| After the year 2000, China’s transportation construction developed quickly with each passing day. But in recent years, with the traffic volume and overload phenomenon increasing rapidly due to the economic development, many roads and bridges have exceeded the bearing capacity which designed many years ago so greatly that makes them suffered damages in varying degrees, and these roads and bridges are still in used. Bonded steel-plate reinforced method is used in various bridges widely as an important strengthening method, and the epoxy glue as an adhesive which the method uses, makes the concrete and steel-plate works together well under the loads. But the interfacial stress distribution of the epoxy glue is very complex, and whenever the value of interfacial stress is greater than the adhesive- capacity value of the epoxy glue, the bonded steel-plate reinforced structure will be destroyed with steel-plate separates brittlely. Therefore, this paper has studied on the characteristics of the bonded steel-plate reinforced concrete beams in detail by establishing separate ABAQUS finite element simulation model, obtained typical interfacial stress distribution curves, and drawn the conclusion that the glue-concrete interface is weaker than the glue-steel-plate interface. At the time, this paper also has put forward the reasonable thickness of the steel-plate, thickness of the epoxy glue, and the better cross-section of the steel-plate to reduce the interfacial stress concentration at the edge of the steel-plate and ensure the concrete beams and steel-plate working together, by analyzing the influencing factor like the value of the load, the way of loading, thickness of the steel-plate, thickness of the epoxy glue, shape of the steel-plate’s cross-section, and separation of the steel-plate.At the same time, people also concerns about the remaining life of the structure after strengthening by bonded steel-plate reinforced method. But at present, there is few the nondestructive evaluation data for the structure after strengthening by bonded steel-plate reinforced method, and there is scarcely a way to predicate the residual life of the strengthened structure. In the bonded steel-plate reinforced method, the epoxy glue plays a vital "nexus" role for the effect of interfacial adhesion, and no matter the normal life of reinforced concrete or the normal life of the steel-plate is greater than the epoxy glue. Therefore, the author starting with the epoxy glue, has designed the aging test for bonded steel-plate reinforced structure. According to the test results, the author has fitted out the mechanical property aging-curve of the epoxy glue, and the Arrhenius-curve of the epoxy glue. In the end, the author has used the Arrhenius-curve to predicate the residual life of the structure after strengthening by bonded steel-plate reinforced method for Chongqing Municipality. |
PDF Full Text Request