深部多形式应用交岔点围岩失稳机理及能量演化研究

Instability mechanism and energy evolution of surrounding rock at intersections of deep multi-form application

随着采矿进入深部地层,具有长服务年限的各类巷道交岔点围岩发生强烈破坏,需要明晰深部环境下交岔点围岩失效机理,以针对性地指导修复和补强作业。通过对多地矿井交岔点维护情况的调研,全面总结了连接型、交岔型、分岔型和旋岔型(环三角柱)四类16种交岔点类型,提出了三类交岔点的典型应用形式:单一大型交岔点、嵌套式两交岔点组和环三角岩柱式交岔点群。将现场交岔点的破坏情况分为围岩局部破坏、三角岩柱破坏和整体性破坏的三种级别,从灾害的诱因和来源上,提出了外部环境因素、自身结构属性和人为设计隐患的三类13种致灾因素,并详述了各种致灾因素的致灾路径。建立了三类典型应用形式下交岔点的精细化模型,对数值软件进行二次开发,引入了畸变能密度指标进行围岩的能量分析。研究表明,交岔点围岩的畸变能峰值在三角区岩柱内,增高系数在2.5左右。最大断面处围岩畸变能同样发生积聚,增高系数在1.5左右。因此,提出了交岔点的修复需以强化三角岩柱和大断面处围岩为重点,并对深井交岔点的修复提出了以三角岩柱和大断面段补强为主的针对性方案。本研究为深部交岔点的破坏因素分析、数值模拟指标引入和修复支护提供了参考。

As mining progresses into deep strata,severe damage occurs at various long-life roadway intersections.To guide targeted repair and reinforcement operations,it is necessary to investigate the failure mechanism of surrounding rock at intersections in deep environments.Four categories and 16 types of intersections of connection type,interleaving type,bifurcation type,and rotary type(ring triangular column)are comprehensively summarized by investigating the maintenance of intersections in many mines.Three types of typical application forms of intersection points are proposed:a single large-scale intersection point,two intersection points for nested combined application,and an intersection point group for ring triangular rock column application.The failure of intersections on site is divided into three levels:local damage to the surrounding rock,damage to the triangular rock column,and overall damage.Three categories of 13 disaster-causing factors of external environmental factors,their structural attributes,and artificial design hidden hazards are proposed from the initiation and cause of the disaster,and the disaster-causing paths of various disaster-causing factors are described in detail.The refined intersection models under three application forms are established,and the secondary development of numerical software is carried out to introduce the distortion energy density index to analyze the energy of the surrounding rock.Studies have shown that the surrounding rock distortion energy peak at intersections is in the triangular rock column,and the increase coefficient is about 2.5.Meanwhile,the distortion energy of the surrounding rock also accumulates at the maximum section,and its increase coefficient is about 1.5.Therefore,it is proposed that the repair of the intersection should focus on the reinforcement of the triangular rock column and surrounding rock at the large cross-section,and a targeted plan is proposed for the repair of the intersections of the deep mine,focusing mainly on the reinforcement of the triangular rock column and the large cross-section.This study provides a reference for the analysis of failure factors,the introduction of numerical simulation indicators,and the repair support of deep intersections.