深部工程软岩巷道“连续双壳”治理底鼓机理研究

In China, the mines of deep mining are increasing year by year. As a result of high-stress, surrounding rock of deep roadway is characterized by engineering soft-rock and serious deformation and destruction. Large floor heaving is a distinct characteristic of strata behaviors in deep engineering soft-rock roadway (especially its depth>800m) and its controlling is very difficult. Therefore, controlling floor heaving is the key of surrounding rock controlled in deep roadway. A new technique is applied onsite that is “continuous double shell” controlling floor heaving of “bottom shallow hole grouting (shallow shell body) + deep-anchor-beam with high-pressure grouting (deep shell body) ” and its effect is very good, but its mechanism and related parameters is still vague understanding, and should be to study deeply and systematically.. According to the engineering practice and the previous research result, a new theory of the “continuous double shell” controlling floor heaving has be proposed. Aiming at the difficult problem of controlling floor heaving in deep engineering soft-rock roadway, through mechanical analysis, numerical and laboratory similar simulation and on-site verification, mechanism of the “continuous double shell” controlling floor heaving is revealed, mechanical model of “continuous double shell” controlling floor heaving is established, shell mechanic parameters of “continuous double shell” is optimized, theoretical and technological system of “continuous double shell” controlling floor heaving is built, which may enrich the theory of deep roadway support and provide guidance for engineering practice of controlling floor heaving in deep roadway.

我国深部开采的矿井逐年增多，深部巷道围岩由于高地应力作用，表现为工程软岩特性，变形破坏严重，其中底鼓量大是深部工程软岩巷道（特别是埋深>800m）矿压显现的显著特点，治理非常困难，因此，底鼓治理是深部巷道围岩控制的关键。课题组现场应用了“底板浅孔注浆（浅部壳体）和深部锚索束+高压注浆（深部壳体）”的“连续双壳”治理底鼓技术，治理效果良好，但对其机理和相关参数的认识仍然模糊，尚需深入和系统地研究。. 根据工程实践和前期研究成果，提出了深部工程软岩巷道“连续双壳”治理底鼓理论。针对深部工程软岩巷道底鼓治理难题，通过力学理论分析、数值模拟、实验室相似模拟和现场验证研究手段，揭示深部工程软岩巷道“连续双壳”治理底鼓机理，建立“连续双壳”治理底鼓力学模型，优化“连续双壳”壳体参数，构建“连续双壳”治理底鼓理论体系和技术体系，丰富深部巷道支护理论，指导深部巷道底鼓治理工程实践。

针对深部巷道强烈底鼓难控制问题，以及课题组现场成功实施底板浅孔注浆（浅部壳体）和深部锚索束+高压注浆（深部壳体）”的“连续双壳”治理底鼓技术但机理尚不明晰的双重问题，在项目研究期内，课题组开展了深部巷道底鼓类型、底鼓机理、底鼓控制原理及配套关键技术等系列研究，力争在深部巷道底鼓治理理论与技术方面有所突破。.对矿井巷道底鼓现状进行了全面的调研与分析，将深部巷道底鼓划分为5种类型；构建了深部巷道围岩力学模型，解析了深部巷道围岩形变规律，揭示深部巷道蠕变流动型底鼓形成机理，提出了深部巷道薄厚组合连续双壳支护结构控制底鼓方法，揭示了薄壳与厚壳协同控制底鼓机理；建立了挤压流动型底鼓力学模型，阐明了巷道底鼓力学机制，提出了巷道主动抗滑抑制底鼓方法及底鼓控制原理。实验研究了岩石在反复工程扰动下的损伤破裂规律和水作用下的崩解性破坏特征，揭示了高应力场、地下水、反复工程扰动共同作用诱发岩石损伤破裂机制。利用数值模拟、相似材料模拟等方法，分析了不同应力场环境下巷道薄厚组合壳结构参数和底板抗滑桩力学参数对底鼓控制的效果影响，为现场工业性试验提供了基础。研发出了深部巷道波纹钢（薄壳）-锚注体（厚壳）连续双壳加固关键技术、复杂构造区巷道围岩双壳加固关键技术、深部巷道分时段构筑壳结构的连续双壳加固关键技术、动压扰动下深部巷道底板钢管混凝土桩底鼓治理关键技术等系列巷道底鼓控制技术。成果在现场进行了工业性试验，已在河北、山西、内蒙古等矿区进行了推广应用。研究成果具有理论和指导工程实践双重价值，丰富了深部巷道底鼓控制理论，促进了深部巷道支护技术的发展。