Guiyang City, Off Highway Bridge Platform Pile Foundation Internal Forces Influencing Factors

Pile foundation that is composed of cap and pile group is one of the important types of bridge foundation in highway and railway, and meanwhile it is also one of the difficult points in the design. Al the current technical codes of our country in relation with the design of pile-cap foundation are based on the assumption of absolutely rigid cap, namely the deformation of the cap itself is not taken into consideration and only the rigid translation and angles of rotation of the cap are taken into consideration. In fact, the existent pile-cap model tests, analyses and computations show that the assumption of absolutely rigid cap doesn't come true on some particular conditions and instead of it the numerically computational method of "m method pile-elastic cap" can reflect the lo adding status and deformation of pile-cap system better.The rock-socketed pile foundation of Xiaoguan Bridge newly built. The following works have been completed.1.The rock-socketed pile is treated with the "Single Road Simplification" equivalent method. The pile-cap system under different loading conditions is computed and analyzed with the finite element softwares ANSYS based on the "m method pile-elastic cap" method.2.The influences of the proportional coeficient (m) and the pile length above ground (10) on the axial force, shear force and bending moment at pile top are analyzed.3.The influences of the axial rigidity of pile on the axial force, shear force and bending moment at pile to pare analyzed.