| The karst areas covered widely in the mid-west areas of China, where is also rich of coal and mining resources. With the long history of underground mining exploitation, goaf area is also covered widely. The karst caves and goaf are described as cavity areas in the thesis. With the implementation of "West Development Strategy" and with the development of urban construction in these areas, many highways will cross these cavity areas. Meanwhile, we have to face the problem of subgrade stability loss and damages which are caused by the collapse of cavity. Based on above background and the actual projects, the article conducted the research on the cut stability evaluation of subgrade at the cavity area and treatment measures of the project.The thesis give an detailed and systematic analysis on the typical disease of cavity areas on the subgrade of constructed highway. And it also described the natural and some man-made factors which influence the stability of goaf and karst cave on the highway. The thesis discussed the stabilization evaluation methods of goaf and karst areas on the subgrade. At last, the measures of the subgrade disease in goaf and karst cavity areas were introduced. Reveal the dynamic cavalcade of rock mass destructive in karst region of subgrade engineering by the finite element destabilization intensity subtract back analysis system, especially reappearance the change law of the failure of top tray at karst cave and collapse on landsurface.use stability analysis theory and method of slope/W, analysis stability of collapse unstability body coalition both physical mechanics test and analytic result of collapse unstability body. lodge the suggestion treating measure for high steep cut local instability and numerical simulation analyses reinforce effect, systemic research on stabilization assessment technique, design and construction dispose, quality test about underlay goaf and karst engineering geology of freeway by scientific method, procure prominence effect.In the last part of the thesis, it summarize what measures and the methods should be taken when encounter these kind of typical problems. It also gave conduct to the design and construction of the highways at the goaf areas in mountainous highways. |
