IN SITU PILE TESTING PROCEDURE

The main objectives of the initial pile test are to verify the design capacity (compressive, tensile and lateral) of the pile before commencing installation of working piles and to evaluate the quality of pile installation works with TCVN 9393:2012 Piles – Standard test method in situ for piles under axial compressive, ASTM D1143: Standard Test Methods for Deep Foundation Under Static Axial Compressive Load.....

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A 08/12/2015 For approval

PROJECT:

SONG HAU 1 THERMAL POWER PLANT – TWO (2) X 600MW

SUB-CONTRACTOR

HANOI CONTRUCTION CORPORATION-JSC

Date Name Signature Document Title

Prepared 08/12/2015 N.Q.Khanh

IN-SITU PILE TESTING PROCEDURE

(Onshore)

Checked 08/12/2015 B.T.Son

Approved 08/12/2015 T.V.Dũng

Document No.: SH1-HNC-P0100-C-C14-PRO-0001 Rev.: A No of Pages: 11

FICHTNER GmbH & Co KG PV ENGINEERING

VIETNAM MACHINERY INSTALLATION

CORPORATION (LILAMA)

TOKYO ELECTRIC POWER SERVICES COMPANY LIMITED -TEPSCO VIETNAM OIL AND GAS GROUP (PVN)

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1 PROJECT INFORMATION 4

2 OBJECTIVE OF THE PILE TESTS 4

3 TESTING TYPES 4

4 REFERENCE DOCUMENTS 4

4.1 Codes and Standards 4

4.2 Project Specifications and Drawings 4

5 SUB-SOIL CONDITIONS 5

6 TEST PILE INFORMATION 5

7 TEST EQUIPMENT 5

8 TESTING UNIT 5

9 STATIC AXIAL COMPRESSIVE LOAD TEST 5

9.1 TEST PURPOSE 5

9.2 TEST METHOD 5

9.2.1 Applied Standard 5

9.2.2 Test Principle 5

9.2.3 Requirement for carrying out the static axial compressive load test 6

9.3 TESTING EQUIPMENT 6

9.3.1 Equipment for loading 6

9.3.2 Counter-Weight 6

9.3.3 Settlement Measuring Instruments 6

9.4 TESTING PROCEDURE 6

10 STATIC AXIAL TENSILE LOAD TEST 6

10.1 TEST PURPOSE 6

10.2 TEST METHOD 7

10.2.1 Technical Specifications 7

10.2.3 Requirement for carrying out the Static axial tensile load test 7

10.3 TEST EQUIPMENT 7

11 LATERAL LOAD TEST 7

11.1 TEST PURPOSE 7

11.2 TEST METHOD 7

11.2.2 Test Principle 8

11.2.3 Requirement for carrying out the Lateral Load Test 8

11.3 TEST EQUIPMENT 8

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12 LOW STRAIN IMPACT INTEGRITY TEST (PIT) 9

12.1 TEST PURPOSE 9

12.2 TEST METHOD 9

12.2.2 Test principle 9

12.4 TEST PROCEDURE 10

13 HIGH STRAIN DYNAMIC LOAD TEST (PDA) 10

13.1 TEST PURPOSE 10

13.2 TEST METHOD 10

13.2.2 Test principle 10

13.4 TEST PROCEDURE 11

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1 PROJECT INFORMATION

 Project: SONG HAU 1 THERMAL POWER PLANT - TWO (2) X 600MW

 Location: Mai Dam Town, Chau Thanh District, Hau Giang Province

 Investor: PETROVIETNAM

 EPC Construction: LILAMA JSC

 Sub Construction: HANCORP

2 OBJECTIVE OF THE PILE TESTS

The main objectives of the initial pile test are to verify the design capacity (compressive, tensile and lateral) of the pile before commencing installation of working piles and to evaluate the quality of pile installation works

3 TESTING TYPES

- Static Axial Compressive Load Test

- Static Axial Tensile Load Test

- Lateral Load Test

- High Strain Dynamic Load Test (PDA)

- Low Strain impact integrity Test (PIT)

4 REFERENCE DOCUMENTS

4.1 Codes and Standards

- TCVN 9393:2012 Piles – Standard test method in situ for piles under axial compressive

- ASTM D1143: Standard Test Methods for Deep Foundation Under Static Axial Compressive Load

- ASTM D3689: Standard Test Method for Deep Foundation Under Static Axial Tensile Load

- ASTM D3966: Standard Test Method for Deep Foundation Under Lateral Load

- ASTM D4945: Standard Test Method for High Strain Dynamic Testing of Deep Foundations

- ASTM D5882: Standard test method for Low strain impact integrity testing of deep foundation

4.2 Project Specifications and Drawings

Request for Proposal Owner’s Technical requirement, Technical specification for civil, structural and architectural works

5 SUB-SOIL CONDITIONS

The information of sub-soil profile is referred to “1st Soil Investigation Report” which was carried out on June, 2015

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After Soil Improvement Works finish and Post Soil Investigation carried out, the new soil condition should be considered in any piles calculation

