强震下结构的损伤演化行为是结构失效的主要原因，本项目以大跨空间网格结构为研究对象，研究此类结构在强震下的损伤多尺度效应及其失效机理。从结构的多尺度物理机制及耦合机理出发，研究适用于结构损伤非线性分析的多尺度建模理论和高效的计算方法。考虑结构材料尺度的损伤演化行为，建立复杂受力状态下的材料动力损伤本构模型和结构的地震损伤模型，探索损伤累积效应由低阶尺度向高阶尺度迁移转化的规律。提出强震下杆件失效及整体结构破坏的判别准则，基于结构的多尺度精细化分析模型，模拟结构的地震损伤破坏过程，探讨杆件损伤、局部失效和整体结构破坏之间的内在联系，揭示结构的强震破坏机理。在此基础上深入研究结构地震失效模式优化及地震损伤破坏过程控制的理论和方法，提出提高结构强震下抗倒塌能力的控制措施。本研究对揭示大跨空间网格结构的地震损伤演化规律和倒塌破坏机理，增强此类结构的抗震能力具有重要的理论意义和应用价值。

The evolution of the structural damage under earthquake is an important reason of the failure of the structure. In this project the multi-scale effect of damage and failure mechanism are researched for the Long-Span Space Lattice Structures. Firstly, the multi-scale physical mechanism and its coupling mechanism under earthquake of this kind structure are studied to build the multi-scale analysis model，and an effective calculation method is also put forward for the nonlinear analysis of the structural damage. Secondly, the dynamic damage constitutive relations of the structural material and the structural seismic damage model under complicated loading states are set up through the analysis the evolution behavior of the structural damage on the material scale, and then the transformation law of the damage cumulative effect between different scales is explored. Thirdly, a multi-scale refinement analysis model is taken to simulate the seismic failure process of the structure and the failure criterions are put forward for the structural members and the structure. The links of the member damage, local failure and the collapse of the whole structure are investigated to reveal the seismic failure mechanism of the structure. Lastly, a theory and method are studied for the optimization of the failure mode of the structure to the control of the damage process, and measures are presented to improve the earthquake collapse resistance. This study is to reveal the failure mechanism and the evolution rule of the earthquake damage of the Long-Span Space Lattice Structures. It has important theoretical significance and application value for the improvement of the seismic resistance of this kind of structure.