Micro-analysis On The Cracking Of Hydraulic Concrete Structure Induced By Steel Bar Corrosion

As an important structure of water conservancy facilities,hydraulic reinforced concrete structures are exposed to the combined action of internal and external loads due to the long-term water-filled and complex working environment,and the frequent occurrence of rust expansion and cracking of their components has become an impact on the long-term safe service of hydraulic structures.An important cause of safety.In order to explore the mechanism of the protective layer cracking and falling off of the hydraulic structure caused by the expansion and cracking of steel bars,this article focuses on the problem of the cracking of hydraulic reinforced concrete structures induced by the corrosion of steel bars.From the perspective of macro and micro analysis,the cracking damage behavior of hydraulic reinforced concrete is analyzed.Carried out systematic analysis and research,and then developed the existing numerical simulation method for damage and cracking of hydraulic reinforced concrete structures.The main research results are as follows:(1)By analyzing the difference between hydraulic concrete and ordinary concrete,using MATLAB-ABAQUS joint modeling and simulation to simulate the mechanical behavior of hydraulic concrete under uniaxial tension from a meso scale,revealing that hydraulic concrete is in uniaxial tension.The failure law of tension;the stress-strain relationship of the simulation analysis is compared with the physical test and the standard calculation value.The result shows the accuracy of the digital simulation result and the validity of the method.(2)On the basis of the existing steel corrosion model,combined with the diffusion law of chloride ions in concrete and the bimodal phenomenon of the corner steel corrosion test,a corner steel corrosion model is proposed,and the corrosion distribution of the model is described by its displacement parameters.And it is compared with the distribution of the corrosion amount in the relevant steel corrosion test,which verifies the rationality and scientificity of the corrosion model built in the article.(3)Using the MATLAB-ABAQUS joint test platform,a systematic analysis was carried out on the development process of steel corrosion in hydraulic concrete cracks and the causes of structural corrosion expansion and cracking.The results confirmed the strength of hydraulic concrete,the diameter of the steel bars,the thickness of the protective layer,and the strength of the steel bars.Location is the main internal cause that affects the rust expansion and cracking of its components.(4)Using the established meso-level random aggregate model and considering the combined effect of multiple steel bars,the evolution process of corrosion and cracking of multiple steel bars in hydraulic concrete structures is analyzed by simulation,and the stress overlap effect caused by the corrosion of multiple steel bars is quantitatively analyzed.Another important factor in structural cracking.It was applied to a sluice project in Guangzhou,and the results showed that steel corrosion had hidden safety hazards to the safe operation of sluice projects.For this reason,the mathematical model method established in this paper can provide a method basis for project designers and operation and maintenance safety prediction.