Omthesis 30-4-2016

PILE LOAD CAPACITY USING STATIC AND DYNAMIC LOAD TEST

Presented by:

ANUP KUMAR HALDERST NO-1009042218(P)

Program: M.Sc. Engineering (Geotechnical)

Supervisor:Dr Mehedi Ahmed Ansary

Date: 30th April 2016.

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OUTLINE

1. OBJECTIVE OF THE STUDY2. OVERALL METHODOLOGY3. LITERATURE REVIEW4. FIELD INVESTIGATION5. SAMPLE CALCULATIONS6. DATA COLLECTIONS7. CORRELATIONS AMONG DIFFERENT ESTIMATION METHODS8. CONCLUSIONS 9. RECOMMENDATIONS

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OBJECTIVE OF THE STUDY

To determine the ultimate compressive pile load capacity of precast driven pile using Pile Dynamic Analyzer.

To determine the ultimate compressive pile load capacity of precast pile using SPT value and pile driving records.

To determine the ultimate compressive pile capacity using Static Pile load test.

To compare the pile load capacity obtained from different methods.

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2. OVERALL METHODOLOGY

ESTIMATION OF PILE CAPACITY

SOIL INVESTIGATION REPORT

DRIVING EQUATION

DYNAMIC LOAD TEST

STATIC LOAD TEST

1. BNBC-20152. AASHTO-1992

1.ENGINEERING NEWS2.GATES FORMULA3.JANBU FORMULA

CAPWAP 1. DAVISSION METHOD

2. BNBC-933. OTHERS

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3. LITERATURE REVIEW

for clays with for clays with

PILE CAPACITY

DRIVEN PILE CAPACITY

NON-COHESIVE SOIL(β-METHOD)

COHESIVE SOIL(α-METHOD)

STATIC FORMULA

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Sand Non-plastic silt Sand Non-plastic silt

PILE CAPACITY

DRIVEN PILE CAPACITY

NON-COHESIVE SOIL

COHESIVE SOIL USING SPT

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=Undrained shear strength Bearing capacity factor = Friction due to overburden

= Effective vertical stress

PILE CAPACITY

BORED PILE/DRILLED SHAFT CAPACITY

NON-COHESIVE SOIL

COHESIVE SOIL STATIC

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Sand Non-plastic silt Sand Non-plastic silt

PILE CAPACITY

BORED PILE CAPACITY

NON-COHESIVE SOIL

COHESIVE SOIL USING SPT

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PILE CAPACITY

BORED PILE CAPACITY

NON-COHESIVE SOIL

COHESIVE SOIL AASHTO 1992

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H=height of fall of rams=amount of penetration per blow.

a=104.5e=Point penetration per blowb=2.4

=

s=Pile set

PILE CAPACITY

PRECAST PILE

JANBU FORMULAENGINEERING NEWS

DRIVING EQUATIONS

GATES FORMULA

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1. CONSTANT RATE OF PENETRATION (CRP)

2. MAINTAINED LOAD TEST (ML)EVALUATION METHOD3. DAVISSION4. BS 80045. IS: 29116. BUTLER-HOY7. BRINCH-HANSEN 90%

CRITERION

PILE CAPACITY

LOAD TEST

STATIC(ASTM D1143)

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3. LITERATURE REVIEWPILE CAPACITY

DYNAMIC LOAD TEST

ASTM D4945-00Force applied=PArea=ALength=LElement length=dlMovement of point X=dd (deformation)Wave speed, c=dl/dtDeformation, dd= P dl/EAParticle velocity, dv=dd/dt=P dl/EAdt=Pc/EAAcceleration of the point, a=dv/dt =Pc/EA dtNewton’s second law, P=mam=dl(A)ρP=dlAρ(Pc/EA dt)Wave speed, c²=E/ρ

P

L

dl

dd

Point, X

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3. LITERATURE REVIEW (Dynamic load test)

Wave propagation in a pile (Cheney and Chassie, 1993)

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3. LITERATURE REVIEW (dynamic load test)

STRAIN TRANSDUCERF(t)=EAε(t)E=Elastic modulusA=Cross sectionε=Strain

ACCLEROMETERV(t)=∫a(t)dt

Setting arrangement of strain transducer and accelerometer

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Force(+) for Compression Force(-) for Tension

Velocity(+) for Downward Velocity(-) for Upward

Free End Wave Mechanics

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Fixed End Wave Mechanics

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The displacement at which the soil changes from elastic to plastic behavior is referred to as the soil “quake”.

