网壳结构“折叠展开式”提升过程中动力响应分析

网壳结构折叠展开式提升过程涉及机构运动分析，动力效应十分明显．采用拉格朗日方程形式的多柔体动力学可以有效地避免刚度矩阵奇异以及刚度矩阵的分解、迭代复杂等问题．经过分析研究得出了在整个运动过程中各阶段的结构的动力特性，包括一些动力参数(初始加速度、提升高度、阻尼)对机构运动受力的影响以及机构在不同状态下的自振频率等．在跟踪了整体提升过程中的位移轨迹和各杆件单元的应力状态，并通过比较数值计算结果和实际测量数值后得出了可信的动力系数，为工程设计参数的选取以及网壳整体提升过程中的动力响应理论分析提供了有意义的参考．

Dynamic response analysis of deployable lifting construction process of reticulated shell structures

The dynamic lifting process of deployable reticulated shell structures was a mechanism motion process, which has noticeable dynamic effect. The motion equation of flexible multi-body system was presented in Lagrange formulation. Since the equations are uncoupled, no inversion of the stiffness matrix is required and no convergence checks are needed, which decreases the computation work greatly. The influence of dynamic parameters (initial acceleration, lifting height, damping, etc.) on the whole lifting motions was investigated as well as the natural frequency in different lifting conditions. Motion trajectory and the stress condition of all elements in lifting process were also investigated. According to the critical stress of the material, the dynamic coefficient of the structure was proposed. And the results are proved to be reliable according to the actual measurement values. The work here is very useful for the further analysis of the whole lifting process and the engineering construction design.