氯盐干湿循环次数对TRC加固RC柱抗震性能影响  

Influence of chloride dry-wet cycles on seismic behavior of RC columns strengthened with TRC

作　　者：李耀[1,2] 尹世平[1,2] 刘鸣[2] 杨扬[2] LI Yao;YIN Shiping;LIU Ming;YANG Yang(State Key Laboratory for Geomechanics & Deep Underground Engineering,China University ofMining and Technology,Xuzhou 221116,China;Jiangsu Key Laboratory of Environmental Impact and Structural Safety in Engineering,China University ofMining and Technology,Xuzhou 221116,China)

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116 [2]中国矿业大学江苏省土木工程环境灾变与结构可靠性重点实验室,江苏徐州221116

出　　处：《建筑结构学报》2019年第4期94-103,共10页Journal of Building Structures

基　　金：国家自然科学基金项目(51478458)

摘　　要：为了研究在侵蚀环境下纤维编织网增强混凝土(textile reinforced concrete,TRC)加固RC柱的抗震性能,设计制作了9根钢筋混凝土方柱,其中,3根为对比柱,其余6根为TRC加固柱。采用时控开关控制的水泵定时抽水的方式对水槽内的全部试件进行氯盐干湿循环试验。氯盐干湿循环完成后,对9根试件进行了低周往复加载试验,分析了不同氯盐干湿循环次数对TRC加固柱抗震性能的影响。结果表明:在氯盐干湿循环下,TRC加固能够限制裂缝的发展,提高试件的开裂荷载、屈服荷载和峰值荷载,增大加固试件屈服前的刚度,延缓屈服后的刚度退化,提高加固试件的变形能力和耗能能力;氯盐干湿循环会降低TRC的力学性能;氯盐干湿循环对加固试件的开裂荷载影响不大,但随着氯盐干湿循环次数的增加,加固试件的屈服荷载和峰值荷载减小,耗能能力降低,位移延性系数先增大后减小再增大,在试件屈服前后,刚度退化速率变化规律与位移延性系数相同,但到了位移加载后期,氯盐干湿循环次数对试件刚度退化无明显影响。因此,随着氯盐干湿循环次数的增加,TRC加固RC柱的整体抗震性能有一定程度降低。To investigate the seismic behavior of RC columns strengthened with textile reinforced concrete(TRC)in a chloride corrosive condition,a total of nine reinforced concrete(RC)columns were prepared.Three columns were used as the controls,and the others were strengthened with TRC.All of the columns were then tested under chloride dry-wet cycles with pumping controlled by a time control switch.After that,low-frequency cyclic loading tests were conducted on all columns,and the effect caused by chloride dry-wet cycles on the seismic behavior of columns was discussed.The experimental results show that TRC in corrosive conditions can restrict the development of concrete cracks,and increase the cracking load,yield load and peak load of the strengthened columns;it can also increase the stiffness of strengthened columns before yielding and delay the stiffness degradation after yielding.Therefore,TRC can improve the deformation and energy dissipation capacity of strengthened columns.The mechanical properties of TRC decrease in a chloride corrosive condition.The chloride dry-wet cycles have little influence on the cracking load of strengthened columns based on the test results in the present study.However,with the increase of dry-wet cycles,the yield load,peak load and energy dissipation capacity of strengthened columns are reduced.In addition,the displacement ductility coefficient first increases,then decreases and increases again.The change of stiffness degradation rate is similar to the displacement ductility coefficient until the yielding of columns.At the later stage of loading,the dry-wet cycles have little effect on the stiffness degradation.Therefore,with the increase of the chloride dry-wet cycles,the seismic behavior of RC columns strengthened with TRC degrades to a certain extent.

关 键 词：纤维编织网增强混凝土(TRC) 钢筋混凝土柱 氯盐干湿循环次数 低周往复加载试验 抗震性能 

分 类 号：TU375.303[建筑科学—结构工程]