侧限条件下断层破碎岩体变形及渗流侵蚀特性  

Deformations and seepage-induced erosion of fractured rocks in fault under confined settings

作　　者：孙文斌 田殿金[2] 马诚 薛彦超 杨灿 朱开鹏 SUN Wenbin;TIAN Dianjin;MA Cheng;XUE Yanchao;YANG Can;ZHU Kaipeng(Shaanxi Key Laboratory of Prevention and Control Technology for Coal Mine Water Hazard,Xi’an 710077,China;College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China)

机构地区：[1]陕西省煤矿水害防治技术重点实验室,陕西西安710077 [2]山东科技大学能源与矿业工程学院,山东青岛266590

出　　处：《煤田地质与勘探》2025年第1期193-203,共11页Coal Geology & Exploration

基　　金：陕西省煤矿水害防治技术重点实验室开放基金项目(2021SKZD02);国家自然科学基金面上项目(52274131);泰山学者工程专项经费项目(tsqn202211152)。

摘　　要：【目的】我国大部分矿区进入深部开采阶段,复杂的深部水文地质条件和显著增加的隐蔽致灾因素以及断层的存在加大了矿井突水事故的风险。【方法】利用破碎岩石变形–渗流试验系统,研究断层破碎岩体的承压变形与渗流侵蚀特性,通过分析侧限轴向压缩条件下级配组合、饱水状态和渗透水压3个因素对破碎岩体变形-渗流特性的影响,进一步研究破碎岩体岩样颗粒流失特征、空隙结构及渗透参数变化的时变规律。【结果和结论】结果表明:(1)破碎岩样峰值应变随着级配指数n的增加而增大。饱水状态下相同级配的岩样在相同应力下的应变增量值比干燥状态下大。(2)流失颗粒质量与时间的拟合曲线呈指数增长函数关系,流失颗粒质量与侧限轴向应力成反比。次生颗粒质量随着轴向荷载的增大而增大。(3)岩样空隙率的演变趋势与其粒径级配密切相关。级配指数n与岩样的整体空隙率呈正相关关系。加载渗透前后相比,分形维数D与n成反比,细小粒径颗粒的质量增加,大粒径颗粒的质量降低。加载渗透后的岩样分形维数有较大的增量。(4)断层内承压水导升过程宏观上可分为承压水导升初期、导水溃砂通道扩展和发育成熟阶段,细观上可分为岩体浸水软化、错位挤压、变形开裂、破碎剥离的发育过程。研究成果可为断层突水灾害演化规律研究提供试验数据和理论依据。[Objective]Most of the mining areas in China have entered the deep mining stage.In this case,the risks of mine water inrushes increase significantly due to the complex deep hydrogeological conditions,a significant increase in the number of hidden disaster-causing factors,and the existence of faults.[Methods]Using a deformation-seepage ex-periment system for fractured rocks,this study investigated the characteristics of compressive deformations and seepage-induced erosion of fractured rocks in faults.By analyzing the impacts of particle-size distribution combinations,satura-tion state,and seepage pressure,on the deformation-permeability characteristics of fractured rocks under confined axial compression,this study investigated the time-varying patterns of changes in the particle erosion characteristics,void structure,and seepage parameters of the fractured rock samples.[Results and Conclusions]The results indicate that the peak strain of the fractured rock samples increased with an increase in the Talbot index(n).For samples with the same particle size distribution,those in the water-saturated state exhibited higher incremental strain than those in the dry state.The fitted curves of the lost mass of particles exhibited an exponential growth function with time,with the lost mass being inversely proportional to the confining axial stress.Meanwhile,the mass of secondary particles increased with the axial load.The evolutionary trend of the void rate of the rock samples was closely related to their particle size distribu-tions,with the Talbot index(n)correlating positively with the overall void rate of the samples.Comparison before and after loading and seepage revealed that the fractal dimension(D)was inversely proportional to the value of n and the masses of fine and coarse particles increased and decreased,respectively.Furthermore,the fractal dimension of the rock samples increased significantly after loading and seepage.Macroscopically,the confined water lift within faults can be divided into the initial stage of w

关 键 词：断层破碎带 颗粒流失 空隙结构 分形特征 变形规律 断层突水 

分 类 号：TD745[矿业工程—矿井通风与安全]