EFFECT OF CRACK-STOPPING HOLE ON SHEAR FRACTURE OF ROCK
会议名称：《The 7th International Symposium on Rockburst and Seismicity in Mines(RaSiM7)》
会议日期：2009年
学科分类：08[工学] 080104[工学-工程力学] 0815[工学-水利工程] 0801[工学-力学（可授工学、理学学位）]
基 金：The financial supports from the National Natural Science Foundation of China(Grant No.50374073) the Natural Science Foundation of Hunan Province,China(Grant No.08JJ3119)
摘 要：Effect of crack-stopping hole on shear(ModeⅡ) fracture of rock is studied numerically and *** element method through the displacement approach is used to calculate the shear stress intensity factors of the specimens with and without symmetrical double holes,Kand K Shear-box test and new electrometric method with conductive glue are adopted to measure the maximum shear stress intensity factor(K),stable shear crack propagation rate(V) and time(T) of these specimens in order to find out optimal double holes for shear crack-stopping. Results show that the effect of crack-stopping hole on shear fracture of rock specimen depends on its location and size,which can be denoted by a regression equation about the ratio of K/K and the three parameters, radius(R),distance away from the notch tip(L) and distance between the two holes(S).The more the R and L,the larger the K/K and the easier to fracture the rock ***,the more the 5,the smaller the K/K and the more difficult to propagate the shear *** R and L are the smallest and S is the largest,the specimen with double holes has the largest values of K and T and the smallest value of V,which is most favourable to shear crack-preventing. Adding optimal double holes symmetrical with respect to the original crack plane is an effective method for shear crack arresting of brittle rock.