Behavior of Soil-Pile Interaction of Barrette Pile under Lateral Loading

Abstract

Construction of project using lateral load pile, the important data for analysis and design is p-y curve which have been generally established by different theory. However, the calculated p-y curves by theory mostly differ from the data referred to the field. Therefore, this research aims to study p-y curve by backed analysis from lateral pile load test in the field and compare to Matlock's theory by LPILE program.Additionally, the influence of the horizontal cyclic loading is considered to this research. In the research field, the barrette pile size 0.8 x 0.2 m was constructed in the area of MRT Green Line Extension project, Samutprakarn province. The lateral static load tests under stress control were focused on 10 cycles. For the first cycle, the forces were applied to the plie with 196 kN, 392 kN, 587 kN and 785 kN, respectively. For cycles 2nd – 10th cycle, the forces were applied only 785 kN. The inclinometer and Vibrating Wire Strain Gauge (VWSG) was installed in the barrette pile for lateral displacement and strain. The analysis result indicates that the p-y curves by back analysis method are higher than the curves of Matlock's method. However, under repeated loading 2nd – 10th cycle the p-y curves trend to decrease and drop down to the line of Matlock's theory in the zone of large deflection due to decreasing of soil stiffness