预应力碳纤维条带加固高轴压比混凝土圆柱抗震性能试验研究

为了研究预应力碳纤维条带加固高轴压比混凝土圆柱的抗震性能，进行了7个钢筋混凝土圆柱试件的低周反复荷载试验，其中1个为设计轴压比0.82的未加固对比柱试件，另外6个为不同高轴压比下的预应力碳纤维条带加固柱试件，主要考虑了环向预应力和轴压比两种参数对加固柱抗震性能的影响。研究结果表明：采用预应力碳纤维条带加固高轴压比混凝土圆柱后，其承载力、延性性能、耗能能力均有大幅度提升；预应力纤维条带提供的环向主动约束力能够有效抑制斜向剪切裂缝的开展，加固后高轴压比圆柱呈现出弯曲破坏特征；采用试验数据回归分析方法，得到了预应力碳纤维条带加固混凝土圆柱极限荷载点位移 Δm计算式，计算结果与试验结果吻合较好。

Experimental study on seismic behavior of circular RC columns strengthened with pre-stressed CFRP belts under high axial compression

To study seismic behavior of circular RC columns strengthened with pre-stressed CFRP belts under high axial compression, seven circular RC columns including one contrast column under 0.82 axial load ratio and six columns strengthened with pre-stressed CFRP belts were tested with the main experimental parameters being the prestressing level of CFRP belts and axial load ratio. Test results show that the strength, ductility and energy dissipating capacity of the columns with high axial load ratio are improved significantly after being strengthened with pre-stressed CFRP belts. The diagonal shear cracks of columns can be effectively confining with the active lateral confining stress provided by pre-stressed CFRP belts, and the failure mechanism of the columns with high axial load ratio may show more feature of flexure with satisfactory ductility. Using statistic regression analysis, the formula of displacement Δm of the peak loading point is proposed and the result of the model shows good agreement with the test result.