Application Of Block Theory In The Analysis Of Surrounding Rock Mass Stability In Arch-Tunnel Of Expressway

The change of the natural stress state in rock masses leads to unloading and stress redistribution in the course of the construction of expressway tunnel.When the surrounding rock masses can't bear the rebound -stress and the redistribution stress ,some blocks will lose stability to slide along structural plane,furthermore ,causing the stability-losing failure of engineering rock masses.It will influence the safety and progress of construction directly.Block Theory is a kind of method developed and perfected in recent years,which analyses the stability of engineering rock masses.With further study and acknowledge of the scholars home and abroad,the reseach method has been comparatively ripe. Block Theory is being accepted extensively.According to the data relevant to tunnel Manxie 4 ,one of Simao-Xiaomengyang expressway tunnels,and based on the geologic drawing(including the layout of structural plane in the top and wall of the tunnel)worked out in construction site.The thesis constructs entity models of tunnel and structural planes,and analyses the the stability of blocks which are made of tunnel freefaces and the structural planes in rock masses with vector operation.AU the results have been obtained at the promise of having made sure the location of discontinuity.In order to make this kind of analytical method be applied to scientific research and construction,the author has carried on the development of analytical software in Windows operation system.And in the course of software development,the author compiles the software with Matlab,meanwhile designs and draws the figures with it.The software provides several convenient interface .It can realize several functions,including data input,calculation,text and graphic display (such as animation,zoom in and out,rotation) of analysis results.It can accomplish the analysis of rock masses stability in expressway arch-tunnel in no time.At last, by analysing and comparing the calculation results with the monitor and measuring results, the thesis testifies the reliability of the calculation results.By using the system,we can obtain the results quickly and exactly instead of doing complicated things.So it is a good way to study the stability of blocks in expressway arch-tunnel.