考虑渗流作用的锚杆支护巷道围岩稳定性分析
Stability Analysis of Surrounding Rock of Bolt Supporting Roadway Considering Seepage
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摘要: 为研究渗流作用下锚杆支护巷道的稳定性,应用等效分析方法,将锚杆的支护效果考虑成作用于锚固体两侧的1组夹紧力和强化围岩参数作用,并将渗流场转化为1组均匀分布在围岩中的一维径向体积力,同时考虑锚杆支护作用与渗流作用对围岩的影响,应用弹塑性理论,推导出了巷道围岩应力分布,得出了渗流作用下锚固体与围岩协调变形的塑性区半径方程,最后提出了围岩稳定性评价方法。结果表明:通过算例,对比分析了不考虑渗流作用和考虑渗流作用下,锚杆支护参数对围岩稳定性的影响;在相同的条件下,考虑渗流作用时需要锚杆提供更大的支护力。Abstract: To study the stability of bolt support roadway under seepage field, using the equivalent analysis method, the support effect of the bolt is considered as a set of clamping force acting on both sides of the anchor and the strengthening parameters of the surrounding rock. What’s more, the seepage field is transformed into a set of one-dimensional radial volume force uniformly distributed in the surrounding rock. At the same time, the effects of bolt support and seepage on surrounding rock are considered. Based on the elastoplastic theory, the stress distribution of the surrounding rock of the roadway is derived, and the radius equation of the plastic zone of the coordinated deformation of the anchor and the surrounding rock under the seepage is obtained. Finally, the evaluation method of the surrounding rock stability is proposed. The results show that the influence of bolt support parameters on the stability of surrounding rock under the effect of seepage and without seepage is compared and analyzed by numerical examples. Under the same conditions, the bolt is required to provide greater support when seepage is considered.