6 TEST PILE INFORMATION

The test pile locations and numbers shall follow the technical requirement and be approved by the Owner/Consultant

The details construction of test pile shall be updated in followed documents

7 TEST EQUIPMENT

Testing equipment which shall be used for pile testing should meet the requiprements indicated from above mentioned Standards

8 TESTING UNIT

Testing unit should be the specialized registered LASXD in pile testing field The approved LASXD should provide site organization and the testing engineers should have qualified certificate which provide by authority organization

9 STATIC AXIAL COMPRESSIVE LOAD TEST

The Static Axial Compressive Load Test will be carried out for determination of compressive bearing capacity as the base for working piles design

9.2.1 Applied Standard

Loading test will be complied with Technical Specifications: ASTM D1143 and TCVN 9393:2012

9.2.2 Test Principle

The Static Axial Compressive Load Test shall be applied by static loading on axial direction for single pile so that the pile is settled down The testing load is controlled by hydraulic jack system with pressure gauges and counter-weight is created by a combination of steel beams and Jack-in pilling machine

Data of load, time and settlement obtained from the test shall be the basis for analyzing

of the relationship between load and settlement of pile and evaluation for pile compressive bearing capacity

9.2.3 Requirement for carrying out the static axial compressive load test

- The test piles must be constructed in the same method and procedure applied for all piles

in the stage of mass construction

- Top elevation of pile head shall be higher than the ground about 15cm

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- The test shall be only commenced at least 07 days after finishing installation of the pile.

9.3.1 Equipment for loading

Using hydraulic jacks with sufficient capacity connecting with hydraulic pump and pressure gauge, put directly on the top of test pile to create a load on pile’s centre

9.3.2 Counter-Weight

The Counter – Weight is Jack-in Machine’s Self- weight and the steel blocks which are put over the Jack-in Machine The total weight of Jack-in machine and steel block should be more than 150% of maximum testing load

9.3.3 Settlement Measuring Instruments

The settlement of PHC test pile shall be monitored by 04 dial gauges with 0.01mm precision and maximum stroke of 50mm They shall be fixed with the reference beams of steel stacks L50x50x2mm with 3.0m length This beam shall be set independently to the testing system by fixing them into 2 steel bars L80mm in corners, these bars are embedded about 1.5 m into the ground, at adequate distance from the testing bored pile and cushions, in order to eliminate effects from displacement of piles and cushions on readings of the dial gauges

Note: All testing equipment, jacks, gauges, etc shall be furnished by the Testing Unit and certificated by an authority organization.

The test piles shall be tested upto 200% of design load Test load on piles shall be applied with the hydraulic jack using a 25% load increment until reaching the specified Test Load At each load increment the test load shall be maintained until the rate of displacement is not greater than 0.25 mm per hour, measured over a period of at least 15 minutes but not greater than 2 hours Upon reaching maximum testing load, the test load should be mantianed in 24 hours during which the displacement shall be less than 0.25mm for the last hours of the test Displacement observation shall be made following application of each load increment and recorded at intervals of ½ minutes, 1 minute, 2 minutes, 4 minutes, 8 minutes, 15 minutes, 30 minutes, 1 hour and each hour thereafter

10 STATIC AXIAL TENSILE LOAD TEST

10.1 TEST PURPOSE

The uplift load test will be carried out for determination of tensile bearing capacity of pile as the base for working piles design

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10.2 TEST METHOD

10.2.1 Technical Specifications

Tension load test will be complied with Technical Specifications: ASTM D3689: Standard Test Methods for Deep Foundation Under Static Axial Tensile Load;

The test is carried out by the application of an axial static tensile load to a pile so that the pile pulled up from the ground by mean of the hydraulic jack and counter force from Testing beam and supporting blocks

Data of tensile load, time and displacement obtained from the test shall be the basis for analyzing of relationship between tensile load and displacement and evaluation of pile tensile bearing capacity

10.2.3 Requirement for carrying out the Static axial tensile load test

- The test piles must be constructed in the same method and procedure applied for all piles in the stage of mass construction

- Top elevation of pile head shall be higher than the ground at least 30cm

- The static tensile load test shall be only commenced at least 07 days after finishing installation of the pile

10.3 TEST EQUIPMENT

The equipment which shall be used for Tensile load test should meet the requipments indicated in ASTM D3689 and also need to meet requirement which presented in Static Axial Compressive Load Test part

10.4 TESTING PROCEDURE

The test piles shall be tested upto 200% of design load The test load applying procedure following the same increment/decrement and requirements as statted for Static Axial Compressive Load Test The displacement observation and record keeping shall be same as stated for Static Axial Compressive Load Test

11 LATERAL LOAD TEST

The lateral load test will be carried out for determination of lateral bearing capacity of piles in order to verify the design capacity of the pile

Loading test will be complied with Technical Specifications: ASTM D3966: Standard Test Method for Deep Foundation Under Lateral Load;

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11.2.2 Test Principle

The test is carried out by the application of a lateral static load to a pile so that the pile is moved laterally The lateral load is controlled by means of a hydraulic jacks and pump acting against a counter force system which is built beside the pile

