破碎矸石干湿循环长期承载变形及分形特征  

Experimental study on long-term load-bearing deformation and fractal characteristics of crushed gangue under dry-wet cycles

作　　者：江宁[1] 尹大伟[1] 杨永杰[1] 马俊彪 葛尧 JIANG Ning;YIN Dawei;YANG Yongjie;MA Junbiao;GE Yao(State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Provence and the Ministry of Science and Technology,Shandong University of Science and Technology,Qingdao,Shandong 266590,China)

机构地区：[1]山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地,山东青岛266590

出　　处：《采矿与安全工程学报》2020年第1期176-182,共7页Journal of Mining & Safety Engineering

基　　金：国家重点研发计划项目(2018YFC0604705);国家自然科学基金项目(51904167,51774194);山东省自然科学杰出青年基金项目(JQ201612);山东省自然科学基金项目(ZR2017MEE055);山东科技大学人才引进科研启动基金项目(2019RCJJ019)。

摘　　要：为研究采空区矸石充填体干湿循环长期承载特性,运用自主研制的大尺寸破碎岩石变形-渗流试验系统,进行了破碎矸石干湿循环蠕变试验,分析了矸石岩性、轴向应力及粒径级配对破碎矸石干湿循环长期承载变形特性及分形特征的影响。结果表明:在相同轴向应力和粒径级配条件下,随岩石单轴抗压强度的增大,破碎岩石试样的碎胀系数增大,而应变、蠕变阶段的应变和碎胀系数及分形维数减小;在相同粒径级配条件下,随轴向应力的增大,破碎矸石相邻两级荷载的应变差和碎胀系数差逐渐减小,而分形维数逐渐增大;当n(Talbol幂指数)为0.5时,破碎矸石蠕变变形、压实特征值最小,n为0.3次之,而当n为0.7时最大;同时随n的逐渐增大,破碎矸石压缩后分形维数增量增大,更多的矸石颗粒被压碎。In order to study long-term load-bearing characteristics of gangue filling body in goaf under dry-wet cycles, creep test of crushed gangue was conducted by adopting self-developed large-scale deformation-seepage test system of crushed rocks. Effects of gangue lithology, axial load and particle size ratio on long-term bearing deformation, compaction and fractal characteristics of crushed gangue were investigated. Results show that under same axial stress, the higher the strength of gangue is, after compression, the smaller the creep deformation eigenvalues(compression quantity and strain), compaction eigenvalues(residual dilatancy coefficient and voidage) and fractal dimension are. Meanwhile, creep deformation eigenvalues and compaction eigenvalues decrease with the increase in wet-dry cycles. With the increasing axial stress, creep deformation eigenvalues and compaction eigenvalues of crushed gangue decrease gradually, while fractal dimension increases gradually after compression. Creep deformation eigenvalues of each wet-dry cycle decrease with the increase in wet-dry cycles. When n(Talbol power index) being 0.5, creep deformation eigenvalues and compaction eigenvalues of crushed gangue are the smallest, followed by the value when n being 0.7. However, creep deformation eigenvalues and compaction eigenvalues are the largest. At the same time, with the gradual increase in n, fractal dimension of crushed gangue after compression is larger. The fragmentation degree is higher.

关 键 词：破碎矸石 干湿循环 蠕变应变 压实特征 分形维数 

分 类 号：TD325[矿业工程—矿井建设]