Study On Dynamic Bonding Performance Between Concrete And Reinforcing Bars

Under the influence of various adverse factors,the durability of reinforced concrete structures will inevitably decline during its service.Among them,the most adverse effect on the durability of concrete structures is steel corrosion.The research shows that the reason why the two can bear the load together is not only that they have similar temperature expansion coefficient,but also that the cohesive force is the basis of their joint work.And the corrosion of reinforcement will reduce the bonding performance between the two,thus causing irreparable damage to the reliability of reinforced concrete structures.Despite the current for bonding performance with the rules of corrosion rate in research has made many achievements,but most of them are focused on the bondslip,under static load and corroded reinforced concrete structure by dynamic loading such as earthquake,impact and explosion effect,thus explore under dynamic load of the corroded reinforced concrete bonding performance between the evolution law has important significance and practical value.In this paper three kinds of loading rate(0.1 mm/min,1 mm/min,10 mm/min)for four kinds of corrosion rate(0,1%,4%,8%)of concrete member center drawing experiment,analyzes the corroded reinforced concrete under different loading rate effect of bond properties change rule,studied in the loading rate and corrosion rate under the coupling effect of the bonding performance between concrete and steel change rule,mainly from the following several aspects:1.According to the central drawing experiment,the influence of corrosion rate and test loading rate on the ultimate bond strength between reinforced concrete is discussed,and the formula for calculating bond strength under the coupling effect of the two factors is obtained.2.The bond slip constitutive relation function of reinforced concrete is established under different corrosion rates and loading rates.3.Under different corrosion rates and loading rates,the distribution law of the bond stress of reinforced concrete structures along the anchorage length was obtained,and the bond slip constitutive relation of reinforced concrete along the anchorage length was further obtained.4.Based on the bond slip constitutive model in this paper,the model established by the nonlinear spring element is adopted through THE FINITE element software ABAQUS to simulate the bond failure process.The development law of bond properties under different corrosion rates and loading rates is analyzed and verified with the actual measurement results.