带耗能构件双柱式桥墩抗震机理及设计方法研究

Earthquake resilient structures have emerged as one of the frontiers of earthquake engineering field, including structures with energy dissipation components. However, studies on double-column pier with energy dissipation components are in the stage of development and it lacks systematic theoretical and experimental investigations. Therefore, theoretical analyses, numerical simulation and shake table testing are carried out to investigate the seismic mechanism, the damage mechanism and the seismic design method of the double-column pier with energy dissipation components. The studies are as follow: theoretical models on the seismic performance of the double-column piers with energy dissipation components are deduced to determine the contribution of the seismic performance of the energy dissipation components to these of the double-column pier, such as stiffness, strength and energy dissipation; the reasonable performance parameters and the yield displacements tolerance between the energy dissipation components and columns are investigated to achieve the earthquake resilient function, the controllable yielding sequence and the transformational energy dissipation mode of the double-column pier with energy dissipation components, and to clarify the energy dissipation mechanism of the energy dissipation components to the double-column pier; nonlinear dynamic characteristics of the double-column piers with energy dissipation components are investigated to discuss its isolation performance; several advantages and disadvantages of several finite element models of the double-column piers with energy dissipation components are discussed, then a simplified simulation method is established for practical projects; the practical design method is presented for the seismic design of the double-column piers on the earthquake resilient function. The research results could be useful for the earthquake resilient function, the seismic design and the seismic design codes of double-column piers.

可恢复功能结构已成为地震工程领域的研究前沿，带耗能构件结构是其主要型式之一，但带耗能构件双柱式桥墩的研究处于起步阶段，缺乏系统的理论和设计方法研究。本项目通过理论分析、数值模拟和振动台试验，对带耗能构件双柱式桥墩的抗震机理、损伤机制以及设计方法进行研究，主要包括：理论推导带耗能构件双柱式桥墩抗震性能分析模型，确定耗能构件对双柱式桥墩性能的影响程度；研究耗能构件与墩柱性能参数的配置关系及其屈服变形容差，实现带耗能构件双柱式桥墩的功能可恢复、屈服时序可控和耗能模式演化等特征，揭示耗能构件对双柱式桥墩的抗震机理；研究带耗能构件双柱式桥墩的非线性动力特征，探讨其隔震性能机理；研究带耗能构件双柱式桥墩几种抗震分析方法的优缺点和适用性，建立简化模拟方法；最终，构建带耗能构件双柱式桥墩的抗震设计方法，供工程设计应用。研究成果将为双柱式桥墩的功能可恢复、抗震设计和有关规范指南的制定提供理论依据和分析方法。

可恢复功能结构已成为地震工程领域的研究前沿，带耗能构件结构是其主要型式之一，但带耗能构件双柱式桥墩的研究处于起步阶段，缺乏系统的理论和设计方法研究。因此，深入开展地震作用下带耗能构件双柱式桥墩的抗震机理、设计理论以及分析方法等基础性研究工作，无疑具有重要的理论意义与工程应用前景。本项目通过理论分析推导，建立了带耗能构件的双柱式桥墩抗震性能分析的理论计算模型，确定耗能构件对双柱式桥墩抗震性能的影响程度。通过数值模拟和试验研究，比较研究带耗能构件的双柱式桥墩的纤维有限元模型和集中塑性铰模型等有限元模型，建立了其抗震性能分析的简化模拟方法，采用集中塑性铰和纤维单元分析方法预测的抗震性能与试验结果吻合较好，且两种分析方法能合理反映桥墩最大荷载后的强度下降、刚度退化和耗能水平下降等现象。基于数值方法和试验技术，研究了耗能构件对双柱式桥墩的性能贡献、耗能机理以及对双柱式桥墩性能可恢复功能的效果，验证了耗能构件可有效改善双柱式桥墩抗震性能，减小墩柱曲率和降低了墩柱的地震损伤。在理论模型、数值模拟和试验研究的基础上，设计了带耗能构件的双柱式桥墩的抗震设计流程，建立了带耗能构件的双柱式桥墩的抗震设计方法。本研究成果将为双柱式桥墩的抗震设计、维修加固以及有关规范指南的制定提供理论依据和分析手段。