49.5 > 27 N/mm^2Test Cube Result 2 = 47.5 N/mm^2 Condition (b) Satisfied 47.5 > 27 N/mm^2Test Cube Result 3 = 46.5 N/mm^2 Condition (b) Satisfied 46.5 > 27 N/mm^2Test Cube Result 4 = 0 N/mm^2 Not Applicable



Set Of Results No 0Specified Compressive Strength = 30 N/mm^2Number of Cube Results available= 4

Test Cube Result 1 = 30 N/mm^2 Condition (b) Satisfied 30 > 27 N/mm^2Test Cube Result 2 = 50 N/mm^2 Condition (b) Satisfied 50 > 27 N/mm^2Test Cube Result 3 = 34 N/mm^2 Condition (b) Satisfied 34 > 27 N/mm^2Test Cube Result 4 = 29 N/mm^2 Condition (b) Satisfied 29 > 27 N/mm^2


a. Concrete test cube compliance

20

D. Concrete

Type of concreteType of concrete Max. total % Max. total % of chloride ion of chloride ion by mass of by mass of combined combined aggregateaggregate

Max. total % of Max. total % of chloride ion by chloride ion by mass of mass of cementcement

PrestressedPrestressedconcreteconcreteR/C with cement to R/C with cement to BS 12BS 12R/C with cement to R/C with cement to BS 4027 & BS 4248BS 4027 & BS 4248

0.100.100.010.01

0.050.05 0.400.40

0.030.03 0.200.20

Chloride in fine aggregate & in concrete

21

Maximum shell content in offshore sand

SizeSizeLimit on shell Limit on shell content (%)content (%)

Fractions of single size or of graded or Fractions of single size or of graded or allall--in aggregate, coarser than 10mmin aggregate, coarser than 10mm 88

Fractions of 10mm single size, or of Fractions of 10mm single size, or of graded or allgraded or all--in aggregate finer than in aggregate finer than 10mm & coarser than 5mm10mm & coarser than 5mm

2020

Aggregate finer than 5mmAggregate finer than 5mm No No requirementrequirement

GRADES GRADES C C

AveraAvera 4 4 ResultsResults



BS & {ICTAD} BS & {ICTAD} IndiviIndivi. Result > . Result >

C8/10C8/10 12(2)12(2) 11(1)11(1) 10(0)10(0) 8(2) ; {8(2)}8(2) ; {8(2)}

C12/15C12/15 17(2)17(2) 16(1)16(1) 15(0)15(0) 13(2) ; {13(2)}13(2) ; {13(2)}

C16/20C16/20 23(3)23(3) 22(2)22(2) 21(1)21(1) 17(3) ; 17(3) ; {18(2)}{18(2)}

C20/25C20/25 28(3)28(3) 27(2)27(2) 26(1)26(1) 22(3) ; 22(3) ; {23(2)}{23(2)}

C25/30C25/30 33(3)33(3) 32(2)32(2) 31(1)31(1) 27(3)27(3)

C28/35C28/35 38(3)38(3) 37(2)37(2) 36(1)36(1) 32(3)32(3)

C32/40C32/40 43(3)43(3) 42(2)42(2) 41(1)41(1) 37(3)37(3)

C40/50C40/50 53(3)53(3) 52(2)52(2) 51(1)51(1) 47(3)47(3)

Compliance criteria of concrete cube test results

Cast 6 cubes; Test 01 at 07 days (0.75 of 28 days strength) ; Test 04 at 28 days

(b) Lowest individual strength of any cube > 0.85 of characteristic strength

The difference of strength of two specimens < 15% of mean strength

(a) Average of 3 cubes >=characteristic strength

Two test specimens form a single result for compliance with the above chart

(Max Mini) of 3 results < 20% of average of 3 results

For small projects -ICTAD

22

What is C35A concrete

Grade 35 concrete for structures retaining Aqueous (Water like) - (suffix - A) liquids