Typical wave equation model

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3. LITERATURE REVIEW (dynamic load test CAPWAP method)

Factor Influence CAPWAP matching (after Hannigan, 1990)

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4. FIELD INVESTIGATION (soil investigation) cont…

PILE TYPE : PRECASTSECTION: 12”x12”(300mmX300mm)LENGTH: 13.7m

PRECAST PILE AT SITE

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4. FIELD INVESTIGATION (dynamic test) cont…

TEST PILE-1 TEST PILE-2

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4. FIELD INVESTIGATION (dynamic test) cont…

PILE DRIVING ANALYZER

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4. FIELD INVESTIGATION (static test) cont…

Design Load 40 Ton

Target test load 2.5XDesign load=100

Ton

Type of pile Reinforced concrete pre-

cast pile

Dimension 300mmX300mm

(12”X12”)

Method of installation Impact hammering

Driving equipment Skid mounted pile driver

Hammer detail Drop hammer

Static Load Test Plan

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5. SAMPLE CALCULATION (capacity calculation)

PILE TYPE : PRECASTSECTION: 12”x12”(300mmX300mm)LENGTH: 13.7mMETHOD: BNBC 2015 (STATIC FORMULA)

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5. SAMPLE CALCULATION (capacity calculation)

cont…

• PILE TYPE : PRECAST• SECTION: 12”x12”(300mmX300mm)• LENGTH: 13.7m• METHOD: BNBC 2015 (SPT BASED)

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5. SAMPLE CALCULATION (capacity calculation) cont…

ENGINEERING NEWS FORMULA

Weight of ram,

Number of blows for last one feet of penetration=40

Penetration of pile under last blow of hammer, s=0.3 in

Height of fall of ram, H=5 ft

Resistance under working load,

R

=13.46 kN FS=6

Ultimate Capacity=804 kN

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5. SAMPLE CALCULATION (capacity calculation) cont…Pile area, A =144 sq in

Length of pile, L =45 FtWeight of pile, Wp =6.75 kip

Compressive strength of concrete =3500 psiModulus of elasticity of concrete, Ec = 57500√3500

=3401746 psi =3402 ksi

AE =489851kipcd 0.75+0.15(Wp/Wr)

=0.75For drop hammer, eh =0.75

Height of fall =5.00 ftEh =35.00 ft-lb

S =0.30

=3.86

2.61=

=1790 kN (FS=4.5)

JANBU FORMULA

DRIVING OF PILE

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5. SAMPLE CALCULATION (capacity calculation) cont…

Hammer weight =7 kipDrop of hammer =5 ft

,Eh =35 kip-ft ,eh =0.75

Point penetration per blow, s =0.3 in/blow

=210 kip = 1049 kN

GATES FORMULA

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5. STATIC LOAD TEST (PRECAST)

Load settlement graph for Pile load test TP-1

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5. STATIC LOAD TEST (PRECAST)

Load settlement graph for Pile load test TP-2

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5. SUMMARY FOR STATIC LOAD TEST (PRECAST)

Pile ID Capacity kg(kN)

Davission Offset

BS 8004 IS: 2911 Butler and Hoy Brinch Hansen

TP-1 Out of range Out of range Out of range Out of range Out of rangeTP-2 81 Ton

(807 kN)

88.5 Ton

(881 kN)

78 Ton

(777 kN)

79 Ton

(787 kN)

+90 Ton

(896 kN)

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5. SUMMARY OF PLILE CAPACITY (PRECAST)

Formulas used Total resistance

TP-1(kN)

Total resistance

TP-2(kN)Engineering News 804 792Janbu 1790 1733

Gates 1049 1026

CAPWAP(Dynamic) 1213 500

Static (Average) 1000 830

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5. DATA COLLECTION (CAPWAP Analysis PRECAST TP-1 & TP-2)

TIME OF IMPACT

TOE REFLECTION

LARGE SEPARATION BETWEEN FORCE AND VELOCITY INDICATE A LARGE SHAFT RESISTANCE

CONVERGENCE BETWEEN FORCE AND VELOCITY RECORDS BEFORE 2L/C INDICATE SLIGHT PILE DAMAGE

BETA FACTOR=100%

BETA FACTOR=73%

2L/C

2L/C

CAPWAP TP-1

CAPWAP TP-2

Beta Pile Condition

100% OK

60% -80%

Slightly damage

≤60% Damage

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6. DATA COLLECTION FROM OTHER SOURCES (PRECAST)

SL No Site Pile length

(m)

Pile section(mXm)

Pile IDBNBC Static Bearing (KN)

BNBC SPT Value (KN)

CAPWAP Capacity (KN)

1 PABA_NUR 21.34 0.3mX0.3m P-26(H-07) 750 932 9912 PABA_NUR 21.34 0.3mX0.3m P-04(G-07) 1781 1510 17563 MANIK 13.72 0.3mX0.3m PC-4 P-4 854 894 822

4 MANIK 13.72 0.3mX0.3mPC-8B P-134 854 881 788

5 MANIK 13.72 0.3mX0.3m PC-5 P-67 1054 749 11586 MANIK 13.72 0.3mX0.3m PC-4 P-218 1085 1199 654

7 SHARIAT 16.16 0.35mX0.35m TP-02 776 1241 846

8 SHARIAT 16.16 0.35mX0.35m TP-04 924 1242 8799 TANGAIL 13.72 0.3mX0.3m P-24 849 1224 1214

10 TANGAIL 13.72 0.3mX0.3m P-141 848 1281 50011 Keranigonj 12 0.3mX0.3m TP-2 1125 1378 90512 COXBAZAR 13.5 0.3mX0.3m TP-2 1032 1452 140213 COXBAZAR 13.5 0.3mX0.3m TP-3 1336 994 1192

