Research On The Static And Dynamic Properties Of The Foundation-pavement Structure System

In recent years, with national investment policies to favor the construction of infrastructure facilities, the highways, airports, wharf buildings have been rapidly developed, correspondingly, the studies on the static and dynamic properties of the foundation-pavement structure system have drawn more and more science workers' attentions. The most applied method to the calculation of the foundation-pavement structure system was the method bases on the simple Winkler model. With the rapid development of road transportation, the soar of all kinds of heavy and special vehicles, the augmentation of vehicles density and the rise of various vehicle loads etc, which make the research became complex, so the present research findings can't satisfy actual requirements.In this paper, based on the study and analysis of the foundation-pavement structure system, analysis method (using multiple Fourier's series method) and numerical method (finite-infinite element coupling analysis method) are individually used to analyze the static and dynamic properties of the pavement structure. Especially the random finite-infinite element coupling model is established, the random analysis methodology and computing program of the foundation-pavement structure system under random moving loads are presented. The main work is as follows:(1) The analytic theory and method of the f foundation-pavement structure system are present. Multiple Fourier's series method is extended to analyze the static, vibration and flexion problems of the thin plate, medium plate, composite materials road slab on the elastic foundation in various boundary conditions. Particularly creative solution is used in solving vibration and flexion problems, which are converted to the problem of matrix's generalized eigenvalue problem, which simplify the calculations greatly. The more important is the solution can be used to solve various elastic supported issues such as point prop, variation factor curve prop and heterogeneous foundation etc. Also multiple Fourier's series method isapplied to rectangle pavement slab, rectangle composite materials slab, orthotropic rectangle pavement slab, anisotropic rectangle pavement slab, anisotropic parallelogram pavement slab besides rectangle road thin plate.Because multiple Fourier's series method converge slowly, it was seldom used, theoretical deduce or converted into single Fourier's series method was done by previous author, which was little value. Computer is very popular now, and its performance has been greatly improved, so the question that multiple Fourier's series converge slowly has not been a problem, moreover, means to accelerate its convergence have been done so multiple Fourier's series method can achieve sufficient accuracy.(2) The analytical method of solving the contact and disengagement problem of the interavtion between road slab and foundation is present, which is based on zoning generalized variational principle. Starting from the zoning generalized potential energy functional of the plate-foundation system, the zoning generalized conforming element method of the foundation-pavement structure's dynamic response under arbitrary traveling load is present, which is by establishing and analysing the potential energy functional of plate element area, foundation element area, and the contact element area. The foundation-pavement structure system's dynamic response under arbitrary traveling load is solved. By Newmark method, the method in this paper is proved to be efficacious though MATLAB program.(3 ) The numerical calculation method to solve the static and dynamic problem of the half-space elastic foundation is present. Finite-infinite element coupling model is established, and the static and dynamic properties' calculation method and program of the pavement structure on the elastic foundation. The actual boundary condition problem is solved, which is hardly be solved by finite element method only. It's benefit to physical engineering application.( 4 ) The static and dynamic problem's numerical calculation method of the foundation-road system on the half space elastic foundation is present. According to the principle of d'Alembert, the system's motion equation is estabished, and its static and dynamic properties are analysed. In which, the plate is simulated as 4-node rectangular plate element, the foundation under the plate is simulated as 8-node and 3-D finite element model, the infinite area is simulated as 8-node and 3-D single way infinite element and 7-node pentahedron both way infinite element model. The dynamic response problems of the rectangular thin and thick plate on the half-space elastic body under arbitrary moving load are solved. Using Wilson-0 method, the points' dynamic response values in thefoundation-road slab system under moving load in different time and different sites are worked out by corresponding MATLAB program. Through numerical calculation, the dynamic response problems are verified to be effective.(5) The random response analytical model of the foundation- pavement structure system based on the half-space elastic body is present, at the same time, the randomness of the material parameters and the vehicular loads are considered, the random element analytic method is given, and the design of the program is complete.Using the random finite-infinite element coupling method, the dynamic responses of the pavement structure are researched, which provides more efficient theory and method for the design of pavement structure.