冲击地压矿井巷道吸能防冲液压支架防冲效果研究

Research on energy absorption characteristics and anti-bump effect of anti-bump hydraulic support in rockburst mine roadway

为提升现有巷道支护体系的抗冲击能力,在已有常规巷道门式液压支架的基础上进行吸能防冲设计,并从能量吸收、液压支架整体变形以及冲击荷载作用下支护反力大小、波动性等方面进行研究分析,验证吸能液压支架在冲击荷载作用下的支护性能。首先基于能量守恒原理对支护吸能特性的理论依据及必要性进行研究分析,结合现有预折纹自引导吸能装置进行数值模拟与试验分析。数值模拟结果与试验过程一致,明确了数值模拟的可行性,并总结其变形吸能特性,进而对常规液压支架进行吸能防冲设计。采用数值模拟的方法从多方面进行常规液压支架与吸能液压支架的防冲性能对比,结果表明:相同冲击荷载作用下,液压支架施设吸能装置后的吸能液压支架的支架部分塑性能仅为常规支架的65%,最大等效塑性应变仅为常规液压支架部分的62%,屈服区域面积占比为常规液压支架的85%,反力均值为常规液压支架的53%;采用快速傅里叶变换对支护反力进行频谱分析,从而对比分析常规液压支架与吸能液压支架在冲击荷载作用下支护反力的波动性,吸能液压支架的支护反力较常规液压支架更为平稳。结合各方面结果分析,吸能液压支架具有良好的承载特性及吸能防冲能力,施设吸能装置对于液压支架本身以及巷道围岩土体均具有一定的保护作用。

In order to improve the impact resistance of the existing roadway support system, an energy-absorbing and anti-scouring design was carried out on the basis of the existing conventional roadway portal hydraulic support, and the support reaction force was obtained from the energy absorption, the overall deformation of the hydraulic support and the impact load. The size, fluctuation and other aspects were studied and analyzed to verify the supporting performance of the energy-absorbing hydraulic support under impact load. Firstly, based on the principle of energy conservation, the theoretical basis and necessity of supporting energy absorption characteristics were studied and analyzed, and the numerical simulation and experimental analysis were carried out in combination with the existing pre-folded self-guided energy absorption device. The numerical simulation results were consistent with the test process, so that the feasibility of numerical simulation is clarified, and its deformation and energy absorption characteristics were summarized, and then the conventional hydraulic support was designed for energy absorption and impact prevention. Then, the numerical simulation method was used to compare the anti-bump performance of conventional hydraulic supports and energy-absorbing hydraulic supports from various aspects. The results show that under the same impact load, the plastic performance of the energy-absorbing hydraulic support bracket after the energy-absorbing device is installed is less than 65% of that of the conventional support, and the maximum equivalent plastic strain is only less than 62% of the conventional hydraulic support. The yielding area is less than 85% of the conventional hydraulic support, and the average reaction force is less than 53% of the conventional hydraulic support;the fast Fourier transform is used to perform frequency spectrum analysis on the support reaction force, so as to compare and analyze the fluctuation of the support reaction force of the conventional hydraulic support and the energy-absorbing hydraulic support under the impact load. The supporting reaction force of energy-absorbing hydraulic supports is more stable than conventional hydraulic supports. Combined with the analysis of various results, the energy-absorbing hydraulic support has good load-bearing characteristics and energy-absorbing and anti-bump capabilities. The facility energy-absorbing device has a certain protective effect on the hydraulic support itself and the surrounding rock and soil of the roadway.