Analysis On Dynamic Response Of Soft Clay Foundation Under Traffic Loads

With the rapid development of national economic, the infrastructures are widely building.Including many highways ,railroads,airport roads and dams. Restricted by geography position, many freeways have to be built on the soft-soil ground.Settlement calculation of pavement or airport runway under traffic loads is one of most concerned problems in engineering ,as well as a key subject in academic area. Because of low intensity, high compressibility, low permeability and rheology of soft-soil, technology of freeway construction becomes more difficult and complicated. From the investigation about running of freeway, settlement of embankment after work are universally considerable.Firstly,the paper introduced the present study and meanings on dynamic characteristics of soft clay foundation under traffic loads.Then generalized the present study state on the problems of dynamic responses of soft clay foundation from theory study,experimental modeling and numerical analysis aspects.Secondly,some basic theories and methods on soft clay foundation under traffic loads are generalized.Including the constitute of soft clay, the simulation of traffic loads and some basic definition ,theories about Finite Element Method.Thirdly,since the characteristics of transportation loads and then movable invariable load and stable simple harmonic load are decided on as the simulation of transportation loads, the project to be studied is simplified as a problem of plane-strain, and using both linear-elastic model and elastic-plastic model, transient response of composite ground under transportation loads are analyzed with FEA method. The main contents are as the following:1. Viewing the longitudinal section of subgrade as the studying target, traffic load is simplified as half-sinusoidal load. Firstly, considering the exact solution of thedisplacement in the elastic half-space under half-sinusoidal load,the solution are compared with computering solution on same conditions.Based on that ,the solution of the FEA modals are reasonable and reliable.Then,the dynamic responses of linear-elastic model and elastic-plastic model under half-sinusoidal load and movable invariable load are analyzed.2. The dynamic responses of highways and soft-clay foundation under half-sinusoidal load and movable invariable load are analyzed,considering the effects of load and parameters of highways and soft clay foundation.3. The dynamic responses of highways,composite foundation and soft-clay foundation under half-sinusoidal load and movable invariable load are analyzed,considering the effects of load (including traffic velocity)and parameters of highways,composite foundation and soft clay foundation.