Durability of concrete beams reinforced with CFRP sheet under wet-dry cycles and loading  

干湿交替与荷载作用下CFRP加固混凝土梁的耐久性(英文)

作　　者：李杉[1] 任慧韬[1] 黄承逵[1] 崔云飞[1] 

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,大连116024

出　　处：《Journal of Southeast University(English Edition)》2009年第3期376-380,共5页东南大学学报（英文版）

基　　金：The National Natural Science Foundation of China(No.50608013);Special Prophase Project on Basic Research of the National Department of Science and Technology(No.2004CCA04100)

摘　　要：The test results of eight concrete beams reinforced with carbon fiber reinforced polymer （CFRP） sheets subjected to an aggressive environment under a sustained load are presented. The beams are 1 700 mm long with a rectangular cross-section of 120- mm width and 200-mm depth. The beams are precracked with a four-point flexural load, bonded CFRP sheets, and placed into wet-dry saline water（ NaCl） either in an unstressed state or loaded to about 30% or 60% of the initial ultimate load. The individual and coupled effects of wet-dry saline water and sustained bending stresses on the long term behaviour of concrete beams reinforced with the CFRP are investigated. The test results show that the coupled action of wet-dry saline water and sustained bending stresses appears to significantly affect the load capacity and the failure mode of beam strengthened with CFRP, mainly due to the degradation of the bond between CFRP and concrete. However, the stiffness is not affected by the coupled action of wet-dry cycles and a sustained load.对8根持载与恶劣环境作用后的碳纤维增强聚合物(CFRP)加固混凝土梁进行了试验研究.梁的尺寸为1 700mm×120mm×200mm.首先采用4点分加载方式对梁进行预裂,卸载后粘贴CFRP片材,然后放入腐蚀环境.影响因素考虑了干湿交替与持载水平(持载水平分别为30%和60%混凝土梁极限荷载).分析了干湿交替单一因素和荷载与干湿交替双重因素对CFRP加固梁的长期性能.试验结果表明:荷载与干湿交替双重因素对CFRP加固梁的承载力和破坏形态影响较大,这主要是由于CFRP与混凝土界面的劣化引起;对CFRP加固梁的刚度几乎没有影响.

关 键 词：reinforced concrete beams REINFORCED carbon fiber reinforced polymers DURABILITY wet-dry cycles sustained load 

分 类 号：TU528.57[建筑科学—建筑技术科学]