Research On Shear Creep Experiment Of Swelling Rock Under Different Expansivecondition

With the domestic large-scale projects constructed in recent years, a lot of swelling rock engineering problems emerge, particularly, the long-term stability of swelling rock engineering projects related to their long-term operation and safety, and the creep having an important impact on the long-term stability of swelling rock engineering. In a lot of swelling rock engineering examples,it is found that swelling rock creep characteristics is more remarkable under swelling effect, adversely affecting long-term stability and security of the project. However, the experiments on the swelling rock creep characteristics in expansive condition are conducted, which will provide theoretical support for the long-term stability of swelling rock engineering.Experiments on shear creep characteristics of the swelling rock in different expansive state are carried out, including creep tests without expanding, completely coupling tests between swelling and creep, incompletely coupling tests between swelling and creep and separately coupling tests between swelling and creep. Based on experiments of the swelling rock long-term strength, the conclusions are founded as follows: 1It is similar between creep curves of the coupling tests between swelling and creep and that without expansive tests that when the shear stress is small, decelerating creep emerges, and when it is large, accelerating creep displays. The creep is more remarkable with expansion which is promoted by the creep.2Swelling and creep Coupling type affects the long-term strength. The long-term strength with expansion is much smaller than it without expansion, and the long-term strength under fully coupling between swelling and creep is smaller than it under separately coupling between swelling and creep.3As for swelling rock under fully coupling between swelling and creep, when normal stress is less than swelling force, the exponential function y=14.734e00076x made by carve fitting is used to express relationships between long-term strength and normal stress, otherwise the function is y=0.26x+76.667. As for swelling rock under separately coupling between swelling and creep, when normal pre-stress is less than swelling force, function y xtan(0.0002x+0.2835)+0.0617x+28.2is used to express relationships between normal pre-stress and long-term strength relationships, otherwise the function is y=xtan20.3°+80.5.4As for swelling rock under separately coupling between swelling and creep, when normal pre-stress is less than swelling force, function y=xtan(0.0002x+0.2835)+0.0617x+28.2is used to express relationships between normal pre-stress and long-term strength relationships, As for swelling rock under separately coupling between swelling and creep, when normal pre-stress is less than swelling force, function y=xtan(0.0002x+0.2835)+0.0617x+28.2is used to express relationships between normal pre-stress and long-term strength relationships, otherwise the function is y=xtan20.3°+80.5.