条带充填坚硬顶板与充填体组合系统力学特性试验研究  

Study on mechanical characteristics of composite system of hard roof and filling body under strip filling

作　　者：陈绍杰[1] 尹大伟[1] 胡炳南[2] 杨惠三 尹希文[2,3] CHEN Shaojie;YIN Dawei;HU Bingnan;YANG Huisan;YIN Xiwen(State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Provence and the Ministry of Science and Technology,Sha ndong University of Science and Technology,Qingdao,Shandong 266590,China;Coal Mining Branch,Beijing 100013,China;Coal Mining and Designing Deportment,Tiandi Science and Technology Co Ltd,Beijing 100013,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 [2]煤炭科学研究总院,北京100013 [3]天地科技股份有限公司开采设计事业部,北京100013

出　　处：《采矿与安全工程学报》2020年第1期110-117,共8页Journal of Mining & Safety Engineering

基　　金：国家重点研发计划项目(2018YFC0604704);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)。

摘　　要：为研究条带充填坚硬顶板-充填体组合系统的力学特性,进行了粗砂岩-充填体组合体试样单轴压缩试验,结合组合体试样压缩破坏力学模型(将粗砂岩抽象为弹簧体),研究了其强度及破坏特征。结果表明:组合体试样的单轴抗压强度、弹性模量和峰值应变均大于单一充填体试样而小于单一粗砂岩试样;组合体试样的整体强度不仅仅是由其内部充填体强度决定的,更重要的是受到粗砂岩与充填体相互作用的影响,粗砂岩压缩变形减小了轴向应力对主要承载体-充填体的损伤作用,相当于提升了其强度,从而增大了组合体试样的整体强度,较充填体强度增大了38.27%;粗砂岩回弹变形加剧了充填体进一步破裂和破坏,在一定程度上削弱了其强度,进而降低了组合体试样的整体强度,但在回弹变形前粗砂岩已发生压缩变形而适应了轴向应力的增加,因此该强度削弱作用是有限的;组合体试样的破坏主要发生在充填体内,主要以张拉破坏为主,伴随着局部剪切和剥落破坏,而粗砂岩未发现明显破坏。In order to study mechanical characteristics of composite system of hard roof and filling body under strip filling, uniaxial compression tests are conducted on composite samples of coarse sandstone and filling body. Combining with compression failure mechanics model for composite sample(coarse sandstone being abstracted into a spring body), the strength characteristics and failure mechanisms of composite samples are analyzed. Results show that uniaxial compressive strengths, elastic moduli and peak strains of composite samples are larger than those of single filling-body samples, but smaller than those of single coarse sandstone samples. The overall strength of composite sample is not only determined by filling body strength. Meanwhile, it is also affected by interactions between coarse sandstone and filling body. Compression deformation of coarse sandstone reduces damage effect of uniaxial stress on main bearing body of filling section, which is equivalent to enhancing its strength. Therefore, the overall strength of composite sample increases, which is 38.27% higher than that of filling body. Rebound deformation of coarse sandstone caused by filling body fracturing aggravates the further fracture and failure of filling body, to a certain extent, reducing its strength. As a result, the overall strength of composite sample decreases. However, this strength weakening effect is limited due to that the coarse sandstone has undergone compression deformation before rebound deformation, which adapts to increase in uniaxial stress. Composite sample failure mainly occurs in filling body, which mostly is tensile failure accompanying by local shear and surface spalling failures. Meanwhile, no obvious damage is found in coarse sandstone.

关 键 词：坚硬顶板-充填体系统 力学特性 粗砂岩-充填体相互作用 回弹变形 破坏特征 

分 类 号：TD32[矿业工程—矿井建设]