Maximum cement content 400 kg/m3

Minimum cement content 325 kg/m3

Maximum free water cement ratio 0.55(Water reducing agents could be used)

Aggregates Maximum water absorption

23

READY MIXED CONCRETECentral MixedCentral Mixed Transit MixedTransit MixedAggregate added at speed Aggregate added at speed 10 to 18 rpm up to 100 10 to 18 rpm up to 100 revolutionsrevolutions

Materials are batched in a Materials are batched in a central plant central plant no addition no addition of waterof water

Transport Agitator Truck 2 Transport Agitator Truck 2 to 6 rpmto 6 rpm

Mixing in transit or at Mixing in transit or at discharge speed 4 to 16 discharge speed 4 to 16 rpm of truck mixerrpm of truck mixer

For uniformity of mixing For uniformity of mixing limit to 300 revolutionslimit to 300 revolutions

For uniformity of mixing For uniformity of mixing limit to 300 revolutionslimit to 300 revolutionsCement balls up to 200mm Cement balls up to 200mm if no proper controlsif no proper controls

The speed of mixing affects the rate of stiffeningThe speed of mixing affects the rate of stiffening

Basic Requirements for Basic Requirements for Placing Concrete (1)Placing Concrete (1)

Preserve concrete qualityPreserve concrete quality WaterWater--cement ratiocement ratio SlumpSlump HomogeneityHomogeneity

Avoid separation of aggregate and Avoid separation of aggregate and mortarmortar

24

Basic Requirements for Basic Requirements for Placing Concrete (2)Placing Concrete (2)

Avoid excessive horizontal movementAvoid excessive horizontal movementConsolidate adequatelyConsolidate adequatelyMaintain sufficient placement capacityMaintain sufficient placement capacityChoose the right equipment for the concreteChoose the right equipment for the concrete

Depositing ConcreteDepositing Concrete

Start placing along perimeter at one end Start placing along perimeter at one end with each batch discharged against with each batch discharged against previously placed concretepreviously placed concrete

Do not Do not (a) dump in separate piles & then (a) dump in separate piles & then

level and work togetherlevel and work together(b)(b) deposit in large piles & then deposit in large piles & then move move horizontally into positionhorizontally into position

These practices result in segregationThese practices result in segregation(mortar flows ahead of coarser material)(mortar flows ahead of coarser material)

Slab Construction

25

Incorrect Placement with Incorrect Placement with Conveyor BeltConveyor Belt

Baffle

MortarRock

Mortar

MortarRock

Shallow hopper

Placement with Placement with Conveyor BeltConveyor Belt

Belt Scraper

No Separation

Provide at least 0.6 m (24 in.) headroom for downpipe, elephant trunk or equivalent

26

Depositing ConcreteDepositing Concrete Deposit in horizontal layers of Deposit in horizontal layers of

uniform thicknessuniform thickness Reinforced Reinforced 150 mm to 500 mm150 mm to 500 mm Mass Mass 375 mm to 500 mm375 mm to 500 mm

Consolidate each layer before Consolidate each layer before next is placednext is placed

Timely placement & Timely placement & consolidation prevents flow linesconsolidation prevents flow linesand cold jointsand cold joints

Walls

Placing Concrete Placing Concrete in pilesin piles

Used: Tremie

Advantages: Can be used to funnel concrete down through the water / bentonite into the structure.

Watch for: Discharge end always has to be buried in fresh concrete to ensure seal between water and concrete mass.

