Centrifugal Model Test And Numerical Simulation Of Subgrade Widening And Reinforced Slope

In recent years,with the rapid development of China's economy,the traffic volume is increasing day by day.The highways in the developed coastal areas are in an overloaded state for a long time.At the same time,the existing highways and low-grade highways in the central and western regions cannot meet the current traffic demand.It is necessary to widen the road to ease the pressure from traffic.At present,the widening and rebuilding of expressways is faced with many problems such as difficulty in land acquisition,poor bearing capacity of foundations,uneven settlement,etc.The reinforced slopes have been gradually applied to highway widening projects because of their stability and low land occupation.However,existing research is clearly behind engineering practice.Therefore,research on highway widening and reinforced slope has important theoretical significance and engineering application value.Firstly,three groups of roadbed widening and reinforced slope centrifugal model tests were carried out to study the influence of foundation strength on slope deformation and stability.The selection of material model materials and stress measurement of core materials in centrifugal model test are the key,through a variety of materials.Tensile test and interface friction test are used to select the reinforced material model material.At the same time,the strain gauge is attached to the reinforced material to monitor the distribution and variation of the rib during the deformation process.The basic parameters of the centrifugal model are established.The three-dimensional finite element numerical model is used to verify the rationality of the numerical simulation results by comparison with the centrifugal test results,and further expand the research to analyze the main influencing factors of the roadbed widening and reinforced slope.Research indicates:(1)The strength of the foundation significantly affects the deformation and stability of the reinforced slope.When the reinforced slope is located on the weak foundation,the slope deformation is large and the instability is easy to occur;when the local base strength is gradually increased,the slope deformation is obviously reduced,and the slope stability is significantly improved.(2)The tensile force of the reinforcement is mainly affected by the plastic zone and the circular sliding surface.The internal force of the reinforcement will suddenly change near the position of the circular sliding surface.By applying epoxy resin tape on the surface of the rib material and attaching the strain gauge,the stress distribution law of the different burial depth ribs of the reinforced slope during the operation of the centrifuge is accurately reflected by calibrating the force relationship between the strain gauge and the rib.(3)Through the comparison with the results of the centrifugal model test,the rationality of the three-dimensional finite element model of the roadbed widened reinforced slope is verified,and the research results of the centrifugal model test are further expanded by the analysis of the strength of the reinforcement and the parameters of the filler.Figure[58]table[14]reference[84]...