Mechanical Properties And Numerical Simulation Analysis Of Large Diameter Cast-in-Place Pile With High Steep Slope

Currently,with the continuous development of highways and railways,the pace of economic development of China's western development is getting faster and faster,large diameter cast piles are increasingly used in the form of viaducts.The viaduct will shuttle in the high mountains and lofty Hills Region,In order to protect the vegetation in the mountains and reduce the large area of excavation,large diameter cast-in-place piles are generally used in high and steep slope sections.But the mechanical properties and bearing capacity of large diameter cast-in-place piles with high and steep slope,domestic and foreign research on its theory and the application of engineering practice is far apart.In practical engineering,the cognition of the mechanism of its load transfer is not in place,there also exist unreasonable places in the analysis of bearing properties of the pile foundation,therefore,it is unable to be effectively designed and guided for large diameter cast-in-place piles with high and steep slope,which seriously hinders its development.Consequently,the study on the bearing capacity of large diameter cast-in-place pile is not only the need of the development of pile foundation theory,but also the urgent requirement of Engineering.In this paper,first of all,on the basis of reading a lot of literature,the mechanical properties and bearing capacity of large diameter cast-in-place piles with high and steep slopes are summarized,and its internal force calculation method is studied,finally,the finite element software is used to simulate,the factors influencing the bearing capacity of large diameter cast-in-place piles are summarized and concluded.The main research work of this paper is:(1)The mechanical properties of large diameter cast-in-place pile with high and steep slope is analyzed and summarized,Respectively,to do a comprehensive and systematic study on the pile-soil interaction system under the action of vertical load and horizontal load,simultaneously,the various factors that affect the load transfer behavior of large diameter cast-in-place pile system with high steep slope are compared,on this basis,the bearing capacity of pile foundation system and the interaction between pile foundation and soil are discussed,which laid the foundation for subsequent assumptions.(2)According to force and bearing capacity of large diameter cast-in-place pile system with high steep slope,the various external forces under the pile foundation are reasonably simplified,through the analysis of the monolithic construction,the differential equations of each characteristic segment are established,and the differential equation is solved by finite difference method,And the expression of the internal force and displacement of the pile foundation is obtained,which is used for programming the relevant procedures for engineering practice.(3)After a general introduction to the MADAS GTS finite element software,in view of the contents of this paper,it create a geometric model,and through the set of pile foundation and soil body's simulation parameters,boundary condition setting and grid division,on the basis of the simple summary of the calculation results,the analysis of the internal force and displacement of the pile foundation is carried out on 51 models under different factors established in this paper,which provides a basis for the design of pile foundation in engineering.