Study on optimum design of cfg pile composite foundation under flexible load

Through the study on optimum design of CFG pile composite foundation, the following conclusions are obtained. (1) In accordance with the proposed principle of optimal design of CFG pile composite foundation under flexible load, post-construction settlement is clearly defined. (2) According to post-construction settlement of subgrade and efficiency factor of pile caps and soil, the factors that impact the settlement and bearing capacity of CFG pile composite foundation are analyzed. The optimum design according to settlement is important when the primary purpose of adopting composite foundation is to decrease settlement. The pile length and replacement ratio are two main factors influencing the settlement of composite foundation. (3) By comparing the economic benefits of design program that meet requirements of post construction settlement of roadbed and efficiency factor of pile caps and soil of composite foundation, two optimum design programs are selected. © 2011 ASCE.