Study On Rigid And Flexible Static Loading Test Of The CFG Pile Composite Foundation In Bejing-Shanghai High-Speed Railway

Cement Flyash Gravel Pile (The CFG pile) is a new type of technique for improving the weak ground.It can improve the bearing capacity of the composite foundation greatly, and have a small settlement close to stability with high speed.The CFG pile has already been applied in foundation engeneering.With High-Speed Railway's development in China,it also has been used in High-Speed Railway's ground treatment.As a kind of rigid pile,its bearing capacity and settlement are detemined by the static loading test.However,the traditional method of static loading test is good for the industrial and civil buildings'rigid foundation,but not flexible foundation of the High-Speed Railway. Therefore we should find a new method to replace the traditional one.The research results at home and abroad of CFG pile composite foundation are summarized.The reinforcement mechanism,the calculation methods of bearing capacity and settlement are respectively introduced.In this paper,combining the pratical project and using FEM analysis program (ANSYS),the flexible static loading test method is studied.According to the comparison between the theoretical results and the measured ones, The new method is more suitable for the flexible foundation.Several suggestions have been made for the further research on the static loading test of the CFG pile composite foundation.