摘要:
为提高深部软岩巷道锚杆支护承载能力，有效控制巷道围岩变形，采用锚杆拉拔正交试验对锚固承载特性影响因素进行研究，分析不同影响因素作用效果，并以试验结果为依据针对性提出高预应力全长锚固支护技术，研发了预应力全长锚固锚杆，通过理论计算对预应力全长锚固围岩承载能力加以分析，并以潘三煤矿17102(3)工作面回风巷道为工程背景，采用数值模拟和现场试验方式与传统加长锚固支护、全长锚固支护进行对比验证。研究表明：锚杆拉拔失效首先发生在锚固体与试块黏结界面，锚杆拉拔锚固失效经历了弹性—塑性—破坏的动态阶段，不同锚固因素产生锚固效果不同，在拉拔失效发展过程中的体现也有所区别。其中试块强度和锚杆预应力对锚杆极限拉拔力影响程度显著，并且极限拉拔力的大小与试件强度和预应力值呈正相关。根据试验结果提出高预应力全长锚固锚杆支护技术，研发的预应力全长锚固锚杆采用全长锚固提高岩体强度的同时分段施加预应力，与传统加长锚固支护、全长锚固支护相对比，高预应力全长锚固支护技术实现了锚杆在全长锚固的基础上使得预应力向围岩内传递，从而增大围岩压应力区范围，形成更有效的锚固围岩承载结构。工程实践表明，预应力全长锚固支护技术可有效控制深部破碎软岩巷道围岩大变形，实现深部巷道围岩的稳定性控制。
Abstract:
In order to improve the bearing capacity of bolt support in the deep soft rock roadways and effectively control the deformation of the surrounding rock of the roadway, the bolt pull-out orthogonal test was used to study the influencing factors of the anchor bearing characteristics and analyzed the effects of different influencing factors. Based on the test results, the high-prestress full-length anchoring support technology was proposed, and then the prestressed full-length anchor bolt was developed, and the analysis was carried out based on Pansan Coal Mine 17102 (3). The return air roadway of the working face was used as the engineering background, and the numerical simulation and field test methods were used to compare and verify the traditional lengthened anchor support and full-length anchor support. The research shows that the pull-out failure of the anchor rod first occurs at the bonding interface between the anchor and the test block, and the pull-out anchor failure of the bolt has undergone a dynamic stage of elasticity-plasticity-destruction. Different anchoring factors produce different anchoring effects, and their manifestations are also different. Among them, the strength of the test block and the prestress of the bolt have a significant influence on the ultimate pull-out force of the bolt, and the magnitude of the ultimate pullout force is positively correlated with the strength and prestress of the test specimen. According to the test results, the high-prestressed full-length anchor bolt support technology is proposed. The developed pre-stressed full-length anchor bolt adopts full-length anchoring to improve the strength of the rock mass while applying pre-stress in sections. Compared with the traditional lengthening anchor support and full-length anchor support, the high prestressed full-length anchor support technology realizes the transfer of prestress to the surrounding rock on the basis of full-length anchorage of the bolt, thereby increasing the range of the surrounding rock compressive stress zone and forming a more effective anchoring bearing structure of surrounding rock. Engineering practice shows that the pre-stressed full-length anchoring support technology can effectively control the large deformation of the surrounding rock in the deep broken soft rock roadway, and realize the stability control of the surrounding rock in the deep roadway.
百度学术
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