预应力拼装桥墩工作机制及抗震性能研究

Evaluation of working mechanism and seismic performance of pre-stressed assembled piers

为探究地震作用下预应力拼装桥墩的工作机制,根据拼装桥墩荷载传递规律,结合集中塑性铰理论,推导给出预应力拼装桥墩荷载与变形的计算公式。采用有限元ANSYS建立并分析预应力拼装桥墩的力学特性和抗震性能,探讨预应力钢筋有效初应力、恒载轴向压力和普通钢筋配筋率参数对拼装桥墩抗侧移刚度及其承载力的影响规律。结果表明,预应力拼装桥墩应力分布与侧移荷载关系密切,预应力钢筋的有效初应力与桥墩抗侧移刚度和承载力呈正相关变化;恒载轴压力和普通钢筋配筋率对桥墩抗震性能影响不大,桥墩抗震耗能能力有限。

To explore the working mechanism of prestressed assembled piers under seismic action,the formulas for calculating the load and deformation of prestressed assembled piers are derived based on the load transfer law of assembled piers and the theory of concentrated plastic hinge.ANSYS was used to establish and analyze the mechanical properties and anti-seismic performance of prestressed assembled piers,the law of influence the initial effective stress,the axial load and the common steel reinforcement ratio on the lateral stiffness and the bearing capacity of the piers.The results show that the stress distribution of prestressed piers is closely related to the lateral load,and the effective initial stress of prestressed reinforcement is positively correlated with the lateral stiffness and bearing capacity of piers.The dead load axial pressure and the ratio of steel reinforcement have little effect on the seismic performance of piers,and the seismic energy dissipation capacity of bridge piers is limited.