【作者】 董旭华；

【导师】 肖岩； 郭玉荣；

【作者基本信息】 湖南大学 ， 结构工程， 2006， 硕士

【摘要】 从已建桥梁在历次地震中破坏的共同特点可以看出:现代混凝土桥梁结构中,因钢筋混凝土桥墩破坏导致桥梁严重破坏甚至倒塌,已成为桥梁震害的主要特点,特别是桥梁短柱的破坏尤为严重,而脆性剪切破坏是钢筋混凝土短柱最为危险的破坏方式之一。因此研究桥梁短柱的抗震性能以及抗震加固性能对于减少桥梁破坏和损失具有重要的意义。而纤维增强塑料(FRP)的复合材料加固方法由于其具有轻质高强、易于现场施工和良好的耐腐蚀性等优良性能,在工程界逐渐得到广泛应用。本文针对抗震地区的桥梁短柱进行了抗震性能和滞回性能的试验研究,具体进行了以下几个方面的工作:(1)设计制作了3个剪跨比为1.5高度直径比为3.0的大比例圆形截面试件,其中一个作为既有短柱不进行加固,另外两个进行GFRP加固;(2)分析了GFRP约束作用对桥梁短柱的破坏特征、承载力、刚度、能量耗散能力、延性等方面的影响,从受力角度分析了GFRP加固桥梁短柱的受力性能及机理;(3)在数值分析的基础上,全面考察了轴压比、FRP体积配置率、混凝土强度、纵向钢筋屈服强度和配筋率及长细比等因素对FRP加固柱滞回关系的影响,给出了FRP加固钢筋混凝土柱的弯矩-曲率和荷载-位移关系的恢复力模型,基于恢复力模型的弯矩-曲率和荷载-位移关系计算结果与试验结果吻合较好,可为结构的弹塑性动力分析提供参考;(4)对全文进行了总结,指出了本文的创新点及值得进一步研究的问题。更多还原

【Abstract】 Failure or even collapse of bridge structures in past earthquakes were largely. In particular, shear failure of short bridge pier columns is the most dangerous failure pattern due to the brittle nature. Consequently,it is quite meaningful to study the seismic resistance performance and retrofitting for reducing bridge damages and losses. As FRP composite material has a series of advantages such as lightweight, high strength, easy construction and good resistance to corrosion and fatigue, the retrofitting method utilizing FRP is widely used in civil engineering. This thesis presents a test program on seismic behavior of short bridge columns.(1) A total of three reinforced concrete large scale circular short columns were designed, whose shear-span ratios are 1.5. One column was tested under“as-built”condition and the others were retrofitted with GFRP.(2) The failure mode, strength, stiffness, energy capacity and ductility of the columns with glass fiber reinforced polymer were described in details to investigate the seismic behavior and mechanism of columns under cyclic load.(3) On the basis of experimental and theoretical analyses, parameters including axial compression ratio, steel strength, ratio of reinforcement, concrete strength and slenderness ratio that affect hysteretic behavior are studied. Simplified models for the moment-curvature response and load-restoring force are suggested. Results from the suggested models show good agreement with the experimental results, and the models can be applied to elastoplastic dynamic analysis of structure.(4) In the end, this thesis summarizes the novel ideas and raises some problems for future studies.更多还原