27

Consolidating Consolidating ConcreteConcrete

Internal VibrationInternal Vibration

External VibrationExternal Vibration

Internal VibrationInternal Vibration

d

R

1 R

Vibrator

Radius of Action

28

Internal VibratorsInternal Vibrators of of head,head,mmmm

frequency, frequency, vibrations vibrations per minuteper minute

radius of radius of action, action,

mmmm

Rate of Rate of placemenplacemen

t,mt,m33/h/h ApplicationApplication

2020--4040 90009000--15,00015,000 8080--150150 0.80.8--44

3030--6060 85008500--12,50012,500 130130--250250 2.32.3--88

5050--909080008000--12,00012,000

180180--360360 4.64.6--1515 Stiff plastic Stiff plastic concrete (less than concrete (less than

8080--mm slump) mm slump)

Plastic concrete in Plastic concrete in thin walls, thin walls,

columns, beams, columns, beams, precast piles, thin precast piles, thin

slabs, slabs,

Plastic and flowing Plastic and flowing concrete in thin concrete in thin members. Also members. Also

used for lab test used for lab test specimens.specimens.

Systematic Vibration of Systematic Vibration of Each New LiftEach New LiftCORRECTCORRECTVertical penetration a few inches into previous lift (which should not yet be rigid) of systematic regular intervals will give adequate consolidation

INCORRECTINCORRECTHaphazard random penetration of the vibrator at all angles and spacingswithout sufficient depth will not assure intimate combination of the two layers

29

Placing Concrete in a Placing Concrete in a Sloping LiftSloping Lift

CORRECTCORRECTStart placing at bottom of slope so that compaction is increased by weight of newly added concrete. Vibration consolidates the concrete.

INCORRECTINCORRECTWhen placing is begun at top of slope the upper concrete tends to pull apart especially when vibrated below as this starts flow and removes from concrete above.

External VibrationExternal Vibration

Form vibratorsForm vibratorsVibrating tablesVibrating tablesSurface vibratorsSurface vibrators Vibratory hand floats or trowelsVibratory hand floats or trowels

30

Floating (Power or Hand)Floating (Power or Hand) To embed aggregate To embed aggregate

particles just beneath the particles just beneath the surface surface

To remove slight To remove slight imperfections, humps, and imperfections, humps, and voidsvoids

To compact the mortar at To compact the mortar at the surface in preparation the surface in preparation for additional finishing for additional finishing operations. operations.

TrowelingTroweling Creates smooth, Creates smooth,

hard,dense surfacehard,dense surface Exterior concrete should Exterior concrete should

not be not be troweledtroweled because: because: it can lead to a loss of it can lead to a loss of

entrained air caused by entrained air caused by overworking the surfaceoverworking the surface troweledtroweled surfaces can be surfaces can be

slippery when wet. slippery when wet.

31

Curing and ProtectionCuring and Protection

Cure for 7 daysCure for 7 days

Impervious CoverSprinkling of water

Curing Agent

Minimum period for curing Minimum period for curing & protection& protectionSurface concrete Surface concrete temperature temperature oo CC5 5 -- 1010 > 10> 10 2525

AverageAverage 4 Days 4 Days 3 Days 3 Days 2 Days 2 Days

PoorPoorAverageAverage

66 44 33All except All except (1) with (1) with ggbfsggbfs or or pfapfa

PoorPoor 1010 77 44

AllAll GoodGood No curingNo curing

(1) OPC, (1) OPC, RHPC, RHPC, SRPCSRPC

Type of Type of cementcement

Ambient Ambient conditions conditions after after concretingconcreting

Table 6.5 of BS 8110

32

Controlling temperatures in mass concrete

Volume > 300m3 & thickness > 600mm

i. Concrete temperature to 600 C maximum

ii. Temperature difference at center & surface to 200 C maximum

Limit

a. Temp > 710 C - internal expansion & cracking

b. Temp > 880 C - reduced compressive strength

Or minimum dimension > 1.8m

50kg cement temperature increase very approx. 4.290 C 7.140 C ; control with fly ash / ggbfs

Temperature rise in concrete above ambient Temperature rise in concrete above ambient surrounding surrounding in in 00 CC

Section Section thickness thickness (mm)(mm)

18mm plywood 18mm plywood (Steel)(Steel) formwork formwork cement content cement content -- kg/mkg/m3 3

