Research Of Elastic Resistance Coefficient And Its Anisotropism Of Jointed Rocks

Elastic resistance coefficient is a mechanical index to characterise the ability of rock resistance lining to direction of surrounding rock deformation, it is aslo an important mechanical parameters in tunnel support design.At present we generally do not consider the anisotropy of elastic resistance coefficient of rock in the tunnel engineering design.Experiments and practice have proved that in addition to rock deformation, damage and the communication way of stress in rock mass,the structural characteristics of rock mass is an important factors. For common jointed rock mass in engineering, the mechanical properties of surrounding rock is related to the direction due to the existence of rock mass with a large number of all kinds of joint. Therefore, the study of joints on surrounding rock elastic resistance coefficient influence law and anisotropic characteristics of joint rock mass elastic resistance coefficient has important theoretical significance and engineering guidance for the tunnel support design.This paper uses discrete element method calculation software UDEC4.0 to study the anisotropy characteristics of jointed rockmass through simulation of surrounding rock elastic resistance coefficient testing process. The paper mainly analyzes the influence of joint spacing and joint angle on surrounding rock elastic resistance coefficient and its characteristics of anisotropy of IV class soft surrounding rock with good or combination of general relatively complete.The main work and achievements are as follows:(1)to design the test scheme of calculation of surrounding rock elastic resistance coefficient by using the discrete element method.(2) to analyze the effects of 0.4m～1.0m joint spacing on the elastic resistance coefficient of IV class surrounding rock, and to investigate the variation rules of elastic resistance coefficient when changing joint spacing.(3) to analyse the effects of 30°～125° joint angle on the elastic resistance coefficient of IV class surrounding rock, and to investigate the variation rules of elastic resistance coefficient when changing joint angle.(4) to analyse the distribution of elastic resistance coefficient of jointed rocks,and to research anisotropy of elastic resistance coefficient preliminarily.