Back-analysis for design parameters of large diameter bored plies

Abstract

Field test data from three instrumented large diameter bored piles in Pattaya city of Thailand were analyzed to study the behavior of load transfer mechanism from the pile to soil. The pile load test data were obtained from conventional static load test. These bored piles used for conventional static load test have the same diameter of 0.80 m and different length in the range of 25 m to 32 m. Results from back-analysis found that the skin friction resistance, (beta), has the value between 0.20 and 0.64 and the bearing capacity at end of piles, N[subscript q], which is in the range of 10 to 150, is much lower than the theoretical values proposed by other researchers before.