Data of load, time and pile’s head lateral displacement obtained from the test shall be the basis for analysing of the relationship between load and lateral displacement of pile and evaluation of pile/soil’s lateral bearing capacity

11.2.3 Requirement for carrying out the Lateral Load Test

The test piles must be constructed in the same method and procedure applied for all piles

in the stage of mass construction

Top elevation of pile head shall be higher than the ground at-least 30 cm

The static load test shall be only commenced at least 07 days after finishing installation

of the pile

11.3 TEST EQUIPMENT

The equipment which shall be used for Tensile load test should meet the requipments indicated in ASTM D3689 and also need to meet requirement which presented in Static Axial Compressive Load Test part

11.4 TESTING PROCEDURE

Proposed testing procedure is presented in Table 9

Load step

0

5 Maintained in 10 minutes, checking

equipments

100 Maintained in 20 minutes

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Load step

During loading and unloading, the readings of time, load and displacement of pile head shall be taken and recorded for every increment and decrement at 0, 5, 10, 15, 20, 30, 45, 60 min

12 LOW STRAIN IMPACT INTEGRITY TEST (PIT)

The Low Strain Impact Integrity Test (PIT) will be carry out to evaluate the integrity of pile (change in pile physical dimensions (cross-sectional area, length), continuity, and consistency of the pile material

The PIT test shall be carry out according to ASTM D5882: Standard test method for Low strain impact integrity testing of deep foundation;

12.2.2 Test principle

Pile Integrity Test performs the wave equation-based non-destructive test known as Pulse

or Sonic Echo Test, or Low Strain Dynamic Test

Low strain impact integrity testing provides acceleration or velocity data on slender structural elements (that is, structural columns, driven concrete piles, bored piles, concrete filled steel pipe piles, timber piles, etc.) The method works best on solid concrete sections, and has limited application to unfilled steel pipe piles, H piles, or steel sheet piles

The test requires the impact of a small handheld hammer on the pile top and the measurement of the pile top motion (acceleration or velocity) The input compression wave from the hammer is reflected from pile toe (or a change in cross sectional area or pile material quality) and returns to the pile top at a time related to the wave speed which travel in the pile material

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12.3 TESTING EQUIPMENT

The PIT tests will be carried out with the Pile Integrity Tester PIT-V manufactured by Pile Dynamics, Inc The instrument complies with ASTM D5882 and at least has the following parameters:

- One channels of acceleration data acquisition for measuring acceleration, velocity due to the impact of the hand held hammer to the pile top

- 24 bit A/D converter;

- Analog Signal Frequency response: 31kHz (-3dB)

- Sampling Digitizing frequency of >1 MHz

- Sampling speed of 64 kHz for normal pile testing (up to 128 KHz for shorter piles or floor slabs)

- Capability of measuring and reproducing signals of duration between 8 and 30 ms

- Data can be averaged over a variable number of blows

- Variable signal amplification over time

12.4 TEST PROCEDURE

The test is carried out as follows:

- Input information of test pile (pile name, diameter, pile length etc.)

- Fix the accelerator on the center of fixing position

- Tapping on the pile head near accelerator by the hammer with at least 3 numbers of hammering for each location

13 HIGH STRAIN DYNAMIC LOAD TEST (PDA)

The High Strain Dynamic Load Test (PDA) will be carry out to confirm the bearing capacity and the integrity of PHC pile also

The PDA test shall be carry out according to - ASTM D4945-12: Standard Test Method

for High Strain Dynamic Testing of Deep Foundations;

13.2.2 Test principle

PDA is performed by utilizing the one dimensional wave theory The compressive stress wave produced by the impact of the falling weight moves up and down the pile When the wave encounters soil resistance forces along the shaft or at the toe it assumes an opposite direction (a refection) These reflections travel upward along the shaft and arrive at the pile top at times that are related to their location along the shaft Base on measuring of stress wave during testing, the subsequent parameter such as pile capacity, load distribuition will be drawn

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13.3 TESTING EQUIPMENT

The testing equipment complies with the specifications as defines in ASTM D4945 The primary testing equipment is a free drop hammer with a minimum weight of 1% to 2% of the pile’s test load (TL) (ASTM D4945) To setting up the testing hammer and carry out the test, the suitable crane shall be used

The secondary testing equipment consists of an Pile Driving Analyser which enables the collection of at least two sets of data for acceleration and strain at the same time

13.4 TEST PROCEDURE

* At site

Free dropping the hammer to impact on the pile head The sensors will receive the signals and transmit to the recorder and to the PAK for display PDA operator must always check the accuracy of the data and the homogeneity and balance during the test

* Indoor

Base on the site records, the Engineer will use the analysis software to evaluate the bearing capacity of pile CAWAP is the software analysis program that use the results of dynamic load test to the calculate the static load bearing capacity on pile (also side resistance and peak resistance), elastic modulus and soil viscosity, setting the relationship line between settlement and force of the pile

CAPWAP program uses the results of actual measurement as the input for the analysis, typical factors of soil and pile are calculated during the rebuilt of theoretic model in accordance to the measurement results

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