Experimental Study On Interfacial Bond Fatigue Performance Of CFRP-Concrete Under Marine Environment

Nowadays, Carbon Fiber Reinforced Polymer(CFRP) is widely recognized and adapted in area of reinforcement of civil engineering, which has drastic advantage of high specific strength and stiffness, good corrosion resistance, anti- fatigue performance and convenient construction. A lot of researches and realistic engineer suggest, CFRP reinforcement structure can deliver effective stress by adhesive property of CFRP and concrete interfacial. CFRP after reinforced may be under cyclic loading for a long time and also marine environment as RC structures such as highways in the coastal area and railways bridges and ports. Fatigue loading and environmental factors may lead a certain damage degree to reinforcement effect, therefore, this dissertation simulates marine environment by chloride, sulfate salt and complex solution, which studies fatigue performance of CFRP-concrete interface by adopting double- lab shear test. The content are as follows:(1)Researches on interface bond behavior of three kinds of CFRP-concrete under static force loading activity after corrosion. The result shows, corrosion activity of saline solution may decrease bonding limited bearing capacity of interface and interfacial fracture energy, which can also decrease end slippage and increase stress-strain improvement speed. Stripping damage interface improves from concrete surface to adhesive layer, moreover, longer the corrosion time, more apparent the phenomenon. What is more, the corrosion activity of complex solution leads the most virtual influence to bonding performance of interface.(2)Influence that stress level towards bonding fatigue performance of CFRP-concrete interface. The result shows, stripping length of interface, shear force area and end slippage will increase respectively with increasing fatigue load. Meanwhile, there is no apparent difference of bearing capacity when remained transport length is over effective bond length; higher stress level, more falling range of remained bonding capacity of interface.(3)Study on fatigue performance of CFRP-concrete interface under marine environment. The result shows, stripping damage interface of species after corrosion will improve to adhesive layer with the increasing of corrosion age under fatigue load and also improve with increasing stress level. Besides, increasement of stress level and corrosion age will also accelerate stress-strain delivering speed and slope of curve of end slip. Meanwhile, fatigue life of species is shorter under environmental factors which shows more discreteness.