Abstract:For acquiring the shear strength of cementation plane of south anchor of Runyang Suspension Bridge over the Yangtze River,and on the basis of fractal geometry theory and from undulation angle of rock mass¢s structural plane,a new method called angle of root mean square slope method(ARMSS) is proposed to calculate fractal dimensions of contours of cementation plane. Furthermore,the relationship between fractal dimension and roughness coefficient is given. From tests of shear strength of two-phase rough cementation planes,the influences of two-phase roughness coefficient on its shear strength,shear deformation behavior and shear failure mechanism are discussed. The research results can provide a theory foundation for friction structure design of anchors of Runyang Suspension Bridge.