Under The Action Of Vehicle Load Path-soft Soil Structure Dynamic Response Analysis

The study of traffic load on the dynamic response of the various structural layers inthe road has become one of the engineering special attention, and academia has longbeen a key research topic, because of many problems after engineerings. Theimprovement of the economic development,the faster travel rate and the acceleratingrhythm of life make more and more highway roadbed on the soft soil and at the sametime after the work of problems also is a major concern. Between the highcompressibility and low strength of soft soil and the dynamic and long-term traffic load,increased the difficulty of the research on dynamic response under the traffic load onroads and subgrade and foundation is to work and influence together, commondeformation characteristics under traffic load is also a question worth exploring.Considering the high compressibility and low strength of soft soil and the dynamicand long-term of traffic load, the current hypothesis subgrade for linear elasticmulti-layer system and the theory of equivalent traffic load to a static load lack certainpowers of persuasion are differ from the actual working condition.Therefore, thestudy of traffic load urgent transition from static to dynamic, the subgrade soil by usingthe linear elastic model of foundation soil by using the elastoplastic model is a morecomplex situation.The main content of this paper mainly divided into the following five sections:This paper according to the practical engineering case is put forward the researchpurpose and meaning, from theoretical research progress, on the field test progress,innumerical analysis progress of three aspects introduced the current research situation ofthe traffic load on road.The second part introduces the theory basis of numerical calculation，First,describe the dynamic characteristics of weak soil, pavement materials and compositefoundation briefly, then this paper introduces the characteristics of the traffic load anddetermine the suitable simplified model.The third part is based on the existing numerical calculation of theoretical basis, bya typical soft soil road for various structural layers in the model, established the road3dmodel.This paper adopts double after foundation model to simulate the reinforcementof soft soil subgrade, surface using linear elastic constitutive relations, roadbed andcomposite foundation using elastoplastic constitutive relation. Use the finite elementsoftware to make the finite element analysis program. By the method of three-dimensional dynamic finite element unit, subgrade under traffic load transientanalysis.The fourth part from the single and double lane vehicle load as the breakthroughpoint, analysis of single vehicle load when driving on road structure system and theinfluence of the two-lane traffic load at the difference of effect on the system of roadstructure, under the analysis of vehicle load superposition effect.The fifth part based on the current path of the main causes of disease on thepremise of single vehicle loads. And from different aspects, include vehicle load，vehicle speed to research the different factors influence on dynamic response of thevarious structural layers in the road.