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为了提高RC墩柱的抗震性能,对分段钢纤维混凝土(Steel Fiber Concrete,SFC)预制壳壁抗震加固RC墩柱的设计方法及加固效能展开研究.首先研制开发了一种新型RC墩柱抗震加固措施—RC墩柱塑性铰区域外包分段SFC预制壳壁(预制壳壁内设置无黏结钢筋),通过理论推导与分析建立了该新型RC墩柱抗震加固措施的加固设计方法;然后选取实际钢筋混凝土桥梁中的RC墩柱为原型,通过加固前后RC墩柱模型的伪静力试验进行对比研究,依据试验获得的力-位移滞回曲线、骨架曲线对比分析承载力、延性以及耗能能力,校验这种新型RC墩柱抗震加固措施的有效性;并且依据分段SFC预制壳壁抗震加固RC墩柱伪静力试验数据确定的其力-位移骨架曲线,分析探讨该新型RC墩柱抗震加固措施设计方法的合理性.研究结果表明:分段SFC预制壳壁抗震加固措施能在不改变RC墩柱塑性铰位置的前提下,实现承载力、延性和耗能能力的明显提高;根据试验数据验证了所推导的加固墩柱的屈服弯矩及最大弯矩计算公式的有效性,从而在一定程度上例证了分段SFC预制壳壁抗震加固RC墩柱的承载力设计方法.研究结果可应用于分段SFC预制壳壁抗震加固RC墩柱的实际工程中,从而为提高RC桥梁的抗震性能提供可靠的技术支持.“,”In order to improve the seismic performance of RC pier columns,the design methods and effectiveness of RC pier columns seismically strengthened with precast steel fiber concrete (SFC) shell segments were investigated.Firstly,a new-type RC pier column seismic strengthening measure,that is,Precast SFC shell segment (with unbonded steel bars installed inside) wrapping the plastic hinge region of RC pier column,was developed.And its seismic strengthening design method was proposed by the theoretical deduction and analysis.Then,the RC pier column in the actual bridge composed of reinforced concrete was selected as a prototype.Based on the force-displacement hysteresis curve and skeleton curve resulted from the comparative experiments between the RC pier column model and the strengthened RC pier column model in the pseudo-static tests,the bearing capacity,the ductility and the energy dissipation capacity were compared and analyzed,and the validity of this RC pier column seismic strengthening measure was verified.Furthermore,based on the force-displacement skeleton curve resulted from the strengthened RC pier column models in the pseudo-static tests,the feasibility of the design method of RC pier column seismically strengthened with precast SFC shell segments was analyzed and discussed.The results show that the seismic strengthening measures of RC pier columns with precast SFC shell segments can obviously enhance the bearing capacity,ductility and energy dissipation capacity of RC pier column without changing their plastic hinge position.Meanwhile,according to the testing data,the feasibility of the formulas of yield moment and the maximum bending moment derived by RC pier column seismic strengthened with precast SFC shell segments,is verified.So the bearing capacity design method of RC pier column seismically strengthened by precast SFC shell segments is exemplified in some degree.The research will provide the reliable technical support for the practical engineering application of RC pier column seismically strengthened with precast SFC shell segments,so as to improve the seismic performance of RC bridge.