持载与干湿循环作用下CFRP加固高强混凝土梁耐久性研究

发布时间：2018-04-13 02:38

本文选题：高强混凝土 + CFRP　；参考：《建筑结构》2017年21期

【摘要】：通过四点弯曲试验,研究并分析了在干湿循环和持续荷载共同作用下CFRP加固高强混凝土梁的耐久性。干湿循环介质采用3.5%的Na Cl溶液,循环次数设置0次、40次、80次和120次,持载等级为未加固钢筋混凝土梁极限荷载的0%,30%和60%。试验结果表明:干湿循环和持载作用后,加固梁的性能发生劣化,破坏方式逐渐由混凝土表层破坏向胶层与混凝土之间的粘结破坏发展;加固梁的极限荷载、跨中极限挠度、CFRP极限应变整体呈下降趋势,后期刚度显著降低,且随着持载等级提高,退化程度进一步加剧。
[Abstract]:The durability of high strength concrete beams strengthened by CFRP under the combined action of dry and wet cycles and continuous loads is studied and analyzed by four point bending tests.The dry and wet circulation medium is 3.5% NaCl solution, the cycle times are set 0 times, 40 times, 80 times and 120 times, the holding load grade is 0% 30% and 60% of the ultimate load of reinforced concrete beams without reinforcement.The test results show that the behavior of the strengthened beam is degraded after the dry and wet cycle and the holding load, and the failure mode is gradually changed from the surface failure of concrete to the bond failure between the rubber layer and the concrete, and the ultimate load of the strengthened beam,The ultimate strain of CFRP decreased and the stiffness of CFRP decreased significantly in the later stage, and the degradation degree was further aggravated with the increase of load holding grade.
【作者单位】：大连理工大学海岸和近海工程国家重点实验室;
【基金】：国家自然科学基金项目(51378089)
【分类号】：TU37

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