中文摘要：

通过对岩石加载-蠕变-卸载的能量转换与变形机制分析，利用RLW-2000型岩石三轴流变仪，对2组岩石进行单轴分级加载蠕变试验，分析岩石不同应变差值下能量的耗散过程，确定岩石不同加载水平f或循环次数）与变形模量的关系，研究加载蠕变与应力卸载的曲线路径。结果表明：岩石分级加载蠕变的能量转换可分为加载应变与蠕变应变2个部分，随着每一级载荷作用下应变差的增加，岩石塑性应变能与耗散能呈非线性增加趋势，且塑性应变能曲线与耗散能曲线的开口、应变差及岩石损耗能量也越大；在相同加载水平下，岩石塑性应变能大于耗散能，且应变差与塑性应变能、耗散能的关系可分别用二次多项式、乘幂函数进行描述；岩石变形模量随着加载水平（或循环次数）的增加而变大，表现为先突然增加较大到缓慢增加至趋于相对平缓，相同加载水平（或循环次数）下，高强度岩石变形模量大于低强度岩石变形模量；岩石加载蠕变应变与卸载应力松弛均随加载水平的提高而增大，相同加载水平下，高强度岩石蠕变应变小于低强度岩石蠕变应变，但高强度岩石应力松弛大于低强度岩石应力松弛，高强度岩石加载曲线穿越上一级载荷卸载后的应力松弛区，而低强度岩石加载曲线则穿越上一级加载水平后的蠕变应变区。

英文摘要：

Based on analysis of deformation mechanism and energy conversion in rock loading-creep-unloading, the creep tests of step uniaxial loading on two groups samples were operated by RLW- 2000 rock triaxial rheometer. The rock energy dissipation was analyzed in different strain differences, the relationship of different loading level（or cycle number） and deformation modulus were determined, and curve paths of loading creep and unloading stress were studied. The results showed that energy conversion had two parts of loading strain and creep one in step-loading rock creep. With strain difference of every loading increasing, rock plastic strain and dissipation energy increased nonlinearly, and the opens, strain differences and loss rock energy of plastic strain and dissipation energy curves increased. In same loading, rock plastic strain energy was larger than dissipation one, and the relationships of strain difference and plastic strain energy, dissipation one, can be described by quadratic polynomial and power function respectively. Rock deformation modulus increased from abruptly to slowly, and then relative gently with loading level（or cycle number） increasing, and deformation modulus of the higher-strength rock was larger than the lower one in same loading level（or cycle number）. Rock loading creep strain and unload stress relaxation increased with loading level increasing, the creep strain in higher-strength rock was less than the lower and stress relaxation went by contrary in same loading level. Loading curve of the higher-strength rock was cross the stress relaxation zone of last step unloading, and the lower one cross the creep strain zone.