预应力损失对高预应力全锚索支护技术的影响

Influence of Pre-stress Lose on Anchored Cable Supporting with High Pre-stress

摘要: 针对余吾煤业全断面强力锚索支护技术应用中预应力损失问题,借助有限差分数值计算程序FLAC,模拟研究了不同锚索预应力下围岩应力分布特征和支护效果,探讨了影响预应力损失因素。依据井下具体工程环境,统计分析了预应力损失范围一般为20%～25%,提出采用超张拉25%弥补预应力损失,并在井下全断面强力锚索支护中应用试验。实践结果表明:预应力的损失严重减弱了全断面强力锚索支护效果,采用超张拉技术后,设计的支护方案能有效地控制围岩变形。

Abstract: For the problem of pre-stress lose of whole-section consolidated anchored cable supporting in Yuwu Coal,applying FLAC to simulating stress distribution characteristic and supporting effect under different pre-stresses of anchored cable.Pre-stress lose was usually 20%-25%.It was put forward that pre-stress was compensated by super tension 25%.Underground practice showed that pre-stress lose seriously weakened whole-section consolidated anchored cable supporting effect and super tension technology could effectively control deformation of surrounding rock.