CFRP组合加固改善高强混凝土方柱抗剪性能试验研究

利用低周反复荷载试验手段,研究了4种不同CFRP(carbon fiber reinforced polymer)布加固方式(横向包裹CFRP布、横向包裹CFRP布和植螺栓杆组合,以及横向包裹CFRP布和宽、窄夹板组合)对高强混凝土柱抗剪性能的作用.通过分析以上4种不同加固方式对试件的延性、塑性铰转动能力,以及刚度退化等方面的影响,得到如下结论:4种加固方式均可改善抗剪不足高强混凝土方柱的抗剪性能,有效提高试件的变形能力,其中横向包裹CFRP布和窄夹板组合加固方式加固效果最好;同时,在试验基础上提出适用于高强钢筋混凝土柱的刚度退化模型,并与试验结果进行比较,发现试验结果与模型吻合较好.

Experimental investigation on shear behavior of high strength concrete square columns retrofitted with CFRP hybrid methods

In order to investigate the effects of these four retrofitting CFRP hybrid methods (wrapped CFRP sheets method, embedded bolt bar combining with wrapped CFRP sheets hybrid method and wide or narrow clamping plates with wrapped CFRP sheets hybrid method) on the shear behavior of high strength concrete square columns, low reversed cyclic loading test is used to systematically analyze the ductility, rotation capacity of the plastic hinge and stiffness degradation. The experimental results show that all the retrofitting methods mentioned above can effectively improve the shear behavior and deformation of specimens. Meanwhile, the narrow clamping plates with wrapped CFRP sheets hybrid method is the best one among the four methods. In addition, a subsection model of stiffness degradation is proposed, and the calculated results are also in good agreement with experimental data.