A New Method For Calculating Ultimate Bearing Capacity Of Rigid Pile Composite Foundation

Rigid pile composite foundation has been widely used in engineering for a long time. However, there are still some deficiencies in the design theory and calculation methods.According to present code, the bearing capacity of rigid pile composite foundation is calculated by eigenvalue method, but the eigenvalue method is difficult to reflect the actual state of the foundation. The ultimate bearing capacity of the pile foundation is calculated by Technical code for building pile foundation, it does not match the characteristic value of bearing capacity of composite foundation. Coefficient of bearing capacity of soil between piles in composite foundation has no specific value method, it is difficult to give the corresponding value in different geological conditions and different basic situation conditions.In this paper, the bearing capacity of rigid pile composite foundation is studied,and for the above questions, a new method for calculating ultimate bearing capacity of rigid pile composite foundation is proposed. This method is used to solve the ultimate bearing capacity of rigid pile composite foundation from the perspective of stability, and modified density method is used convert the interaction between pile and soil, the ultimate bearing capacity of soil between piles and ultimate bearing capacity of pile is calculated. Considering the failure mode of the foundation, ultimate bearing capacity of global sliding failure?midline sliding failure and free sliding failure is calculated. Based on the calculation and analysis of homogeneous and layered foundation, considering the influence of foundation width and replacement ratio on the rigid pile composite foundation. Get the following rules. Relationship between ultimate bearing capacity and replacement ratio of soil between piles, and the relationship between ultimate bearing capacity and replacement ratio of composite foundation; Along with the change of base width, when the bearing capacity of composite foundation reaches the ultimate bearing capacity, the failure mode will also change; The relationship between ultimate bearing capacity and foundation width of composite foundation, and the relationship between foundation width of composite foundation and ultimate bearing capacity of soil between piles; Effect of foundation width on the bearing capacity of soil between piles, effect of replacement ratio on the bearing capacity of soil between piles; The influence of foundation depth on bearing capacity of composite foundation. Through the calculation method of bearing capacity,it can be used to calculate the ultimate bearing capacity of soil between piles in the reinforcement area before and after reinforcement. Thus, different foundation can be obtained specific influence coefficient of Bearing capacity of soil between piles. The calculation method is used to calculate the foot size test and f ield engineering cases,the calculated results are compared with the experimental results, and compared with the actual case of the project, the results show that the method is in good agreement with the experimental results, and can correctly reflect the actual situation of the project.