摘要
技施阶段高-超高地应力区地下洞室围岩分类对定性和定量分析评价围岩稳定性、指导现场设计、施工及支护至关重要.本文以HC法为基础岩体质量基本判据,以新生裂隙、爆破预裂一周后开挖面的残孔率、岩爆破坏深度、岩爆特征等现场可直接获取的定性或定量资料作为修正判据,提出了超高地应力条件下,脆性硬质岩的围岩分类地应力影响修正因素评分表(双江口修正表)、考虑地应力修正的围岩分类判定表(双江口法)和围岩分类步骤.实践证明,双江口法能够提高(超)高应力区脆性硬质岩的围岩分类判定的准确性,可以为支护设计提供更加准确的依据,对其他类似工程有一定的借鉴意义.
Abstract
In the technical construction stage,the classification of surrounding rock of underground caverns in high to super high ground stress areas is crucial to the qualitative and quantitative analysis and evaluation of the stability of surrounding rock,guidance for site design,construction and support.This paper takes the HC method as the basic criterion of rock mass quality,and takes the qualitative or quantitative data directly available on the site,such as the rate of residual holes in the excavation face,the depth of rock burst damage,and the characteristics of rock burst,as the correction criteria,Under the condition of ultra-high ground stress,the surrounding rock classification of brittle hard rock,crustal stress influence correction factor score table(Shuangjiangkou correction table),surrounding rock classification judgment table considering crustal stress correction(Shuangjiangkou method)and surrounding rock classification steps are proposed.Practice has proven that the Shuangjiangkou method can improve the accuracy of surrounding rock classification for brittle hard rocks in high or super high stress areas,and can provide a more accurate basis for support design,which has certain reference significance for other similar projects.
基金项目
中国电建集团核心攻关项目(DJ-HXGG-2023-04)