School of Mechanics and Photoelectric Physics, Anhui University of Science and Technology
School of Civil Engineering and Architecture, Anhui University of Science and Technology

为研究地下岩体巷道开挖后在复杂地应力作用下巷道围岩的蠕变效应,利用自主研发的相似模拟试验装置对由相似材料制作的模型进行循环加卸载。实验结果表明:在经历长期分级循环加卸载,模型在抗压强度的80%时发生了显著的巷道下沉现象,相比较巷道的半径下沉了1.8%;围岩应变随时间呈现蠕变特性,经历了瞬时应变、稳态应变、滞后弹性恢复应变及残余应变等多个阶段;随着载荷逐级增加,应变值和弹性恢复应变均呈上升趋势,但每级应变增量逐渐减小,反映了材料由弹性变形向塑性变形的过渡,显示出一定程度的永久变形;各点的体积应变趋势大致与其应变的变化趋势相同;由于载荷的施加改变了围岩的原始应力状态,产生了应力集中,在长时间的循环加卸载导致围岩发生蠕变,促使裂缝的出现及扩展。此外,裂缝的形成和发展进一步加剧了巷道的变形,导致巷道整体下沉,形状变得不规则。

In order to study the creep effect of roadway excavation in underground rock mass under complex ground stress, the model made of similar materials was loaded and unloaded. The results show that, after a long period of graded cyclic loading and unloading, the roadway subsidence occurs at 80% of the compressive strength of the model, and the radius of the roadway decreases by 1. 8%. The strain of surrounding rock exhibits creep characteristics with time, experiencing stages of instantaneous strain, steady strain, hysteretic elastic recovery strain and residual strain. With increasing the load step by step, the strain value and elastic recovery strain both increase, but the increment of strain at each stage gradually decreases, reflecting the transition from elastic deformation to plastic deformation, showing a certain degree of permanent deformation. The trend of volume strain at each point is roughly the same as that of strain variation. Due to the application of load, the original stress state of surrounding rock is changed, resulting in stress concentration, and the creep of surrounding rock is caused by long-term cyclic loading and unloading, which promotes the emergence and expansion of cracks. In addition, the formation and development of cracks further aggravates the deformation of the roadway, resulting in the overall subsidence of the roadway and its shape becoming irregular.

国家自然科学基金资助项目(52074006,51404011)

卢小雨,张博文,董春亮,等.深部巷道围岩循环加卸载蠕变特性的相似模拟试验研究[J].煤炭工程,2025,57(1):129-136.