三点弯曲试验条件下加锚试样抗弯性能研究  

Study of Flexural Properties of Specimens with Anchors Under Three-Point Bending Test Conditions

作　　者：朱洪漠 臧传伟[1] 陈洋 许杰 樊春宇 ZHU Hongmo;ZANG Chuanwei;CHEN Yang;XU Jie;FAN Chunyu(College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590,China;Key Laboratory of Urban Security and Disaster Engineering,Ministry of Education,Beijing University of Technology,Beijing 100124,China;China Coal Xi'an Design Engineering Co.,Ltd.,Xi'an,Shaanxi 710054,China;Jinjitan Coal Mine of Shaanxi Future Energy and Chemical Co.,Ltd.,Yulin,Shaanxi 719000,China)

机构地区：[1]山东科技大学能源与矿业工程学院,山东青岛市266590 [2]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124 [3]中煤西安设计工程有限责任公司,陕西西安710054 [4]陕西未来能源化工有限公司金鸡滩煤矿,陕西榆林市719000

出　　处：《矿业研究与开发》2023年第3期124-128,共5页Mining Research and Development

基　　金：山东省自然科学基金项目(ZR2019MEE022)。

摘　　要：矿山开采过程中,锚杆布置对巷道顶板的支护至关重要。制作标准的岩石试件,使用变刚度煤岩动力试验破坏试验机对试件进行三点弯曲试验,对未加锚、加锚后顶板岩体的抗弯性能进行研究。试验结果表明:与未加锚试件相比,加锚后试样的峰值荷载显著增加,当锚杆间排距由20 mm×20 mm增加到40 mm×40 mm时,试样的峰值荷载先增加后减小,间排距为30 mm×30 mm时,试样取得最大值。试样弯曲破坏过程中上下表面分别产生压应变和拉应变,下表面的拉应变普遍大于上表面的压应变。无锚试样上下表面产生的应变值小于加锚试样,无锚试样在轴向荷载作用下更快发生脆性破坏。当锚杆间排距由20 mm×20 mm增加到30 mm×30 mm时,上下表面产生的应变量较接近,说明缩小锚杆间距一定程度上可以增加岩体的稳定性,但是当锚杆间距减小到一定数值时,对于试样整体稳定性的强化作用并不显著。During the mining process, the arrangement of bolt is crucial to the support of roadway roof. Standard rock specimens were made, and three-point bending tests were carried out on the specimens using the variable stiffness coal rock dynamic test failure tester, so as to study the flexural properties of the unanchored and anchored roof rocks. The results show that the peak load of the specimen increased significantly after the anchor was added, compared with the unanchored specimen. When the anchor bolt spacing increases from 20 mm×20 mm to 40 mm×40 mm, the peak load of the specimen increases first and then decreases. When the spacing is 30 mm×30 mm, the peak load of specimen gets the maximum value. Tensile and compressive strains are generated on the upper and lower surfaces of the specimen during bending damage process, and the tensile strain on the lower surface is generally greater than the compressive strain on the upper surface. The strain values generated on the upper and lower surfaces of the unanchored specimens were smaller than those of the anchored specimens, and brittle damage occurs more quickly in the unanchored specimens under axial load. When the anchor spacing is increased from 20 mm×20 mm to 30 mm×30 mm, the strain at the upper and lower surfaces is close, which indicates that reducing the anchor spacing can increase the stability of the rock mass to some extent, however, when the anchor spacing is reduced to a certain value, the strengthening effect on the overall stability of the specimen is not significant.

关 键 词：加锚试样 三点弯曲试验 抗弯性能 峰值荷载 

分 类 号：TD311[矿业工程—矿井建设] TU45[建筑科学—岩土工程]