FORMULATION OF NUMERICAL TECHNIQUE TO DEVELOP t-z CURVE USING LOAD SETTLEMENT DATA FROM PILE LOAD TEST

Abstract

Until recently very few successful attempts, have been made to analyze the behavior of piles and pile systems. This is partly associated with the historical development of piling in that a strong tradition of empiricism has become part of the folklore of piling. When one attempt to take into account aspects such as the effect of pile installation major difficulties apparently arise, but the fact that a complete solution cannot be derived does not preclude the use of analytical approaches based on simple models of soil behavior.In this paper a simple numerical technique based on load transfer approach is developed to capture the response of the soil to displacement, as experimental technique of instrumenting the pile along the length of pile would have been very costly. This technique uses the available load settlement data from pile load test not instrumented along pile during load testing and back figures the response of soil along pile length.Once the load settlement response of soil along pile length is known, the curves can be used for the same site to study the effect of different length and/or diameter of the pile on the load settlement curve of pile. In addition, the load settlement curve for other sites can be generated if the soil profile does not vary remarkably from that soil profile from which the load settlement response of soil is developed. This technique is then applied to load settlement data of three pile load tests conducted in various localities of NWFP.