基于损伤控制的内置连续柱-柱端滑移摩擦节点钢框架结构抗震性能研究

Because of unpredictable location and degree of damage in conventional steel frame structures based on the design principle of strong-column-weak-beam, loss optimization damage control has attracted considerable interests for seismic application. Without the restriction of the strong-column-weak-beam mechanism, this project proposes an innovative scheme to control damage of steel frame structures at the system level, integrating new seismic techniques, such as continuous column concept, energy dissipation mechanism of column end hinges and friction-slip energy dissipation connections, into this theme to achieve a goal of controlling the global failure mode, the energy dissipation mechanism and its effect. A series of research works will be conducted by theoretical analyses, experimental tests and numerical simulations, starting from connection, substructure to entire structure. The project will provide rational construction guidelines and establish theoretical hysteretic models of frame column end joint and continuous column end joint, and investigate the mechanical behavior of the friction-slip connection and its effect on the dynamic stability of frame column. Besides, a quantitative relation of structural seismic performance illustrated by inter-story drift will be developed to depict the reaction mechanism of Built-in continuous column improving inter-story drift distribution as well as verifying seismic performance of the system and its resilience after earthquake. Finally, purposes of the project are to improve the seismic performance and resilience of steel frame structures, reduce the post-earthquake loss and supplement the modern seismic design theory of steel structures, which would demonstrate the beneficial influence of the proposed system on both science and society.

由于基于传统延性“强柱弱梁”机制设计的钢框架结构在强震中损伤位置和损伤程度不可控、且震害损失严重，因此基于“损失最小的损伤控制”抗震设计在抗震领域引起广泛关注。本项目摆脱“强柱弱梁”机制禁锢，融合连续柱概念、柱铰耗能机制、摩擦滑移耗能节点等抗震新技术，从系统层次上提出钢框架结构损伤控制创新方案，实现整体失效模式可控、耗能机制可控和耗能效果可控的目标。应用理论分析、物理试验和数值模拟等方法，开展从节点、构件、子结构到整体结构系统研究，构建框架柱端和连续柱端节点的合理构造和理论滞回模型，揭示柱端摩擦滑移节点力学特性及其对框架柱动力稳定性的影响规律，建立基于层间位移角的结构抗震性能量化关系，探索内置连续柱改善结构层间位移角分布的作用机理，验证体系抗震性能及震后可恢复性。项目成果对提高钢框架结构抗震性能和震后恢复能力，减少震后损失，完善现代钢结构抗震设计理论，具有重要科学意义和社会意义。

避免建筑物在地震作用下发生倒塌或出现严重损伤是当前抗震设计和实践的核心科学问题。项目基于系统能力设计法和地震作用能量平衡原理，以结构整体倒塌模式可控、构件损伤可控为目标，创新构建了多种钢框架结构地震损伤控制体系，应用理论分析、物理试验和数值模拟等方法，开展从节点、构件、子结构到框架的多维度研究。取得了四个方面的主要成果：.（1）构思了弧面端承式、L形连接件式、摩擦耗能摇摆式等三种低损伤柱端节点型式，着眼于节点的工作机制和运行性能，结合静力性能及拟静力性能研究，对三种节点的构造细节进行了全面探索，归纳了合适的构造措施，提出了节点的理论力学模型。.（2）得到了H型钢框架柱地震荷载作用下的局部失稳形态和轴向缩短规律；进行柱脚以及柱两端设置低损伤滑移摩擦节点钢框架柱的抗震稳定性研究，验证了低损伤滑移摩擦节点的工作性能、及其对框架柱抗震稳定性的改善效果。.（3）构建常规框架、柱脚滑移摩擦节点框架、柱端滑移摩擦节点框架以及曲线隅撑和滑移摩擦节点框架等四种框架子结构，获得损伤状态、滞回性能曲线等参数，建立层间位移角的结构抗震性能量化关系；研究表明柱端设置滑移摩擦节点，能实现框架主构件不损伤且保持稳定的承载力；在此基础上加设曲线隅撑，可有效提高框架的承载力和刚度，且能在地震作用时实现损伤时序。.（4）建立了不同层高的纯钢框架结构和内、外置连续柱钢框架结构模型，考虑构件强度与刚度退化本构关系，对比分析了内、外置连续柱对钢框架结构抗震倒塌机制的影响，得到了钢框架抗地震倒塌连续柱刚度需求参数；将滑移摩擦节点布置于内置连续柱钢框架结构的柱脚及柱端，提升了内置连续柱钢框架结构的抗震性能。.研究成果为构建低损伤钢框架结构提供了多种节点样式和系统构成，为分层装配式钢结构、既有钢结构改造提供了理论和试验支持，对韧性钢结构的发展具有重要的理论意义。.项目实施期间，公开发表论文14篇，申请或授权专利5项，培养研究生20名。