Abstract：For the purpose of jointed rock mass excavation effect simulation，conventional triaxial test and stress control test of increasing axial pressure and unloading confining pressure of limestone containing natural joint have been performed；and the complete stress-strain curves were gained. The analytical results of fracture features of rocks，strength and deformation characteristics show that failure modes of the specimens can be classified into two types；one is shearing failure across the joint plane and the other is sliding failure along the joint plane whether the conventional triaxial test is or the stress control test of increasing axial pressure is. Conventional triaxial test shows that the specimen is shearing failure across the joint plane when the angle between the joint plane and the maximum principal stress is less than 40°；and the specimen is sliding failure along the joint plane when the angle is greater than 40°. But above two failure modes of loading and unloading test is not interrelated to the angle between the joint plane and the maximum principal stress. The peak strength，strength of sliding failure along the joint plane obviously less than that of shearing failure across the joint plane under loading and unloading condition. The failure specimens of sliding failure along the joint plane have not obvious yield stage；and the strength suddenly decreases after the peak strength；the yield and strength increase process don¢t exist compared to conventional triaxial test.
王在泉，张黎明，孙辉. 含天然节理灰岩加、卸荷力学特性试验研究[J]. 岩石力学与工程学报, 2010, 29(S1): 3308-3313.
WANG Zaiquan，ZHANG Liming，SUN Hui. EXPERIMENTAL RESEARCH ON MECHANICAL PROPERTIES OF LIMESTONE CONTAINING NATURAL JOINTS UNDER LOADING AND UNLOADING CONDITIONS. , 2010, 29(S1): 3308-3313.
