大松动圈下锚固承载层支护效应的弹塑性解

对于大松动圈围岩巷道，锚杆和围岩共同作用在松动圈内部形成了“锚固承载层”。为研究大松动圈下“锚固承载层”对巷道围岩应力分布的影响，通过理论推导和实例分析，认为“锚固承载层”在极限平衡状态下对塑性区提供的支护强度pid]由锚杆支护强度pi]和锚固承载结构强度两部分组成，根据支护强度pi]和锚固层厚度b的关系提出了“锚固界限厚度”概念。对于松动圈外的围岩，将巷道周边的应力分布进行了重新计算并与传统的Finner-Kastner解进行了比较。研究表明：承载结构在巷道稳定性控制中占据主导作用，支护强度和承载结构协调作用更有利于巷道维护，修正Finner-Kastner解可为深部巷道围岩支护机理研究以及巷道支护参数设计提供理论依据。

Elastic-plastic Solution of the Supporting Effect about the Anchorage Bearing Layer under Large Loosing Zone

For surrounding rock of roadway under large loosing zone， the interaction of anchor and surrounding rock forms “anchor bearing layer“ within the loose zone. In order to study the influence of “anchorage bearing layer“ on stress distribution of surrounding rock in roadway under large loosing zone， it is obtained that the support strength pid] provided by “anchorage bearing layer“ in plastic zone under ultimate equilibrium state consists of two parts: bolt support strength pi] and anchorage bearing structure strength， by theoretical deduction and practical analysis. According to the relationship between support strength pi] and thickness of anchorage layer b， the concept of “anchorage limit thickness“ is proposed. For the surrounding rock outside the loosening zone， the stress distribution around the roadway can be recalculated and compared with the traditional Finner-Kastner solution. The practice shows that the bearing structure plays a dominant role in keeping the stability of roadway， and the coordination of support strength and bearing structure is more conducive to the maintenance of the roadway. Modified Finner-Kastner solution can provide some reference for understanding supporting mechanism of deep roadway，and also provide corresponding theoretical basis for supporting parameter design of roadway.