由于特厚松软煤层巷道顶煤层理裂隙发育严重、黏聚力小、强度低，为解决此类巷道围岩破碎变形不易控制及其支护结构失稳的技术难题，综合采用理论分析、相似材料模拟试验、数值模拟分析的研究方法，提出了特厚煤层巷道拱-梁耦合主动承载结构支护体系，阐述了组合梁、承载拱的形成与作用及拱-梁耦合作用机理；并以金地煤业回采巷道为研究对象，运用数值模拟详细研究了锚索关键参数（长度、预紧力、间排距）对拱-梁承载结构稳定性的影响；同时建立了拱-梁承载结构稳定性评价体系，以加权平均的计算方法对关键参数影响因次做出排序。研究结果表明：拱-梁耦合承载结构是巷道支护结构的主体，此结构的存在有效提高了特厚松软煤层巷道的围岩强度及稳定性，改善了围岩破碎变形，控制了巷道失稳；采用形态参数评价拱-梁承载结构稳定性具有一定的客观性，得到结构形态参数贡献系数分别为：拱体积0.3，拱心压应力0.3，弧长0.2，梁体积0.1，梁心压应力0.1；锚索关键参数对拱-梁承载结构稳定性的贡献率依次为：间排距贡献率365.21%，预紧力贡献率80.34%，长度贡献率30.98%，影响作用为间排距>预紧力>长度；针对金地煤业回采巷道，优化支护参数（锚索间排距1 m×1.6 m、预紧力150 kN、锚索长度8 m、锚杆间排距0.8 m×0.8 m）后的拱-梁承载结构可保持巷道稳定，满足生产要求。

Due to the serious development of cleavage and fracture, low cohesion and low strength in the top coal of the extra thick and soft coal seam roadway, in order to solve the technical problemsof difficult control of crushing and deformation of surrounding rock of such roadway and the instability of supporting structure, theoretical analysis and similar material simulation tests and numerical simulation analysis were adopted comprehensively, an arch-beam coupling active bearing structure support system for extra-thick coal roof roadways was proposed, The formation and function of composite beams and load-bearing arches and the mechanism of arch-beam coupling were elaborated. The mining roadway of Jindi Coal Industry was used as the object, the influence of key parameters of anchor cable (length, pre-tightening force and row spacing) on the stability of arch-beam bearing structure was studied in detail by numerical simulation. At the same time, the stability evaluation system of the arch-beam bearing structure was established, and the influence factors of key parameters were calculated by weighted average method. The results show that the arch-beam coupling bearing structure is the main part of the roadway supporting structure, which effectively improves the strength and stability of the surrounding rock in extra-thick soft seam roadway, improves the crushing deformation of surrounding rock and prevents the instability of roadway. Applying morphological parameters to evaluate the stability of the arch-beam bearing structure has certain degree of objectivity, and the contribution coefficients of structural morpho logical parameters are as follows: arch volume 0.3, arch core compressive stress 0.3, arc length 0.2, beam volume 0.1 and beam core  compressive stress 0.1. The contribution rates of key parameters of anchor cables to the stability of arch-beam bearing structure are as follows: the row spacing contributes 365.21%, the pre-tightening force contributes 80.34%, and the length contributes 30.98%. That is, the effect of the inter-row distance > the effect of the pre-tightening force > the effect of the length. For the mining roadway in Jindi Coal Industry, the support parameters are optimized (the row spacing between anchor cables is 1 m×1.6 m, the pre-tightening force is 150 kN, the length is 8 m and the row spacing between anchors is 0.8 m×0.8 m), which can maintain the stability of the roadway and meet the production requirements.  

0 引言

1 工程背景

   1.1 工程概况

   1.2 围岩原位特性

2 拱-梁结构主动承载机理

   2.1 组合梁的形成与作用

   2.2 承载拱的形成与作用

   2.3 拱-梁耦合作用机理

3 拱-梁承载结构相似模拟验证

   3.1 试验模型建立

   3.2 试验方案与加载

   3.3 拱-梁结构承载特性

4 拱-梁承载结构稳定性数值分析与优化

   4.1 拱-梁承载结构数值模拟

   4.2 拱-梁承载结构参数优化

5 拱-梁承载结构关键参数影响因次

6 工程应用

7 结论