Cyclic weak disturbance caused by blasting, drilling, earthquake and transport is an important factor to deep rock projects failure. In order to study the influence of cyclic weak disturbance on the stress relaxation of rock under different confining pressures, a step loading stress cyclic weak disturbance relaxation test was carried out on marble, and an impact factor of weak disturbance was defined. The test results showed that the rock peak strength was the smallest under cyclic weak disturbance relaxation; before the peak stress was reached, the relaxation magnitude of weak disturbance increased with the increase of the initial stress level; and it continuously increased with the decrease of the initial stress level after the peak stress. The stress relaxation rate nonlinearly decreased with axial strain levels; by contrast, the initial stress relaxation rate was proportional to the strain level. As the strain increased, the weak disturbance effect presented a nonlinear growth characteristic of first decreasing and then increasing.

爆破、钻孔、地震、运输等引起的周期性弱扰动是深部岩石工程失败的重要因素。为研究不同围压下循环弱扰动对岩石应力松弛的影响，对大理岩进行阶跃加载应力循环弱扰动松弛试验，定义了弱扰动的影响因子。试验结果表明，循环弱扰动松弛下岩石峰值强度最小；在达到峰值应力之前，弱扰动的弛豫幅度随着初始应力水平的增加而增加；峰值应力后随着初始应力水平的降低而不断增加。应力松弛率随轴向应变水平非线性降低；相比之下，初始应力松弛率与应变水平成正比。随着应变的增加，弱扰动效应呈现出先减小后增大的非线性增长特征。