220 290 360 400220 290 360 400

10 10 --1414 14 14 -- 1919 18 18 -- 2626 21 21 -- 3131

5 5 -- 77 7 7 -- 1010 9 9 -- 1313 10 10 -- 1515

9 9 -- 1313 13 13 -- 1717 16 16 -- 2323 19 19 -- 2727

13 13 -- 1717 18 18 -- 2424 23 23 -- 3333 27 27 -- 3939

18 18 -- 2323 24 24 -- 3232 33 33 -- 4343 39 39 -- 4949

15 15 -- 1919 20 20 -- 2727 27 27 -- 3636 31 31 -- 4343

18 18 -- 2323 25 25 -- 3232 34 34 -- 4343 40 40 -- 4949

22 22 -- 2727 31 31 -- 3737 42 42 -- 4848 47 47 -- 5656> 1000> 1000

700700

500500

< 300< 300

33

150mm sand layer or felt

25mm polystyrene or

Shear R/F

Main R/F

polythene layer

Additional R/F mesh

Formwork

First concrete pour

Balance concrete to be poured

Surface Insulation Arrangement (warm the surface & reduce temp difference

Working Safely with ConcreteWorking Safely with ConcreteProtect:Protect:

Your EyesYour Eyes

Your BackYour Back

Your SkinYour Skin

34

E. Detailing

COVER & SPACERS FOR REINFORCED CONCRETE

35

Cover to R/FoCover to R C Member is the minimum thickness of concrete over the R/F steelmeasured from exposed surface to the closest reinforced steel surface.

oCover is subjected to ingress of moisturealong with other chemicals, impact & wear

oCover should be dense having low permeability, durable, strong, free from honeycombs, cracks, voids & should be wear resistant

Cover to R/Fo Cover protects R/F steel from corrosion

o Cover ensures R/F bond to concrete to developits strength

o Spacers ensure location of R/F at the right location

o Incorrect R/F placement can lead even to failureso For eg. lowering top R/f or raising bottom R/F by 12mm in a 150mm slab, load carrying capacity could reduce by 20%

36

LocationLocation Minimum coverMinimum cover

Concrete in contact Concrete in contact with groundwith ground

75mm75mm

-- Do with formworkDo with formwork 50mm50mmColumnsColumns Main Main 40mm, links 40mm, links 25mm25mmWallsWalls 25mm & > 25mm & > of barof barBeamsBeams 35mm & > 35mm & > of bar, Links of bar, Links --

20mm20mmSlabsSlabs 20mm20mmEnd of barsEnd of bars 25mm & > 2 25mm & > 2 of barof barAt the foot of chairsAt the foot of chairs > Cover to main bars of member> Cover to main bars of member

Minimum cover to reinforcement

Extensively corroded slab and beam

37

Devices used to provide coveroStone chips get dislodged, & undesirable

oWood spacers inexpensive, difficult toremove & undesirable

o Cement mortar cover blocks inexpensive,porous, full of voids and allow moisturepenetration & undesirable

o Concrete cover blocks, Plastic spacers & Metal spacers costly, produced withquality & desirable

SPACERS

SPACERSSpacers are components which providecover (between 15 to 100mmin increments of 5mm,) between reinforcement and formwork or blinding.

Two main groups of spacers are: Clip-on typeWire-on type attach to bar by tying wire

38

Cementitious spacers

The mix used for spacer blocks should becomparable in strength , durability, porosity and appearance to the surrounding concrete.

Concrete spacers made at site must not be used according to BS 8110. How practical in Sri Lanka?

Making 75mm concrete cover blocks

39

t = nominal cover

t

Concrete cover blocksSeat min. =St2 + 75mm

Upstand height =h - ct - cb - t1 - t2 - b1 - b2

Leg length min.Sb2 + 75mm

Re - bar chair

Shape of traditional spacers

Concrete cover blocks and re-bar chairs

40

PLASTIC CHAIRS

41

Tying wire

16 gauge black annealed wire. Corrosion resistant wire of equal strengthmay be used.

