| At present,precast pile composite foundation is widely used in the field of housing construction,highway and municipal construction,especially in the last ten years,the application technology of composite foundation has made great development.However,the precast pile composite foundation technology is still lacking in active research and application in water conservancy projects.In soft soil area,the former sluices,pumping station in the design of hydraulic structures such as fcundation treatment,precast pile is a kind of commonly used foundation treatment measures,but in the precast pile design usually does not consider the role of natural soil to participate in and share the top load,so as to make the design safety degree is larger,the whole project be safe,and then make the project in terms of investment caused a certain amount of waste.For this reason,composite foundation is necessarily applied to the foundation treatment design of the gate station,by which,the benefits of "making the best use of everything" and reducing project investment could be achieved.Based on the above viewpoints,this paper carries out calculation and analysis on specific engineering examples,and draws the following conclusions:(1)According to the basic definition and classification principle of generalized composite foundation,the formation conditions and several common concepts of composite foundation are summarized,and the basic calculation theory and method of bearing capacity and settlement of rigid pile(precast pile)composite foundation are introduced,and the theory and thinking of optimal design of composite foundation are analyzed and explained.(2)Combined with specific engineering examples,the conventional precast concrete pile foundation design is carried out according to the gate station engineering stability calculation,and the bearing capacity and settlement calculation are completed according to the pile foundation calculation method,and the corresponding analysis is made.(3)The three-dimensional finite element analysis model of prefabricated pile composite foundation and gate station floor is constructed with a specific engineering example.The stress,strain and mechanical properties of prefabricated pile composite foundation under load effect are analyzed and studied,and the settlement value of prefebricated pile composite foundation is compared with that of conventional pile foundation.(4)Considering the effect of floor structure of gate station,the interaction characteristics among floor,pile and soil between piles under different working conditions are studied.The influences of external load,soil parameters between piles,stiffness of precast pile and floor stiffness of gate station on settlement of precast pile composite foundation,horizontal displacement of pile top and load sharing of soil between piles are analyzed,and curve fitting of relevant influence parameters is made,and the corresponding change rule is obtained. |
