Influence of Steel and Carbon Fiber Reinforcement Bars on Seismic Performance of Precast Segmental Bridge Columns

为了得到快速施工和利用新材料的预制节段桥墩设计方法，研究了部分钢筋替换为碳纤维筋时预制节段桥墩的水平承载力和破坏等级．首先通过与拟静力试验结果的比较证明了仿真分析的正确性，然后研究了部分普通钢筋替换为碳纤维筋，对拟静力循环荷载和地震地面运动分别作用时预制节段桥墩响应的影响．结果表明：碳纤维筋能提高桥墩水平承载力，增大有效刚度，降低等效粘滞阻尼比和滞回能量耗散．地震时程计算表明：部分普通钢筋替换为碳纤维筋时，使得预制节段桥墩在较强烈地震底面运动下不倒塌．利用绝对能量法分析了桥墩在地震地面运动下的能量吸收和耗散情况，并主要研究了4种桥墩试件在3种不同地震地面运动作用下的输入能量和滞回能量耗散，结果是随着桥墩输入地震能量的增大滞回能量耗散增长缓慢．

A new design method aiming at improving construction efficiency and incorporating new materials is proposed, in which the effect of substituting partial ED bars with carbon fiber bars in precast segmental bridge piers on the lateral strength and damage level is investigated. The simulation is first taken to validate the proposed method by comparing with the pseudo static test results. Then study is focused on the effect of substituting partial ED bars with carbon fibre reinforced bars on the response of piers under the loading of pseudo static cyclic load and seismic ground motion. The results show that adding carbon fiber reinforcement bars can enhance the lateral strength of column, and increase the effective stiffness, as well as decrease the equivalent viscous damping ratio and hysteretic energy dissipation. It is found that carbon fibre reinforcement bars help keep the column survival under the ground motion with high intensity. The discussion is made on the column response under ground motion using an absolute energy method. The input energy and hysteretic energy absorbed in the four specimens under the three ground motion are also analyzed, which leads to the conclusion that, the increase of input energy is inversely proportional to the increase of the hysteretic energy of columns.