Numerical Analysis Of The Anti-Cracking Effect Of Twisted Steel Wire Mesh In "White To Black" Pavement

Under the long-term traffic load and the external environment,the cement concrete pavement will have many diseases,and the road performance will gradually decrease.Adding an asphalt layer on the old cement pavement can effectively improve the pavement performance.However,due to the two material mechanics There is a big difference in performance,due to the existence of joints in the old cement pavement,and the structure of the added pavement is prone to reflection cracks.In this paper,a layer of twisted steel wire mesh is added between the old cement concrete and the asphalt overlay to delay the propagation of reflective cracks.The pavement structure model is established by Abaqus finite element software to study the effect of adding twisted steel wire mesh on reflective cracks.The main research contents are as follows:(1)Establish a pavement model without a transfer rod and a pavement model with a transfer rod,and use the DLOAD subroutine to apply the moving load of the pavement.By changing the thickness of the asphalt overlay,the modulus of the asphalt overlay,the thickness of the old cement concrete pavement,and the Cement concrete pavement modulus,foundation modulus and axle load parameters are used to analyze the maximum principal stress,maximum shear stress and equivalent stress at the bottom of the overlay layer,and the influence of the above parameters on the pavement stress is obtained.(2)Comparing the changes in the bottom stress of the two pavement models under the condition of laying twisted-pair steel mesh and not laying it,laying the twisted-pair steel mesh will make the maximum principal stress and maximum stress at the joints of the asphalt overlay.Both the shear stress and the equivalent stress will decrease.The maximum principal stress value of the pavement model without the transfer rods will decrease by 19.3%on average,the maximum shear stress will drop by 16.2%on average,and the equivalent stress will drop by 16.4%on average;The maximum principal stress of the pavement model decreased by 19.2%on average,the maximum shear stress decreased by 20.2%,and the equivalent stress decreased by 20.3%on average.(3)Establish the temperature field model of the pavement structure,use the FILM subroutine and the DFLUX subroutine to obtain the time-varying pavement temperature field,and obtain the change of the temperature stress under the change of the temperature field within a day.The result shows that the twisted pair is laid under the action of the temperature stress.The maximum shear stress of the steel mesh pavement structure decreased by 70.0%,and the equivalent stress decreased by 67.6%.The 17 o’clock is the most unfavorable moment of the temperature stress of the pavement structure.At the most unfavourable moment of temperature stress,the sequential coupling method is used to superimpose the moving load,and the maximum shear stress of the steel mesh pavement structure under the coupling of temperature-load is reduced by 62.7%,and the equivalent stress is reduced by 62.9%.