Mechanical Response Analysis And Joint Optimization Of Precast Cement Concrete Pavement

Precast cement concrete pavement is a new type of green cement concrete pavement system assembled by small-sized cement concrete precast slabs on the base.Compared with the traditional cast-in-place cement concrete pavement,it has the advantages of fast construction speed,low disassembly and maintenance costs,and low environmental pollution.When used as a temporary pavement,due to its recyclable characteristics,it greatly reduces resources and Cost wastage.As the pavement system is assembled from many prefabricated panels,resulting in poor pavement integrity and frequent occurrence of plate damage,so it has not been widely used in traffic engineering.Therefore,this thesis will analyze the causes of these problems in response to this phenomenon,and make optimization suggestions for the traditional fabricated cement concrete pavement.The main research work is as follows:Firstly,in this thesis,two new types of jointed cement concrete pavement joints are proposed.By analyzing the problems of traditional prefabricated cement concrete pavement,it will increase the load transfer capacity of the mouth,reduce the tensile stress at the bottom of the slab,and control the relative displacement of adjacent plates.The optimization goal of the prefabricated cement concrete slab is to limit the opening of the joint and For the purpose of controlling the relative displacement of adjacent plates,a new type of cemented concrete pavement joint form using embedded groove joints is proposed for gentle road sections;an end based on embedded grooves is proposed for steep slope sections The new type of assembled cement concrete pavement joint form interlocks with additional buckle structure.Secondly,using the finite element software to establish three-dimensional models of assembled cement concrete pavement with two new types of joints,and perform numerical simulation analysis.With the goal of increasing the load transfer capacity of the tongue and groove and reducing the tensile stress at the bottom of the board,the mechanical response of two new types of jointed concrete pavement under different tongue and groove thickness,tongue and groove depth and slope gradient conditions Through analysis,the influence of various factors on the load-carrying capacity and the maximum tensile stress of the bottom of the new fabricated concrete-concrete pavement is obtained.Based on the results obtained from the analysis,suggestions for optimizing the joint size are proposed.Subsequently,the two optimized cement concrete pavements with new types of joints obtained by the final optimization were taken as the research objects,and the distribution rules of their load transfer capacity along the joint length and the load stress under the contact state of different surface layers and base layers were analyzed respectively The law of change and the fatigue life of the panel.Finally,based on the economic evaluation,the thesis compares the new type of precast cement concrete pavement with the traditional cast-in-place pavement and the traditional precast cement concrete pavement from two aspects of economic and socialbenefits,and measures its use value.The research results of this thesis can provide a reference for the design of prefabricated cement concrete pavement,and have reference significance for the research of cement concrete pavement joint structure.