基于榆神矿区特厚坚硬煤层超大采高综放开采技术条件，针对散体颗粒模型在埋深较浅的坚硬煤层综放开采模拟中顶煤冒放情况与实际不相符的问题，对比黏结颗粒模型与无黏结散体颗粒模型力学性质，讨论两种模型适用条件，得出黏结颗粒模型更适合坚硬煤层综放开采模拟。阐述了黏结颗粒模型的建模和模拟过程:岩层内部采用平行黏结颗粒模型以模拟层内整体块体力学特性，层间采用光滑节理模型以模拟结构面力学性质;通过Fish语言和伺服控制原理实现液压支架初撑阶段、增阻阶段和恒阻阶段不同工况的模拟;根据支架顶梁位态采用逆向运动学方法更新支架整体位姿;通过Fish语言实现尾梁的不同幅度摆动。数值模拟结果表明:覆岩可形成下位基本顶不稳定砌体梁结构和上位基本顶稳定砌体梁结构，顶板来压步距介于10~20 m;顶煤破碎度和冒放性具有双周期性(走向周期与周期来压步距一致，表现为来压期间顶煤破碎较充分、冒放性好，优于非来压期间;垂向周期与顶煤层位相关，表现为下位顶煤破碎充分、冒放性好，优于上位顶煤);工作面煤壁整体稳定性较好，来压期间会出现煤壁破坏现象;液压支架总体处于较高的工作阻力状态;不同块度的顶煤冒放过程中可能形成小块度瞬时动态松散拱结构、中等块度不稳定拱结构和大块度稳定拱结构，尾梁成拱可采用“小拱小摆、大拱大摆”对策高效破拱，掩护梁成拱则需移架才可破拱。超大采高综放开采实践表明数值模拟结果与现场情况一致，黏结颗粒模型能较好地模拟埋深较浅的坚硬煤层综放开采顶煤冒放特征和矿压显现规律。本研究可为坚硬煤层顶煤冒放性和顶板覆岩结构数值模拟研究提供力学模型选择依据，为模拟过程实现方法提供借鉴。

Based on the mining conditions of longwall top-coal caving with super-large mining height and hard coal seam in Yushen mining area,this paper analyzed the difference between the actual situation of top coal caving and that of numerical simulation using unbonded particle model. By comparing the mechanical properties of bonded particle model and unbonded particle model,and investigating the applicable conditions of the two models,it was concluded that the bonded particle model is more suitable for the simulation of longwall top coal caving in the hard coal seam. This paper illustrated the process of modeling and simulation with bonded particle model. It was pointed out that the calibration of micro-parameters and macro-mechanical properties of particles should be carried out before modeling. The bonded particle model was used in the rock layer,while the smooth joint model was used to simulate the mechani- cal properties of the structural surface between layers. The simulation of various working conditions of hydraulic roof support,including setting load stage,resistance increasing stage and constant resistance stage,were realized through Fish language and servo control principle. Inverse kinematic was used to renew the pose of the whole hydraulic roof support according to the position of its canopy. Swing of different amplitude of rear canopy was realized through Fish language. The simulation investigation shows that the unstable voussoir beam was formed in the lower part of main roof and the stable voussoir beam was formed in the upper part of main roof,ant the roof weighting distance was about 10-20 m. The fragmentation and cavability of top coal presented double periodicity,which comprises strike periodicity and vertical periodicity. (The strike periodicity is corresponded with periodic caving span,and the top coal can be fully broken during the roof weighting period and the cavability is better than that of the non-weighting period. The vertical periodicity is related to the position of top coal,and the cavability of lower part of top coal is better than that of upper part. ) The overall stability of the coal face is relatively high,and the coal face spalling occurs during the weighting pe- riod,and the hydraulic roof support is in the state of high working resistance. The transient dynamic loose arch struc- ture,small unsteady arch structure and large stable arch structure can be formed during top coal caving with various fragmentation. The arch formed on the rear canopy can be broken by the method of “small arch small swing,large arch large swing” of the rear canopy,which is more efficient,while the arch formed on the caving shield can only be broken by the advance of the hydraulic roof support. Numerical results are consistent with the field test of longwall top coal ca- ving in Jinjitan coal mine,which indicates that the bonded particle model could be used to simulate the top coal caving and strata movement behavior of longwall top coal caving in extra-thick and hard coal seam. This research provides a reference for the numerical modeling of the top coal caving and the structure of overlying strata in hard coal seam with longwall top coal caving,which contributes to the selection of the mechanical model and the implementation of simula- tion process.