为研究锚固螺栓不同紧固扭矩对弹性分开式扣件板下弹性垫板静刚度的影响,以我国地铁常用的DZIII型扣件为研究对象,计算锚固螺栓在不同紧固扭矩作用下对板下弹性垫板的初始预压力,并对TPEE和橡胶类板下弹性垫板在不同初始预压力作用下的...为研究锚固螺栓不同紧固扭矩对弹性分开式扣件板下弹性垫板静刚度的影响,以我国地铁常用的DZIII型扣件为研究对象,计算锚固螺栓在不同紧固扭矩作用下对板下弹性垫板的初始预压力,并对TPEE和橡胶类板下弹性垫板在不同初始预压力作用下的静刚度进行测试和评价。结果表明:锚固螺栓紧固扭矩为150,200,250 N·m时,板下弹性垫板的初始预压力为69.94,93.24,116.54 k N;板下弹性垫板静刚度测试结果同静刚度测试荷载取值范围密切相关,且同初始预压力呈正相关关系;板下弹性垫板静刚度应根据扣件系统正常服役状态下锚固螺栓紧固扭矩引起的初始预压力进行测试和评价。展开更多
Axial compression stress, produced by the pre-tightening force of a bolt, is a necessary condition for surrounding rock to form a whole structure. For this study, we built a mechanical model for an end-anchorage bolt,...Axial compression stress, produced by the pre-tightening force of a bolt, is a necessary condition for surrounding rock to form a whole structure. For this study, we built a mechanical model for an end-anchorage bolt, which represented the effect of a bolt on the surrounding rock in roadways in order to obtain its elastic solution. Simultaneously, we analyzed factors affecting the axial compression of the bolt on the surrounding rock and obtained the axial stress contours of the anchorage area through this elastic solution. The results indicate that 1) the axial compression stress in the anchorage area is proportional to the pre-tightening force and confirms the rule that stress declines sharply with the increase in axial distance from the bolt, with an effective stress radius of 1 m; 2) the maximum axial compression stress declines first and then rises with the increase in depth from the surface of the anchorage surrounding rock and 3) the size of the axial compression area is mainly determined by the length of the bolt.展开更多
Based on the characteristics of surrounding rocks for deeply inclined roadway affected by argillation and water seepage, a structure model of layer crack plate was established to analyze the shear sliding instability ...Based on the characteristics of surrounding rocks for deeply inclined roadway affected by argillation and water seepage, a structure model of layer crack plate was established to analyze the shear sliding instability mechanism. Through solid mechanics analysis of anchored surrounding rock with defect from water seepage, combined with numerical analysis for instability mechanism under water seepage in deeply inclined roadway, key factors were proposed. Results show that with increasing height of layer crack plate, lateral buckling critical load value for high wall of the roadway decreases; there is a multistage distribution for tensile stress along the anchor bolt with defect under pulling state condition;groundwater seepage seriously affects the strength of surrounding rock of the roadway, to some extent the plastic zone of the high side rises up to 8 m. Finally some support strategies were proposed for the inclined roadway and successfully applied to Haoyuan coal mine in Tiela mining area,western China.展开更多
文摘为研究锚固螺栓不同紧固扭矩对弹性分开式扣件板下弹性垫板静刚度的影响,以我国地铁常用的DZIII型扣件为研究对象,计算锚固螺栓在不同紧固扭矩作用下对板下弹性垫板的初始预压力,并对TPEE和橡胶类板下弹性垫板在不同初始预压力作用下的静刚度进行测试和评价。结果表明:锚固螺栓紧固扭矩为150,200,250 N·m时,板下弹性垫板的初始预压力为69.94,93.24,116.54 k N;板下弹性垫板静刚度测试结果同静刚度测试荷载取值范围密切相关,且同初始预压力呈正相关关系;板下弹性垫板静刚度应根据扣件系统正常服役状态下锚固螺栓紧固扭矩引起的初始预压力进行测试和评价。
基金Projects are the National Basic Research Program of China (No.2007CB209400)the 111 Project (No.B07028)the National Natural Science Foundation of China (Nos.50634050 and 50904065)
文摘Axial compression stress, produced by the pre-tightening force of a bolt, is a necessary condition for surrounding rock to form a whole structure. For this study, we built a mechanical model for an end-anchorage bolt, which represented the effect of a bolt on the surrounding rock in roadways in order to obtain its elastic solution. Simultaneously, we analyzed factors affecting the axial compression of the bolt on the surrounding rock and obtained the axial stress contours of the anchorage area through this elastic solution. The results indicate that 1) the axial compression stress in the anchorage area is proportional to the pre-tightening force and confirms the rule that stress declines sharply with the increase in axial distance from the bolt, with an effective stress radius of 1 m; 2) the maximum axial compression stress declines first and then rises with the increase in depth from the surface of the anchorage surrounding rock and 3) the size of the axial compression area is mainly determined by the length of the bolt.
基金provided by the Natural Science Foundation of Jiangsu Province(No.BK20141130)the Fundamental Research Funds for the Central Universities(Nos.2014QNB27 and 2010QNB22)
文摘Based on the characteristics of surrounding rocks for deeply inclined roadway affected by argillation and water seepage, a structure model of layer crack plate was established to analyze the shear sliding instability mechanism. Through solid mechanics analysis of anchored surrounding rock with defect from water seepage, combined with numerical analysis for instability mechanism under water seepage in deeply inclined roadway, key factors were proposed. Results show that with increasing height of layer crack plate, lateral buckling critical load value for high wall of the roadway decreases; there is a multistage distribution for tensile stress along the anchor bolt with defect under pulling state condition;groundwater seepage seriously affects the strength of surrounding rock of the roadway, to some extent the plastic zone of the high side rises up to 8 m. Finally some support strategies were proposed for the inclined roadway and successfully applied to Haoyuan coal mine in Tiela mining area,western China.