软岩巷道锚注支护时机优化研究

锚注支护技术是维护软岩巷道围岩稳定的一种有效方式，支护时机的选择对巷道支护效果具有很大的影响。根据对破裂软岩注浆加固后的力学特性分析，运用FLAC2D软件的应变软化本构模型，对软岩巷道最佳锚注支护时机进行了数值模拟优化分析，结果表明：随着注浆时机的滞后，浆液在围岩中的流动渗透范围逐渐增大，但注浆加固后的围岩强度却逐渐降低，巷道围岩变形表现出“先减小、后增大”的趋势。据此，提出了一种综合运用数值模拟优化和现场监测确定巷道最佳锚注支护时机的方法，并应用于工程实践，取得了良好的效果。研究成果对软岩巷道锚注支护施工和设计具有指导意义

Optimization of bolt-grouting time for soft rock roadway

Bolt-grouting technology is an effective way to maintain the stability of soft rock roadway,and its effects rely heavily on the grouting time.The mechanical characteristics of ruptured soft rock reinforced by grouting are analyzed,and the rational grouting time for soft rock roadway is optimized by numerical simulation using the strain softening constitutive law in FLAC2D.The results show that as the grouting time lags,the infiltration scope of the grout in rock increases gradually but the strength of rock reinforced by grouting decreases dramatically,and the deformation of roadway decreases first and then increases.On the basis of this,a method integrating numerical simulation and monitoring for determining the rational bolt-grouting time is proposed and better results have been achieved in engineering practice.This method provides a favorable guidance for the construction and design of bolt-grouting support in soft rock roadway.