关键词: 循环加卸载　, 岩石　, 能量　, 弹性模量　, 变应力下限　, 残余应变

Abstract: In the context of intense summer rainfall and solar exposure,open-pit slope rock masses are subjected to the combined effects of mining-induced disturbance and alternating wetting-drying cycles,making the mechanical properties of the rock mass crucial for slope stability.To investigate this,dolomite specimens were subjected,through triaxial staged cyclic load ing-unloading tests under different lower stress limits,the peak strength,elastic modulus,residual strain,and energy dissipation behavior of dolomite were analyzed.The results indicate that both the number of wetting-drying cycles and the lower stress limit significantly influence the mechanical properties of dolomite.Under a low lower stress limit,dolomite exhibits enhanced elastic modulus and peak strength,with an approximately 10.2% increase in strength after cyclic loading.Under the combined effects of a high lower stress limit and multiple wetting-drying cycles,the elastic modulus of the rock decreases,while residual strain and cumulative dissipated energy increase markedly,indicating accelerated microcrack propagation and significant structural damage within the rock under cyclic loading.These findings provide theoretical guidance for understanding rock mass deteriora tion mechanisms and ensuring long-term stability in open-pit mining environments.

Key words: cyclicloadingandunloading,rock,energy,elasticitymodulus,lower limit of variablestress,residual strain