液压支架装备通常用于采煤工作面的支护。液压支架在工作过程中承受了大量冲击载荷，导致其动态稳定性受到威胁。为研究四柱支撑掩护式支架在对称与非对称承载工况下顶梁及掩护梁承受冲击载荷时的动力学响应特征，采用动力学软件Adams以等效变刚度阻尼系统代替立柱的方法，建立了支撑掩护式支架的数值分析模型。其中，顶板压力由主动静载荷垂直施加于顶梁上方，冲击载荷垂直于顶梁及掩护梁向下施加。基于上述模型，分析了不同冲击载荷作用于支架顶梁与掩护梁时支架关键部位的动力学响应，以及偏置加载对支架稳定性的影响。随后通过设置不同立柱初撑力，讨论了液压支架在非对称支撑条件下承受冲击载荷时的动力学特性。结果表明，单一顶梁冲击载荷条件下，前立柱载荷变化系数达到1.41，对顶梁前端冲击载荷最敏感。顶梁和掩护梁同时承受冲击载荷时，支架各铰接点对于顶梁前端与掩护梁上部区域作用的冲击载荷响应更剧烈，最大载荷变化系数为0.64，极大地影响液压支架整体稳定性。支架承受横向扭矩时，偏置载荷作用于不同位置对支架承载性能的弱化效果基本一致，且偏置载荷的大小与削弱效果呈正相关。在考虑立柱不同初载比时，顶梁-掩护梁铰接点对初载比变化的敏感程度最高，且前立柱初撑力不足时将对支架承载性能形成最大削弱效应。研究结果可辅助优化支撑掩护式支架结构，改善液压支架承载可靠性。

The hydraulic support equipment is usually used to support the roof in underground mining. During this process, the support bears frequent impact load, which greatly weakens its dynamic stability. To study the dynamic response characteristics of the support,  when it bears the impact load at the top beam and shield beam, the numerical model of the support is established using ADAMS and the equivalent variable stiffness damping system was used to replace the column system. An active static load is applied vertically above the top beam to simulate the roof gravity force, and the impact load is applied downward perpendicular to the top beam and shield beam. Based on the above model, the dynamic response of the key parts of the support, when different impact loads are applied to the top beam and shield beam, and the influence of offset loading on the stability of the support are analyzed. Then, when considering asymmetric bracing conditions, the dynamic characteristics of hydraulic support under impact load are discussed by setting different initial support forces. The results show that when under a single impact load, the load variation coefficient of the front column reaches 1.41, which is the most sensitive to the impact load at the front end of the top beam. When the top beam and shield beam bear the impact load at the same time, the support hinge joint response more violently to the impact load acting on the top beam end and the upper area of the shield beam, and the maximum load change coefficient is 0.64, which greatly affects the overall stability of the hydraulic support. When the support bears to lateral torque, the weakening effect of offset load acting on different positions on the bearing performance of the support is the same, and the magnitude of offset load is positively correlated with the weakening effect. When considering the different initial load ratios (ILR) of the column, it is found that the hinge joint of top beam and shield beam is the most sensitive to the change of ILR, and the insufficient initial support of the front column has the greatest weakening effect on the bearing performance of the support. The research results can help to optimize the structure of the support shield support and improve the bearing reliability of the hydraulic support.

0 引言
1 支撑掩护式液压支架数值模型建立
1.1 支撑掩护式液压支架刚柔耦合模型
1.2 立柱系统刚度分析
1.3 静态加载测试
2 冲击载荷加载方式
3 冲击载荷作用下液压支架动态响应
3.1 顶梁-掩护梁铰接点力响应
3.2 掩护梁-前连杆铰接点力响应
3.3 掩护梁-后连杆铰接点力响应
3.4 立柱力响应分析
3.5 偏置载荷作用于顶梁的力学响应分析
4 非对称载荷工况对支架稳定性的影响
4.1 非对称载荷工况下立柱特性曲线分析
4.2 非对称工况下液压支架承载性能分析
5 结论