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通过三个不同条件的工作面实测，揭示了浅埋煤层采场矿区显现基本规律，指出顶板台阶下沉是由单一关键层顶板破断失稳造成的，顶板存在结构效应。通过相似模拟实验和分步开挖数值模拟分析，得出顶板破断机理为拉破坏，老顶初次破断具有非对称性，老顶周期性破断后可形成不稳定铰接结构。采用岩块实验、模拟实验和数值分析，系统地研究了老顶岩块铰接点的挤压和摩擦性质，确定了顶板结构定量化分析的关键参数──岩块端角挤压系数和摩擦系数。在实验研究和实测分析基础上，首次将初次来压分为两个阶段，分别建立了老顶触矸前的“非对称三铰拱”结构和触矸后的“单斜岩块”结构模型。提出了浅埋煤层采场老顶周期来压的“短砌体梁”结构和“台阶岩梁”结构模型。通过顶板结构稳定性分析，揭示了顶板的强烈来压和台阶下沉是由结构滑落失稳造成的，确定了控制顶板滑落失稳所需的支护力，奠定了采场顶板控制的理论基础。在顶板结构分析的基础上，指出浅埋煤层采场支架处于“给定失稳载荷”状态，在顶板载荷确定中引入了载荷传递因子，按支架与围岩共同承载的观点给出了采场支护阻力的确定方法和计算公式。分析了采场支护阻力的影响因素，指出了顶板控制的经济有效途径。通过实测分析和初步实践，验证了研究结?
The results show that the roof subsidence is caused by the failure of a single key roof, and the roof has structural effect. Through analog simulation and step-by-step excavation numerical simulation, it is concluded that the roof breaking mechanism is pull failure, the initial breaking of the roof is asymmetric, and the unstable roof structure can be formed by the periodic breaking of the roof. Based on the rock block experiment, simulation experiment and numerical analysis, the extrusion and friction properties of the hinge point of the old roof block are studied systematically, and the key parameters of the roof structure quantitative analysis are determined-the rock corner compression coefficient and the friction coefficient . On the basis of experimental research and field measurement, the first time the pressure is divided into two stages, the “asymmetrical three-hinged arch” structure before the gangue pre-gangue and the “monocline rock” structural model . The “short masonry beam” structure and the “step rock beam” structure model of the shallow top coal seam stope are proposed. Through the stability analysis of the roof structure, it is revealed that the strong pressure of the roof and the sinking of the steps are caused by the sliding-down of the structure, and the supporting force needed to control the sliding-down of the roof is determined, laying the theoretical foundation for the roof control of the stope . Based on the analysis of roof structure, it is pointed out that the stope of shallow seam is in a state of “given buckling load”, and the load transfer factor is introduced in the determination of roof load. The stope Determination of supporting resistance and calculation formula. The influencing factors of stope support resistance are analyzed, and the economical and effective way of roof control is pointed out. Through the experimental analysis and preliminary practice, we verify the research conclusion?