Behavior Of PHC Pile Composite Foundation And Optimization Method Research

With the use of construction land more and more and the lack of land, many bad foundation were used after artificial deal. By the Technology of Foundation treatment we can Improve the bearing capacity of natural foundation and reduce it's settlement. Currently, composite foundation has been widely used in construction as an important way of ground treatment. with a series of advantages, High-Strength Prestressed concrete pipe pile Composite Foundation have been used by large number of projects and have been became a widely used form of composite foundation. Also many Engineering Practice had proved that the High-Strength Prestressed concrete pipe pile Composite Foundation using can produced good results. At present it's theory lags behind practice and be confined to guide engineering Construction, So the study of composite foundation Theory has very important significance.This paper based on the basic theory of composite foundation, and introduced the load transfer mechanism of PHC pipe pile composite foundation, bearing capacity characteristics, settlement and bearing capacity analysis method. And it used Drucker-Prage model, DP materials element in ansys software to simulate soil. between soil and pile, the pile and cushion, soil and cushion layer to establish contact pair and the PHC pile composite foundation finite element model, in order to simulate composite foundation. According to the simulation results and PHC pipe piles with vertical compression test results of comparison, whether the model can correctly simulate the PHC composite foundation of pile and soil interaction was tested and verified.Further by finite element numerical simulation of pile-soil interaction, studied on the single pile and pile group under the PHC pile composite foundation bearing capacity of traits. The PHC pile composite foundation of pile length, pile diameter, cushion, pile spacing and a series of factors on the bearing capacity of composite foundation was discussed, based on the results discussed in pile-soil stress ratio, pile shaft resistance, column load of variation which changes with factors.According to the optimal design theory and the basic theory of composite foundation optimal design, stablish finite element model of four PHC pipe pile composite foundation and use the optimization of ansys software to optimize the pile diameter, pile length and pile spacing under the foundation bearing capacity and displacement control.