DETERMINATION METHOD OF SHEAR STRENGTH BASED ON CLASSIFICATION OF ROCK STRUCTURE SURFACE

The shear strength of rock mass discontinuity is one of the important parameters for rock slope stabilization analysis. In order to determine the parameters reasonably,a method is proposed on the basis of the classification of rock mass discontinuity. Firstly,the weak discontinuity is classified into 5 levels according to the engineering characteristics,such as the lithology,roughness,fillings and water abundance. Secondly,based on the classification of rock mass discontinuity,the in-situ shear test results under the similar conditions of structure and lithological combination are adopted as basic data,which are revised according to difference of discontinuity levels and the construction disturbance so as to determine the shear strength of discontinuity at the specific project. The revised factors include fillings,fluctuation and roughness,compressive strength and weathering,water saturation degree,blasting(or vibration). The practicality of the method is confirmed by applying on the bedding rock slope of one expressway in Chongqing. The new method is practical and easy to spread in determining shear strength of rock mass discontinuity.