松软煤层锚固孔底扩孔锚固机理及锚固性能研究

Study on anchoring mechanism and anchoring performances of bottom reaming for anchoring borehole in soft seam

针对松软煤层巷道锚杆锚固力低,制约松软煤层巷道锚杆支护技术发展的问题,采用锚固孔孔底倒楔形扩孔锚固提高锚杆的锚固性能,利用自行研发的锚固孔孔底单翼扩孔装置进行力学分析、实验室试验、相似模拟和井下现场试验,试验结果表明:松软煤层锚固孔孔底倒楔形锚固,可以使锚杆的锚固性能显著提高,尤其是锚杆达到最大锚固力后的残余锚固力提高近1倍,为松软煤层巷道锚杆支护的广泛应用提供了技术支持。

According to the problem that a low anchoring force of the bolt applied to the soft seam gateway,which restricted the bolt support technology development of the soft seam gateway,the anchor hole anchoring after inverted wedge reaming at the bottom of the borehole was provided to improve the anchoring performances of the bolt. The mechanics analysis,lab experiment,similar simulation and underground site experiment were conducted with the self- developed bottom single wing device of the anchoring borehole. The experiment results showed that the reversed wedge anchoring of the bottom in the anchoring borehole of soft seam could obviously improve the anchoring performances of the bolt. Especially the residual anchoring force of the bolt was increased by nearly one time after the bolt reached the max anchoring force,and could provide the technical support to wide application of the bolt support applied to the soft seam gateway.