钢屋盖-钢筋混凝土支承结构连接系统的破坏机理及抗震性能研究

The large span hybrid structure is composed by the upper large span steel structure and the supporting reinforced concrete structure. The roof joint is a key point for connecting the upper steel roof structure and supporting reinforced concrete structure, and it is considered to be a weak point in the structure. Unfortunately, large numbers of large-span steel roof structures failed at the roof joints were observed in the past earthquakes. The failure of roof joint may cause the collapse of the roof structure and affect the occupation. In this proposed research, the theoretical, experimental and numerical study combined with earthquake reconnaissance are used to comprehensively investigate the failure mechanism of roof joint and effect of roof joint on the seismic behavior of large span hybrid structure under extremely severe earthquake. To enhance the resilience of the large span hybrid structure, a value-added roof joint using friction device is proposed. The research works include the following three parts: 1) Roof joint and value-added roof joints will be tested by pseudo-static loading, and the hysteretic behavior and failure mechanism will be recorded and analyzed. 2) Develop finite element models which can simulate the roof joints subjected to combination of actions and deformations. The analytical models will be calibrated by experiments in this project and previous studies, and then applied to system level. 3) Based on the improved simulation models, the seismic performance of the large span hybrid structure will be evaluated using the incremental dynamic analysis. The research results will contribute the seismic design and provide the technique background for the seismic performance of the large span hybrid structures, and enhance the seismic resilience of the large span hybrid structures. Moreover, it is expected to promote the researches on the performance-based seismic design for large span hybrid structure in China.

大跨钢屋盖混合结构是由上部钢屋盖下部钢筋混凝土支承结构组成，支座节点是连接上下部结构的重要构件。在以往的地震中观测到，支座节点是地震损伤集中的部位，它的破坏将直接影响到整体结构的安全性以及震后继续使用性。本项目采用理论分析、模型试验、数值模拟和震害观测等四种研究手段对支座节点在强震下的抗震性能和破坏机理，建立考虑支座节点行为的基于性能的抗震设计理论和方法；同时在支座节点处引入被动控制技术，提高整体结构的震后恢复能力。计划完成的主要内容包括：通过拟静力试验，研究支座节点在全过程受力机理和破坏机制；针对支座节点的受力特征，发展能够考虑多种受力条件及破坏特征的精细化数值计算模型；通过非线性动力增量分析方法，研究考虑支座行为的整体结构的抗震性能。研究成果将为大跨钢屋盖混合结构基于性能的抗震设计在我国的推广提供理论基础和技术积累，有助于提高我国大跨钢屋盖混合结构的抗震性能及震后恢复能力。

大跨钢屋盖混合结构是由上部钢屋盖下部钢筋混凝土支承结构组成，支座节点是连接上下部结构的重要构件。在以往的地震中观测到，支座节点是地震损伤集中的部位，它的破坏将直接影响到整体结构的安全性以及震后继续使用性。本项目采用了理论分析、模型试验、数值模拟和震害观测等四种研究手段对支座节点在强震下的抗震性能和破坏机理，建立考虑支座节点行为的基于性能的抗震设计理论和方法；同时在支座节点处引入被动控制技术，提高整体结构的震后恢复能力。完成的主要内容包括：通过拟静力试验，研究支座节点在全过程受力机理和破坏机制；针对支座节点的受力特征，发展能够考虑多种受力条件及破坏特征的精细化数值计算模型；过非线性动力增量分析方法，研究考虑支座行为的整体结构的抗震性能。研究结果表明，支座节点的抗震性能受加载高度、竖向轴力、钢底板开孔形式、混凝土边距的影响，并且指出开长孔钢底板能有效降低上部结构对支座的位移需求，完成新型支座的开发。在此基础上，通过整体结构分析标定构件层次与结构整体性能的对应关系，完善大跨钢屋盖混合结构的抗震性能综合评级方法及设计方法。本项目研究成果将为大跨钢屋盖混合结构基于性能的抗震设计在我国的推广提供理论基础和技术积累，有助于提高我国大跨钢屋盖混合结构的抗震性能及震后恢复能力。