锚杆支护参数对岩爆防治效果的影响研究

Study on the Effect of Rock Bolting Parameters on Rock Explosion Prevention

岩爆是一种严重威胁深埋地下工程施工安全的动力灾害,现有诸多岩爆判别指标,但均未考虑支护作用的影响。鉴于此,本文基于弹性应变能理论,结合锚固效应与锚杆吸能理论,提出了锚杆支护下的岩爆危险性判别准则。以草果山隧道为例,对不同锚杆支护参数下岩爆防治效果进行研究,选取锚杆间距、锚杆长度、锚杆直径和锚杆类型4个因素,在不同岩爆等级下进行正交数值模拟试验。试验结果表明:对岩爆判别准则影响大小次序依次为锚杆类型>锚杆间距>锚杆长度>锚杆直径。此外,试验结果还得出了不同岩爆等级下的锚杆支护的最优参数选择,为同类高地应力隧道支护措施设计提供了参考。

Rockburst is a dynamic disaster that seriously threatens the safety of underground constructions.There are many rockburst indexes,but none of them consider the supporting effect.This paper is based on both elastic strain energy theory and anchorage effect and bolt absorption theory.Moreover,the criterion for identifying the risk of rockburst under rock bolting is proposed.Taking the Caoguoshan tunnel as an example,the effect of rockburst prevention under different rock bolting parameters was studied.Four parameters were focused on,including bolt spacing,bolt length,bolt diameter,and bolt type.Experimental analyses were carried out under different rockburst grades,and the results show that the order of parameters􀆳impact on the rockburst criterion is bolt type>bolt spacing>bolt length>bolt diameter.In addition,the optimal parameter selection for rock bolting under different rockburst grades is obtained,which provides a reference for the design of support measures for similar highland stress tunnels.