Stability Evaluation And Analysis Of Surrounding Rock Of Ling Chuan Expressway Tunnel

Tunnel surrounding rock classification is very vital for tunnel design and safetyconstruction. As the scale of tunnel engineering is more and more big and Geologicalengineering is more and more complicated, Highway Tunnel Design Specification shows itslimitations. This paper is based on the LingChuan highway tunnel under construction, andSummarized the previous engineering experience and research results, combined thelaboratory experiment and field practice, as well as qualitative analysis and quantitativeevaluation, then discussed the main factors Affecting the stability of LingChuan highwaytunnel surrounding rock and classified Tunnel surrounding rock. At last, maintained thefollowing results through the study.(1) The Main factors affecting the stability of LingChuan highway tunnel surrounding rockIncludes these several aspects: hardness degree of rock, structural integrity of the rock mass(2) Combined with previous experience, set up the scheme of qualitativeclassification of LingChuan highway tunnel surrounding rock through studying thedecision process and methods of hardness degree of rock, structural integrity of the rockmass. Classify Tunnel surrounding rock by the method above, and it receives preferableapplication effect.（3）Classify the Tunnel surrounding rock of LingChuan highway tunnel by BQcorrection method based on qualitative classification and achieve the final result which canProvide a reference basis for the tunnel design and construction.（4）Classify the Tunnel surrounding rock of LingChuan highway tunnel by extensiontheory. Select this five indices including hardness degree of rock, structural integrity of the rockmass, buried depth of tunnel, main weak structural plane, elastic P-wave velocity, make theseindices dimensionless, establish Classical field matter-element and Section field matter-elementDetermine the factor weight，achieve the final result of qualitative classification at last.（5）Contrast the two results achieved by extension theory and BQ correctionmethod, analysis the reasons that why they are different, find that the result byextension theory is closer to the truth. It can be used widely in practical engineering.