Method Statement. Static Pile Load Test

Transcription

1 Method Statement FOR Static Pile Load Test (Compression Test,Tension Test and Lateral Test) PREPARED BY 1

2 METHOD STATEMENT FOR COMPRESSION, TENSILE AND LATERAL PILE LOAD TEST PROJECT INFORMATION Owner :.. Client :.. Main Contractor :. Contractor :. Location :. TEST PILE INFORMATION Pile No. 385 Pile No. 368 Pile No. 416 Pile Type 40 x 40 Driven 40 x 40 Driven 40 x 40 Driven Pile Tip 4.2 m. 4.2 m. 4.2 m. Pile Top 0.0 m. 0.0 m. 0.0 m. Design Load 65 tons 15 tons 7 tons Maximum Test Load (200 % of design 130 tons 30 tons 14 tons Load) Test Type Axial Compression Test Axial Tension Test Lateral Test Anchor Piles 367, 368, 416, , , 417, 385 Testing Standard ASTM D (Reapproved 1994) ASTM D (Reapproved 1995) ASTM D (Reapproved 1995) 2

3 1.0 TESTING APPARATUS 1.1 Reaction Beam The steel girders will be laid across the test pile with system set up similar to that shown in Appendix A. 1.2 Hydraulic Jacks Axial Compressive Test : One hydraulic jack (1x400) ton capacity will be provided on top of the pile head as loading apparatus. Axial Tension Test : One hydraulic jack (1x165) ton capacity will be provided on top of the pile head as loading apparatus. Lateral Test : One hydraulic jack (1x59) ton capacity will be provided on the side of the pile head as loading apparatus. 1.3 Ball Bearing To provide non-eccentric load to the pile head, a ball bearing shall be inserted in between the reaction beam and the hydraulic jack. 1.4 Dial gauges Four dial gauges (Mitutoyo brand) will be provided to monitor the pile movements by mounting between the pile head and reference beams. The micrometer has a range of 0-50 mm and an accuracy of 0.01 mm. 1.5 Reference Beam Two reference beams (channel 125x65x5 mm) will be cross-connected and laid on support, firmly embedded in ground with one end fixed and the other end freed. 1.6 Leveling instrument Relative movements of the test pile head, reference beam and anchor pile will be checked by a Shokisha precise leveling instrument with an accuracy of 0.01 mm. Readings will be made on ruler scale fixed on the reading points (1 point at pile head, 2 points at reference beams and 1 point at each anchor pile). 2.0 TEST PROCEDURE 2.1 Compression Pile Load Test The test shall conform to the modified ASTM D (Reapproved 1994) item 5.0 Standard Loading Procedure with load sequence in percentage of design load. Three cycles of test will be performed. Cycle 1 (maximum to 100% of the design load) A. The load will be added gradually by increasing from initial 0 to 25%, 50%, 75%, and 100% of the design load. B. When each load increment will be achieved, the next load increment will be added only when the settlement rate will be less than 0.25 mm per hour or after 2 hours, whichever shall occur first. C. At each load increment, load, settlement and time will be recorded at 1, 2, 4, 8, 15, 30, 60, 90, 120, 240 minutes and every 2 hours with an accuracy of at least 0.01 mm. D. The maximum load will be kept constant for at least 24 hours and then reduced to 75%, 50%, 25% and 0% of the design load, respectively. Each load will be maintained until the rate of settlement would not be greater than 0.25 mm per hour or after two hours, whichever shall occur first. E. At "0" load, rebound movement will be recorded at 1, 2, 4, 8, 15, 30, 40, 60 minutes and every hour thereafter until a constant settlement will be reached. Cycle 2 (QUICK TEST, maximum to 200% of the design load) 3

