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为研究无粘结预应力筋连接的干接缝节段拼装桥墩在水平向低周往复位移荷载作用下的抗震性能和不同接缝形状的影响,建立了平面接触型和干接承插型两种接缝形式的实体有限元模型。其中混凝土采用损伤塑性模型,普通钢筋和预应力筋采用双折线模型,接缝处采用库仑摩擦模型。进行非线性时程分析,发现桥墩主要依靠接缝交替张开闭合提供水平变形能力,墩柱的破坏主要由底层节段混凝土压坏引起。通过两模型滞回特性、骨架曲线、延性性能和残余变形的对比,发现采用干接承插型接缝的桥墩与采用平面接触接缝的桥墩相比,最大承载力与耗能能力相当,但强度稳定段长,延性较好,残余位移也较小,具有更好的抗震性能。
In order to study the seismic performance and different joint shapes of dry piers assembled with unbonded prestressed tendons under horizontal reciprocating displacement, A kind of solid finite element model in seam form. Among them, the damage plastic model is adopted for concrete, the double rebound model is adopted for ordinary steel bars and prestressed tendons, and the Coulomb friction model is used for joints. Nonlinear time-history analysis shows that the piers mainly rely on the joints alternately open and close to provide the horizontal deformation capacity. The pier damage is mainly caused by the crushing of the bottom segment concrete. By comparing the hysteretic characteristics, the skeleton curves, the ductility properties and the residual deformations of the two models, it is found that the maximum bearing capacity and energy dissipation capacity of the piers with dry joints are comparable to those of the piers with the flat contact joints Stable length of strength, good ductility, residual displacement is also smaller, with better seismic performance.