Study On Bearing Capacity Of Reinforced Concrete Beam Under Multi-factor Coupling

The durability of reinforced concrete bridges has decreased in the process of actual use by the external environment factors such as carbon dioxide,chloride ion erosion.The results of erosion are that the structure is damaged and the bearing capacity drops.So it is a crucial problem on the structure durability how to analyze qualitatively the attenuation of the bearing capacity.This paper is based on the basic research project(2013,319,812,100)of the ministry of communications about the structural damage and the attenuation of bearing capacity of concrete bridges.The bearing capacity of the reinforced concrete beam has been studied under the multi-factor coupling by the artificial environment.The paper analyzes the attenuation law of bending bearing capacity and shear capacity of reinforced concrete beams in the corrosion environment.The degradation models have been established according to the results of the experiment.The mainly work is as follows:The erosion of the reinforced concrete beams is simulated by multiple factors such as carbon dioxide,chloride ion erosion in the artificial environment.The results show that tensile stress has a promoting effect and compressive stress has an inhibitory effect on carbonation and chloride ion corrosion of concrete.This paper analyzes the attenuation law of bending bearing capacity and shear capacity on the performance degradation of reinforced concrete beams.The finite element models on bending bearing capacity and shear capacity of the reinforced concrete beams are established and the results are comprared with the experiment results.The results of the experiment show that the bending bearing capacity and shear capacity decreases and the stiffness decreases gradually with the increase of corrosion and there is a linear relationship between the bearing capacity and the corrosion rate of steel bars.The degradation models of bending bearing capacity and shear capacity have been established according to the results of the experiment.