Projecting ends of tying wire should not encroach into concrete cover.

No need to tie at every intersection

SLABS

Perimeter bars tied at every intersection

Bars up to 20mm tie at alternate intersections

Greater centres for R/F 25mm & above but notexceeding 50 of the smallest bar.

TYING OF BARS

SPACERS FOR SLABS continued

42

Section Section

Key Plan view of spacer Side view of spacer nominal size of bar

nearest to surface

500mm max

50 , but

43

Spacers on alternate bars

Section Elevation

a) Without horizontal R/F

Spacers at 50 or at a maximumof 1000mm centres

Section Elevation

b) With horizontal R/FKey Plan & side view of spacer

Wire tie

Spacers for slab edges

Spacers in a slab

44

BEAMS

TYING WITHIN BEAMS Every intersection of a corner of a link

with longitudinal bar should be tied.

Other bars within the links should be tied at 50D centres

SPACERS FOR BEAMS continued

Every bar endshould have asuitable spacer

1000mm max. Up to 250mm, one spacer

Beam elevation Narrow beam

Deep beam> 100

Spacers @ Spacers @ 50 max. 50

250 to 500mm Wide beam > 500mm two spacers

Spacers for sides of deep beams

Normal Deep beam Wide beambeam

Spacers for beams

45

Spacers in a deep beam

COLUMNSTYING WITHIN COLUMNS

Main vertical bars and links should betied at every intersection

Spacers for spiral links follow same rulesas for circular columns

SPACERS FOR COLUMNS continued

46

Spacers @50 maximum

All spacers fixed to links at top, middle Face

& bottom of each lift, < 50 not exceeding 100

Face > 50

Spacers along column Wide columnFaces less Spacers @ 50 maximumthan 50 At least four per group

One spacer per 50 ofbar for

each facet

Small column Multifaceted columns Circular column

Spacers for columns

WALLSTYING WITHIN WALLS

Follow guidelines given for slabs

Spacers on opposite faces should coincidewhen viewed in elevation

SPACERS FOR WALLS continued

47

Continuous chairs at a maximum of 1000mm centres

50 or 500mm

Spacers at a max. of 50 but not less than 500mm in both directions

Elevation SectionKey Plan & end view of spacer

Plan view of continuous chairSide view of continuous chair

End view of continuous chair

Plan Spacers for walls

Spacers in wall R/F

48

Earthquake effects mitigation detailing

- Dia. Of cross tie

Shape of stirrups & crossties

135 o

90 o 135 o

Stirrup or hoop Crosstie

Values given in ( ) are for mild steel reinforcement)

beam confinement zones and wall end zones

Stirrups & crossties for columns, beam-column joints

135 o

>=6 (10)>=80mm (100mm)

Dia >=5hoop

49

Actual shape of stirrup

Reinforcement in a wall

Wheel Spacer

Cross Tie

50

1350 hook

Column Vertical R/F arrangement

0.5l

ln/2

ln/2

for R/F lap

Structurallyln

for R/F lap

(a)

(b) = 3/4 of adjoining column width;is defined as confined joint

(a) > 50% R/F lapped

1.25l

51

Column Transverse R/F arrangement

X

At least 60% of transverse R/F provided in the

zone belowprovided in confinement

confinement zone below to be provided

Sc=50mm; =ln/6; >=500mm

o1 o2 o1

Link arrangement

at laps in columns

d = 2

b = 10

Double links at bends

Links at laps as in the

confinement zones

Crank detail

Column link arrangement at laps

52

FAILURE OF

COLUMNS

Beam longitudinal R/F arrangement

Wall

l

>= l>= 50

>= l >= l

ln

1/4 of max. support R/F

a

abb

(a+b)>=la>= 0.4 lb>=12

Bottom R/F of adjacentspan

Note: Do not provide bent-up bars

53

Beam Transverse R/F arrangement

combination ofstaggared with

closed links

Beam withclosed links

Side bars Crosstiesalternatively

= 2hk