4 A. The load will be added gradually by increasing from initial 0 to 25%, 50%, 75%, 100%, 125%, 150%, 175% and 200% of the design load. B. When each load increment will be achieved, the next load increment will be added every after 5 minutes.. C. At each load increment, load, settlement and time will be recorded at 1 and 5 minutes with an accuracy of at least 0.01 mm. D. The load will then be reduced to 175%, 150%, 125%, 100%, 75%, 50%, 25% and 0% of the design load, respectively E. At "0" load, rebound movement will be recorded at 1, 2, 4, 8, 15, 30, 40, 60 minutes and every hour thereafter until a no further settlement will be experienced. F. The test pile will be considered failure when a rapid progressive movement of the pile in the direction of loading under a constant load or physical failure of the test pile is observed or a settlement of more than 15% of the diagonal dimension of the pile, which is equivalent to 90 mm. 2.2 Tension Pile Load Test The test shall conform to the ASTM D (Reapproved 1995) Standard Test Method for Individual Piles Under Static Axial Tensile Load. with load sequence as explain below. The test will be conducted until the pile exhibit signs of failure. Cycle 1 (maximum to 100% of the design load) A. The load will be added gradually by increasing from initial 0 to 25%, 50%, 75%, and 100% of the design load. B. When each load increment will be achieved, the next load increment will be added only when the settlement rate will be less than 0.25 mm per hour or after 2 hours, whichever shall occur first. C. At each load increment, load, settlement and time will be recorded at 1, 2, 4, 8, 15, 30, 60, 90, 120, 240 minutes and every 2 hours with an accuracy of at least 0.01 mm. D. The maximum load will be kept constant for at least 24 hours and then reduced to 75%, 50%, 25% and 0% of the design load, respectively. Each load will be maintained until the rate of settlement would not be greater than 0.25 mm per hour or after two hours, whichever shall occur first. E. At "0" load, rebound movement will be recorded at 1, 2, 4, 8, 15, 30, 40, 60 minutes and every hour thereafter until a constant settlement will be reached. Cycle 2 (QUICK TEST, maximum to 200% of the design load) A. The load will be added gradually by increasing from initial 0 to 25%, 50%, 75%, 100%, 125%, 150%, 175% and 200% of the design load. B. When each load increment will be achieved, the next load increment will be added every after 5 minutes.. G. At each load increment, load, settlement and time will be recorded at 1 and 5 minutes with an accuracy of at least 0.01 mm. H. The load will then be reduced to 175%, 150%, 125%, 100%, 75%, 50%, 25% and 0% of the design load, respectively I.At "0" load, rebound movement will be recorded at 1, 2, 4, 8, 15, 30, 40, 60 minutes and every hour thereafter until a no further settlement will be experienced. J. The test pile will be considered failure when a rapid progressive movement of the pile in the direction of loading under a constant load or physical failure of the test pile is observed or a settlement of more than 4

5 15% of the diagonal dimension of the pile, which is equivalent to 90 mm. 2.3 Lateral Pile Load Test The test shall conform to the ASTM D Standard Test Method for Individual Piles Under Lateral Load. with load sequence as explain below. The test will be conducted until the pile exhibit signs of failure. A. The load will be added gradually by increasing from initial 0 to 25%, 50%, 75%, 100%, 125%, 150%, 170%, 180%, 190% and 200% of the design load. B. When each load increment will be achieved, the next load increment will be added after each load duration shown in Table 3. C. At each load increment, load and time will be recorded at 1, 5, 10 minutes with an accuracy of at least 0.01 mm. D. The test pile will be considered failure when a rapid progressive movement of the pile in the direction of loading under a constant load or physical failure of the test pile is observed. During the load test, records including plots of load vs. time and load vs. settlement will be maintained progressively. 3.0 RESULTS OF TEST The test results will then be reported in the form of: Time, load, pile head movements, settlements and reference beam movements. Load-settlement curve. Time-settlement curve. Time-load curve. Report and recommendations on the ultimate pile capacity. 5

6 Fc'= 400 ksc. Pile Dia.= 0.46 m. Q= 270 Tons L= 12.8 m. A= 0.16 sq.m. Ec= 29,427 Mpa Ec= 3.00E+06 Tons/sq.m. Settle-1= 7.02 mm. Settle-1= 2.81 inch Settle-2= 0.50 inch Settle-2= 1.27 mm. Settle-3= 0.14 inch Settle-3= 0.35 mm. Total Settle= 3.44 inch Davidson Offset Line Limit= 3.44 inch Davidson Offset Line Limit= 8.75 mm. ESTIMATION OF ULTIMATE LOAD FROM PILE LOAD TEST BY DAVISSON METHOD

