直接基于位移的预制拼装墩柱抗震设计

基于性能的设计是桥梁抗震设计未来的发展方向之一，而基于位移的抗震设计方法是实现基于性能设计的最佳途径。预制拼装预应力混凝土桥墩的受力特性与普通钢筋混凝土现场浇筑桥墩的受力特性有较大区别，为了实现中高烈度区桥梁快速化施工建造，对基于位移的预制拼装预应力混凝土桥墩抗震设计方法进行研究。基于节点弯矩-曲率分析和非弹性位移反应谱，提出基于位移的预制拼装桥墩设计方法。首先根据基于性能的设计思想，结合预制拼装桥墩的受力特点，确定5个性能水平和对应的工程需求参数；然后推导塑性转动从接缝张开算起的目标位移的计算方法；提出单柱式预制拼装桥墩直接基于位移的抗震设计步骤，对该种旗帜形滞回响应结构的等效黏滞阻尼、非弹性位移反应谱、设计水平力、弹性开裂刚度等内容进行研究。以某拟静力往复加载试验预制拼装桥墩为例进行直接基于位移的设计，并进行纤维模型非线性地震时程分析，比较两者结果，验证所提方法的正确性。

Seismic Resistant Design of Precast Segmental Columns Using Direct Displacement Based Design Method

Performance based design is one of the promising directions of future bridge seismic design. Further, the displacement-based design method is the optimum solution to realize performance based design. The loading performance of precast segmental pre-stressed concrete bridge columns (PSPCs) differs from that of cast-in-place steel reinforced concrete bridge columns. To construct bridges rapidly in moderate-to-high seismic intensity zones, the implementation of the displacement-based design method of PSPCs was investigated. The direct displacement-based design (DDBD) method of PSPCs was proposed upon joint moment-curvature analysis and inelastic displacement response spectra. Firstly, five performance levels and the corresponding engineering demand parameters were determined according to performance-based design philosophy referring the loading features of PSPCs. Subsequently, the calculation method of target displacement was deduced where plastic rotation was calculated from joint opening. The direct displacement-based seismic resistant design procedures of single PSPC was proposed. In the procedure, the calculation method and the influencing factors of equivalent viscous damping, inelastic displacement response spectra, design lateral force, and elastic cracked stiffness of this kind of flag shaped hysteresis response structures, were studied. The PSPCs of a quasi-static cyclic loading test were selected as example to show the implementation of DDBD. The earthquake nonlinear time history analyses were conducted using a fiber model. The time history analysis results were compared, validating the proposed DDBD method.