Study On Macroscopic Constitutive Relations Of Reinforced Concrete Under Axis-tension Test

This paper relies tutor Professor Zhou Zhixiang assumed 973 planned project " the Theory of Behavioral Evolution and Safety Monitoring Method of Bridge Structure " and the project of the Chongqing Natural Science Foundation "Bridges face sensing method and Safety Evaluation System", explored a simple and accurate test method for reinforced concrete specimen under uniaxial tension, study on the uniform constitutive relation of the nominal stress and the macroscopic strain. The main work and conclusions are as follows:① A new idea is proposed in allusion to the complexity of modeling the whole-process analysis of reinforced concrete bridge and the large calculation quantity. This idea can both include the interaction between the steel bars and concrete and cover the unified constitutive relationship of cracks occurring and development situation. The relationship between nominal stress and macroscopic strain of the reinforced concrete is built;② Base on the basic knowledge of elastoplastic theory of reinforced concrete under axis-tension,12 groups experimental studies on reinforced concrete short column with different reinforcement ratio and different concrete strength are conducted. We can get the test method of reinforces concrete tensile stress-strain curve. Under the condition of axial tension, the mechanical behavior, form of crack propagation, failure pattern and macroscopic stress-strain curve during the whole process are obtained;③ Test results show that our test method is simple, easy to produce specimens, tensile stress uniformity during the eccentricity is well controlled, experimental data dispersion is small, reinforced concrete uniaxial tensile test is a viable method;④ By analyzing the observed macroscopic stress-strain curve and using the Matlab numerical analysis software to simulate, the stress-strain curve equation of the whole process of reinforced concrete under axis-tension is obtained;...