14 COXBAZAR 13.5 0.3mX0.3m TP-5 1336 1083 1644

15 Borguna 16.7 0.35mX0.35m P-106 1330 1332 1128

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6. DATA COLLECTION FROM OTHER SOURCES (CAST-IN-SITU)

SL Location

Pile Data Pile capacity (KN)

Dia(m)

Length(m) BNBC-2015

SPT

BNBC-2015 Static bearing CAPWAP AASHTO

1 Basundhara_walton 0.5 28.5 1819 1807 2118 2363

2Titas Railway bridge_comilla 1.2 30.8 6719 5941 5000 6508

3Padma bridge Service area_Naodoba 1.2 29.5 5971 6380 3520 5963

4 Fly_over_Mogbazar 1.2 29.5 7201 5818 5043 77925 Fly_P114_Mogbazar 1.5 44.4 11176 11801 10374 123506 Fly_P180_Mogbazar 1.2 44 9303 7785 7221 9715

7BRRL_P1_Road Research lab 1 22.5 2965 2847 2196 3821

8BRRL_P2_Road Research lab 1 28 4743 2615 4589 4229

9LRP_P3 bridge pier Zinzira_dohar road 1 23.7 4768 4375 3635 4287

10LRP_P4 bridge pier Zinzira_dohar road 1.2 24 5862 3231 3408 4412

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5. DATA COLLECTION (CAST-IN-SITU)

BRRL_P1_Road Research lab BRRL_P2_Road Research lab

LRP_P3 bridge pier Zinzira_dohar road LRP_P4 bridge pier Zinzira_dohar road

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7.CORRELATIONS AMONG DIFFERENT ESTIMATION METHODS (PRECAST PILES)

600 800 1000 1200 1400 1600 1800 20000

500

1000

1500

2000

f(x) = 0.879883119535237 x + 123.939630594493R² = 0.506338922471201

CAPWAP capacity (kN)

Stati

c Be

arin

g ca

paci

ty B

NBC

-201

5 (k

N)

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700 800 900 1000 1100 1200 1300 1400 1500 16000

500

1000

1500

2000

f(x) = 0.365692528808019 x + 634.473968665097R² = 0.0562779857911625


BNBC

201

5 SP

T Ca

paci

ty 9

kN)

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600 800 1000 1200 1400 1600 1800 20000

500

1000

1500

2000

f(x) = 0.313620507819001 x + 826.351062724575R² = 0.152860008202632

Static Bearing capacity BNBC-2015 (kN)

BNBC

201

5 SP

T Ca

paci

ty (k

N)

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7.CORRELATIONS AMONG DIFFERENT ESTIMATION METHODS(BORED PILES)

0 2000 4000 6000 8000 100000

2000

4000

6000

8000

10000

f(x) = 0.864690125251404 xR² = 0.962302298547864

BNBC-2015 Static bearing capacity(kN)

CAPW

AP ca

paci

ty (k

N)

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7.CORRELATIONS AMONG DIFFERENT ESTIMATION METHODS (BORED PILES)

0 2000 4000 6000 8000 10000 120000

2000

4000

6000

8000

10000

12000

f(x) = 0.840653550924056 x − 377.617318544073R² = 0.877889792900387

BNBC-2015 SPT Capacity (kN)

CAPW

AP C

apac

ity (k

N)

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7.CORRELATIONS AMONG DIFFERENT ESTIMATION METHODS (BORED PILES)

1000 2000 3000 4000 5000 6000 7000 8000 9000 100000

2000

4000

6000

8000

10000f(x) = 1.27622937776803 xR² = 0.980520050175086


AASH

TO C

apac

ity (k

N)

8.CONCLUSIONS

1. In a mega project where pile number is huge it is very difficult to carry out the static load test frequently due to shortage of money or time. Application of dynamic test may be appropriate in those conditions.

2. Considering both soil test report and CAPWAP analysis co-relationships were established for precast and cast-in-situ piles. Further study is necessary in this regard to validate proposed equations of BNBC-2015.

3. During the study it was found that beta value is a very good indicator for pile integrity. This need to be utilized properly by our professionals.

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9.RECOMMENDATIONS

1. In this study, only the capacity of pile was estimated and compared but the effect of soil ‘set-up’ (change of soil strength and adhesion) was not considered. The effect of soil set-up need to be studied.

2. Proper selection of hammer or study is necessary for driving a pile without damaging it. This can be ensured by using PDA data of energy transfer ratio, pile stress and other indicator for optimize the appropriate diesel hammer.

3. Attention should be given to beta values from the PDA during driving and take necessary action to avoid damage.

4. There is no study for selection of damping factor and quake value for Bangladesh for CAPWAP analysis.

5. Though dynamic analysis is already use in our country there is no guideline in BNBC-2015. There should be a guideline along with standard to use it.

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Thank you allFor Patience Hearing

Omthesis 30-4-2016

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