摘要
在冲击地压巷道中,冲击载荷会造成锚杆支护系统构件与围岩相互作用力急剧增加,托板在高作用力下易出现变形破坏。针对上述问题,采用微机控制电液伺服试验机和自主研发的落锤冲击试验装置,对煤矿常用的拱形托板及其组合构件等3种试样进行了力学性能测试,获取试样静载力-位移曲线、冲击力时程曲线、位移时程曲线及变形破坏特征,分析了锚杆托板及组合构件的抗冲击性能。研究结果表明:静载作用下,托板承载力位于228~243 kN,最大变形量14.10 mm,变形呈现拱高降低、四角翘起、连接部位向圆心转移等特征。动载作用下,托板变形均经历拱高降低、四角翘起及压平3个阶段,冲击能量为500~3 000 J时,冲击力时程曲线呈现急剧上升阶段、震荡作用阶段和迅速下降阶段;冲击能量为3 500~5 000J时,冲击力时程曲线呈急剧上升阶段、震荡稳载阶段、震荡上升阶段和迅速下降阶段。随着冲击能量的增加,试样的冲击力峰值均逐渐增大,与静载相比,托板试样的动载荷峰值较大。试样位移时程曲线可分为弹塑性变形和回弹变形两阶段,弹塑性变形阶段变形量与作用时间呈现线性关系,正、反向及组合构件最大形变量平均作用时间占比分别为68.66%、69.25%、66.66%;回弹变形阶段,3种试样平均弹性形变量分别为1.71、1.84、3.23 mm。整个冲击过程中,3种试样冲击能量平均转化率分别为96.82%、97.33%、93.78%。总体来看,托板正、反向冲击力学性能及变形特征一致性较好,与单独托板相比,组合构件可实现吸能、延长冲击力整体作用时间、缩短震荡作用时间、改善托板承载特性等作用。研究成果为冲击地压巷道锚杆支护的托板及组合构件选取提供一定借鉴。
In rockburst roadway, the impact load will cause the interaction force between the components of bolt support system and surrounding rock to increase sharply, and the supporting plate is prone to deformation and failure under high force. In view of the above problems, the mechanical properties of three kinds of arched supporting plates and their combined components commonly used in coal mines were tested by using a microcomputer-controlled electro-hydraulic servo testing machine and a self-developed drop hammer impact testing device. The static load-displacement curve, impact time-history curve, displacement time-history curve and deformation and failure characteristics of the samples were obtained, and the impact resistance of anchor supporting plates and combined components was analyzed. The results show that under the static load, the bearing capacity of the supporting plate is 228-243 kN, and the maximum deformation is 14.10 mm. The deformation characteristics are as follows: the arch height is reduced, the four corners are tilted, and the connecting parts are transferred to the center of the circle. Under dynamic load, the deformation of the supporting plates all experienced three stages: arch height reduction, four corners lifting and flattening. When the impact energy was 500-3 000 J, the impact time-history curve showed a sharp rising stage, a shock stage and a rapid decline stage, while when the impact energy was 3 500-5 000 J, the impact time-history curve showed a sharp rising stage, a shock steady load stage, a shock rising stage and a rapid decline stage. With the increase of impact energy, the peak values of impact force of the samples are gradually increased. Compared with its static load, the peak value of dynamic load of the supporting plate sample is obviously larger than its static load. The displacement time-history curve of the samples can be divided into two stages: elastic-plastic deformation and springback deformation. In the elastic-plastic deformation stage, the deformation is linearly r
作者
吴拥政
周鹏赫
付玉凯
孙卓越
WU Yongzheng;ZHOU Penghe;FU Yukai;SUN Zhuoyue(Coal Mining and Designing Branch,China Coal Research Institute,Beijing 100013,China;CCTEG Coal Mining Research Institute,Beijing 100013,China;Coal Mining and Designing Department,Tiandi Science and Technology Co.,Ltd.,Beijing 100013,China;State Key Laboratory of Coal Mining and Clean Utilization,Beijing 100013,China)
出处
《煤炭科学技术》
CAS
CSCD
北大核心
2022年第11期1-11,共11页
Coal Science and Technology
基金
国家自然科学基金资助项目(51974160,52174080)。
关键词
冲击载荷
锚杆支护
落锤试验
拱形托板
组合构件
impact load
bolt support
drop hammer test
arched plate
combined components
