The Study Of Sawn-slot Diaphragm Wall On Application Of Roadbed's Moisture Damage Preventing In Expressway

The early moisture damage of asphalt pavements has been one of the uppermost distresses in expressway. As for the freeway been open to traffic now in China, they are inevitable that the rain water permeates through the asphalt pavement surface and the super stratum backwater infiltrates through the pavement layer. How to prevent it efficiently has been a problem that highway engineers pay much attention to.We advance a new measure to control the ubiquitous water-induced distress. A sawn-slot diaphragm wall is constructed on the inside or outside of the median separator. Its bottom is embedded in the roadbed which is relatively impervious. The wall can prevent the surface water and backwater permeating through the pavement layer from the median separator to ensure the super stratum of the roadbed and the pavement are dry the most of time.It includes geomembrance mid and serosity coagulation zogomorphous,the geomembrance provide the better permeating capability.The serosity coagulation fix up the geomembrance to the middle of the wall and fill in earthy cranny of the outer rock interface to increase the permeating capability zogomorphous part.It is studied for the first time that the sawn-slot diaphragm wall is used in median separator of the expressway.its studied aspect only emphasize structure technics but it is not done that analysis the seep effect of the wall from mathematic calculation.This paper applies FLAC^3D to set up mathematic model which is simulated numerically subsequently. We mostly do several faceted jobs as follows: (1)we simulate the change of the seepage field with fluid-solid coupling method. The results indicate that the wall can avoid effectively the water in the median separator permeating through the pavement layer. It achieves the prospective effect. (2)On the basis of that, The changes of displacement and stress that the wall is constructed whether or not are simulated. The analyses of horizontal and vertical displacement and maximum and minimum main stresses are given in the paper. The results indicate that it is small that the wall effects the roadbed's displacement and stress. It provides reference for the stability of the roadbed. (3)Then the stress distribution and displacement of the wall are analyzed,we know that the distortion is basal harmony between the wall and around soil,so that the wall is safe.(4)Finally we compute the stress of the geomembrance that is brung along with the wall's distortion. The results indicate the stress and distortion are small,it satisfy request.Through the study of applying the sawn-slot diaphragm wall to prevent the moisture damage in expressway, we can draw some universal conclusions. These conclusions provide instruction to the construction, provide theoretical basis to the stability of the wall and the effect of avoiding seeping. While promoting its further theoretic development, it will extend the use of technology.