Wu Bowen, Wang Xiangyu, Bai Jianbiao, Wu Wenda, Meng Ningkang, Lin Huasheng
School of Mines, China University of Mining & Technology, Xuzhou 221116, People's Republic of China.
State Key Laboratory of Coal Resources and Safe Mining, Xuzhou 221116, People's Republic of China.
R Soc Open Sci. 2020 Oct 7;7(10):201105. doi: 10.1098/rsos.201105. eCollection 2020 Oct.
High pre-tension bolt is an effective strata control technique and is the key to ensure the stability of anchorage and roadway. Based on the performances of high energy storage tension rock bolts in different rock properties, this study proposed a constitutive model to describe the energy balance of anchor under uniaxial compression. UDEC was used to simulate the behaviour of anchor in coal under uniaxial compression and the results were analysed to study the rock mechanical properties, degree of damage and energy evolution. Simulation results showed that tension rock bolts can improve the mechanical properties and energy storage capacities of the anchor. The energy evolution was divided into three stages: (i) the external work was stored in the form of elastic strain energy ( ) in the anchor prior to the yielding strength; (ii) the elastic strain energy reached its maximum near the peak strength; (iii) energy was dissipated from fracture friction ( , plastic deformation ( ) and acoustic emission ( ) during post-peak stage. The installation of tension rock bolts was more suitable for medium hard rock (e.g. sandy mudstone), whereas it was not effective for hard rock (e.g. sandstone).
高预应力锚杆是一种有效的岩层控制技术，是确保锚固和巷道稳定性的关键。基于不同岩石性质下高储能张拉锚杆的性能，本研究提出了一个本构模型来描述锚杆在单轴压缩下的能量平衡。采用UDEC模拟锚杆在煤体单轴压缩下的行为，并对结果进行分析，以研究岩石力学性质、损伤程度和能量演化。模拟结果表明，张拉锚杆可以提高锚杆的力学性能和储能能力。能量演化分为三个阶段：（i）在屈服强度之前，外部功以弹性应变能（ ）的形式储存在锚杆中；（ii）弹性应变能在峰值强度附近达到最大值；（iii）在峰值后阶段，能量通过断裂摩擦（ ）、塑性变形（ ）和声发射（ ）耗散。张拉锚杆的安装更适合于中硬岩石（如砂质泥岩），而对硬岩（如砂岩）则无效。
