Three-Dimensioned Numerical Analysis Of Rigid Pile Composite Foundation And Modal Experimental Study

Rigid pile composite foundation not only can fully use the supporting capacity of natural foundation, moreover pile can display the frictional resistence whole body for its big rigidity, the load is transferred to a deeper soil layer. So the ground bearing capacity obtains a larger enhancement. Rigid pile composite foundation now is applied to many engineering such as high buildings and the extra-high buildings. But rigid pile composite foundation theory and computation analysis, which is quite complex and has more influence factor, can not be able to meet the project actual needs by far only depends on the experience and the simple method. At present, rigid pile composite foundation numerical analysis is mainly focused on plane strain two-dimension analysis or simple three-dimensioned numerical analysis. Regarding three dimensional group pile research, because of the troublesome modeling, long time computing, not easy to converge, the research material are not many. To the experimental study of rigid pile composite foundation, field test is not popular than modal experiment for the big investment, longer experimental cycle, poor repeatability, and the material is also less.This article, which tried to establish three-dimensioned numerical modal of rigid pile composite foundation, has done a deeper research on the influencing factors such as cushion thickness, cushion modulus, piles length, piles modulus, foundation stiffness, to study their influence on the bearing capacity and settlement of composite foundation, pile stress, stress of the soil around piles, pile-soil stress ratio. And some beneficial proposals are put forward for the rigid pile composite foundation optimized design.This article has also carried on modal experimental study to the rigid pile composite foundation. The settlement character, stress of the piles and soil around piles in different position is tested; the indexes such as pile-soil stress ratio, pile-soil load share ratio which reflect pile-soil performance together are researched.The results between numerical analysis and modal experimental test are tally with each other, the feasible of the numerical analysis is verified.