预应力CFRP加固损伤钢筋混凝土墩柱的抗震性能试验研究

Experimental Study on Seismic Performance of Damaged Reinforced Concrete Piers Strengthened with Prestressed CFRP

为了研究预应力CFRP加固初始损伤程度不同钢筋混凝土墩柱的抗震性能,设计并制作了4个钢筋混凝土墩柱试件,其中3个为带有不同预损伤的试件,1个为对比试件。对各损伤墩柱塑性铰区采用施加相同预应力的CFRP加固并进行低周反复荷载试验,获取各试件破坏过程和破坏特征。基于实测水平力-荷载滞回曲线、骨架曲线探讨了预应力CFRP加固对不同损伤程度钢筋混凝土墩柱的滞回性能、位移延性、耗能等重要抗震性能指标的影响。结果表明:使用预应力CFRP加固不同损伤程度的墩柱试件,损伤柱的承载能力、延性性能、滞回耗能等抗震性能均在一定范围内有所提高,提高程度随初始损伤的增大而减小;预应力CFRP加固损伤程度为轻度到中度的钢筋混凝土墩柱可以提高其安全储备。

In order to study the seismic performance of reinforced concrete piers with different initial damage degree strengthened by prestressed CFRP(carbon fiber reinforced polymer),four reinforced concrete pier specimens were designed and fabricated,including three specimens with different pre-damage and one comparative specimen.The plastic hinge area of each damaged pier was strengthened with CFRP with the same prestress,and the low cycle repeated load test was carried out to obtain the failure process and failure characteristics of each specimen.Based on the measured horizontal force load hysteretic curve and skeleton curve,the influence of prestressed CFRP reinforcement on the hysteretic performance,displacement ductility,energy dissipation and other important seismic performance indexes of reinforced concrete piers with different damage degrees was discussed.The results show that the bearing capacity,ductility,hysteretic energy dissipation and other seismic performance of damaged pier columns strengthened with prestressed CFRP are improved in a certain range,and the degree of improvement decreases with the increase of initial damage.Prestressed CFRP can improve the safety reserve of reinforced concrete piers with mild to moderate damage.