7 APPENDIX A TABLES, FIGURES & DESIGN CALCULATIONS

8 Table 1 Schedule of Loading Kaeng Khoi 2 Power Plant (Com pression Testing) Pile No. 385 Design Load = 65 Tons FS = 2 Test Load = 130 Tons Hydraulic Jack No./s 905 CYCLE 1: Maximum to 100% of the design load. Date Start Interval Load Pressure Remarks Time (hours) (Tons) (Bars) (%) 3-Jul 09: % 10: % 11: % 12: % 13: % 4-Jul 13: % 14: % 15: % CYCLE 2: QUICK TEST; Maximum to 200% of the design load. Date Start Interval Load Pressure Remarks Time (min) (Tons) (Bars) (%) 4-Jul 17: % 17: % 17: % 17: % 17: % 17: % 17: % 17: % 17: % 17: % 17: % 17: % 18: % 18: % 18: % 18: %

9 Table 2 Schedule of Loading Kaeng Khoi 2 Power Plant(Tension Testing) Pile No. 368 Design Load = 15 Tons FS = 2 Test Load = 30 Tons Hydraulic Jack No./s 912 CYCLE 1: Maximum to 100% of the design load. Date Start Interval Load Pressure Remarks Time (hours) (Tons) (Bars) (%) 6-Jul 09: % 10: % 11: % 12: % 12: % 7-Jul 12: % 13: % 13: % CYCLE 2: QUICK TEST; Maximum to 200% of the design load. Date Start Interval Load Pressure Remarks Time (min) (Tons) (Bars) (%) 7-Jul 15: % 15: % 15: % 15: % 15: % 15: % 15: % 15: % 15: % 15: % 15: % 15: % 16: % 16: % 16: % 16: %

10 Table 3 Schedule of Loading K aeng K hoi 2 Power Plant(Lateral Testing) Pile No. 416 Design Load = 7 Tons FS = 2 Test Load = 14 Tons Hydraulic Jack No./s 8 CYCLE 1: Maximum to 100% of the design load. Date Start Interval Load Pressure Remarks Time min (Tons) (Bars) (%) 10-Jul 09: % 09: % 09: % 09: % 09: % 10: % 10: % 10: % 11: % 11: % 12: % 12: % 12: % 13: %

11 ASTM ASTM Testing Co., Ltd. 1032/217 Phaholyothin 18/1 Road, Bangkok : (662) !5 : (662) CALIBRATION OF ONE HYDRAULIC JACK FOR STATIC PILE LOAD TESTING Kaeng Khoi 2 Power Plant (Compression Testing) LOADING UNLOADING Gage Rdg. LOADING (Tons) Gage Rdg. UNLOADING (Tons) in bars (Y) 905 TOTAL (X) in bars (Y) 905 TOTAL (X) Calibrated Regression Output : Regression Output : Constant Constant Std Err of Y Est Std Err of Y Est R Squared R Squared No. of Observations 10 No. of Observations 9 Degrees of Freedom 8 Degrees of Freedom 7 X Coefficient(s) X Coefficient(s) LOADING (Y) = * X UNLOADING (Y) = * X

12 ASTM ASTM Testing Co., Ltd Kampangpeth III Road, behind Jatujak Park, Bangkok THAILAND : (662) ~7, , , : (662) CALIBRATION OF ONE HYDRAULIC JACK FOR STATIC PILE LOAD TESTING Kaeng Khoi 2 Power Plant(Tension Testing) LOADING UNLOADING Gage Rdg. LOADING (Tons) Gage Rdg. UNLOADING (Tons) in bars (Y) 912 TOTAL (X) in bars (Y) 912 TOTAL (X) Calibrated Regression Output : Regression Output : Constant Constant Std Err of Y Est Std Err of Y Est R Squared R Squared No. of Observations 6 No. of Observations 5 Degrees of Freedom 4 Degrees of Freedom 3 X Coefficient(s) X Coefficient(s) LOADING (Y) = * X UNLOADING (Y) = * X

13 ASTM ASTM Testing Co., Ltd Kampangpeth III Road, behind Jatujak Park, Bangkok THAILAND : (662) ~7, , , : (662) CALIBRATION OF ONE HYDRAULIC JACK FOR STATIC PILE LOAD TESTING Kaeng Khoi 2 Power Plant(Lateral Testing) LOADING UNLOADING Gage Rdg. LOADING (Tons) Gage Rdg. UNLOADING (Tons) in bars (Y) 8 TOTAL (X) in bars (Y) 8 TOTAL (X) Calibrated Regression Output : Regression Output : Constant Constant Std Err of Y Est Std Err of Y Est R Squared R Squared No. of Observations 11 No. of Observations 10 Degrees of Freedom 9 Degrees of Freedom 8 X Coefficient(s) X Coefficient(s) LOADING (Y) = * X UNLOADING (Y) = * X