全长锚固预应力锚杆杆体受力特征分析  

The mechanical characteristics analysis of fully anchored pre-stressed bolts in coal mines

作　　者：李冲[1] 徐金海[1] 李明[2] 

机构地区：[1]中国矿业大学矿业工程学院,深部煤炭资源开采教育部重点实验室,江苏徐州221116 [2]中国矿业大学力学与建筑工程学院,江苏徐州221116

出　　处：《采矿与安全工程学报》2013年第2期188-193,共6页Journal of Mining & Safety Engineering

基　　金：江苏高校优势学科建设工程项目;煤炭资源与安全开采国家重点实验室自主研究项目(SKLCRSM11X02)

摘　　要：采用理论分析、现场实测等研究方法,分析了锚杆杆体轴应力、剪应力与预紧力的关系以及杆体轴应力与剪应力的分布规律。结果表明:锚杆轴应力随预应力的增大而增加,在锚杆全长方向上呈曲线变化的,从锚杆尾部到锚杆端头方向,轴应力先增加后减小,在中性点处轴应力最大,轴应力最大值位置向锚杆尾端移动;随锚杆预应力增加,锚杆杆体剪应力在巷道表面与中性点位置一段减小,在中性点与锚杆端头一段增加,中性点处锚杆剪应力为零,中性点向锚杆尾部移动。全长锚固锚杆预紧力不是越大越好,而是有个合理的范围,预紧力大小要与锚杆支护系统强度相匹配。Theoretical analysis,field measurements,and other methods were used to analyze the relationship between axial stress,shear stress,and pre-load on the bolts and the distribution of the axial and shear stresses.The results show that the axial stress increases as the pre-stress increases.The axial stress shows a curve changing with the pre-stress upon moving from the bolt tail to its head,that is,the axial stress first increases and then decreases along the bolt and at the neutral point the axial stress reaches a maximum value.The maximum value of the axial stress,moves toward the bolt tail end as the pre-stress increases.The shear stress decreases between the roadway surface and the neutral point and then increases between that point and bolt end.The shear stress equals zero at the neutral point.The proper pre-load for the fully anchored bolt is not ＂the bigger the better＂.There is a reasonable range for the pre-load that should match the bolt support system strength.

关 键 词：预应力锚杆 全长预应力锚固 锚杆轴应力 锚杆剪应力 

分 类 号：TD353[矿业工程—矿井建设]