煤矿斜井管片衬砌与可压缩层联合支护的效果

为研究盾构斜井管片衬砌与可压缩层联合支护体系中可压缩层参数对管片衬砌力学性能的影响，以神华新街台格庙矿区主斜井工程为依托，建立考虑管片衬砌与可压缩层之间接触效应和管片整环刚度折减效应的数值计算模型，分析有无可压缩层、不同可压缩层刚度及厚度等因素下管片衬砌内力和变形的分布规律和变化情况；采用相似模型试验对上述问题进行了进一步研究，并对有无可压缩层时管片的极限承载力和破坏形式进行了探讨.研究结果表明:可压缩层刚度越大，管片所受围岩压力越大且分布越不均匀，同时使得管片弯矩减小，轴力增大，当可压缩层模量与围岩模量之比在0.1~0.5之间变化时更为明显；随着可压缩层厚度的增大，管片所受围岩压力依次按不均匀、均匀、不均匀的趋势变化，当可压缩层厚度与管片厚度之比为1.7时围岩压力最小，管片轴力则随可压缩层厚度的增大而减小；可压缩层存在与否对管片变形影响甚微，通过自身的挤密吸收围岩压力且促使应力重分布，从而减小并均匀化传递至管片上的荷载，使得管片内力随外荷载的增长更平缓，量值更小且分布更均匀，并使管片的极限承载力提高了40%；有无可压缩层时管片破坏均经历椭变、椭变加剧、裂缝出现和扩展、失稳破坏的过程，且有可压缩层时管片的破坏更严重. 

Combined Support of Segmental Lining and Compressible Layer of Coal Mine Shafts

In order to study the influence of the compressible layer parameters on the mechanical properties of the segmental lining in the combined support system of the inclined shaft constructed by shield, a numerical model considering the contact effect between the segmental lining and the compressible layer and the stiffness reduction of the segment ring was established based on the Main Inclined Shaft Project of Shenhua Xinjie Taigemiao Coal Mine Area, and the distribution characteristics and variation laws of the internal force and deformation of the segmental lining are analyzed under different factors such as the presence or absence, the stiffness and the thickness of compressible layer. Similar model tests were carried out to further investigate the above problems. The ultimate bearing capacity and the form of destruction are also discussed. The results show that the greater the compressible layer stiffness, the greater the and the more uneven distribution of the surrounding rock pressure on the segment, at the same time, the bending moment of the segment decreases and the axial force increases. It is more obvious when the ratio of compressible layer modulus to surrounding rock modulus varies from 0.1 to 0.5. With the increase of the compressible layer thickness, the surrounding rock pressure on the segment varies according to the trend of uneven to uniform and then again to uneven. When the ratio of the compressible layer thickness to the segment thickness is 1.7, the pressure of the surrounding rock is the smallest. The axial force decreases with the increase of compressible layer thickness. The existence of compressible layer has little effect on the deformation of segmental lining. The model test results further show that the compressible layer can absorb the surrounding rock pressure and cause stress redistribution through its own compaction, so as to reduce and homogenize the load transferred to the segment, so that the internal force of the segment grows more smoothly with the external load smaller and more evenly distributed; and increased the ultimate bearing capacity of the segments by 40%. In the presence or absence of the compressible layer, the failure of the segment has experienced the processes of elliptic, elliptical exacerbation, the occurrence and expansion of the crack and instability.Moreover, the damage of the segment is more serious when the compressible layer is present. The research results of this paper can provide some reference for the design and construction of similar projects.