Improvement And Discussion Of Rectangular Hoop Confined Concrete Model

The study of nonlinear structural behavior is always a main topic in structural research, and computer simulation is a main method of studying structural behavior. Computer simulation of structure, material model used in the computer simulation analysis is an important aspect of influencing the accuracy and reasonableness of simulation results.The current proposed number of confined concrete model have the two main differences: Curve shapes and Feature points of curve. Differences of model will certainly affect the bearing capacity and ductility of structural elements. Most comparative research on the model still remain in the material level and component simulation model to compare different analysis, There is no single Model of to consider several characteristic changes in the composition of component simulation. Feature points on the parameters of model was put forward mainly through experiments and simple mechanical derivation. Not through a series of finite element analysis parameters of feature points on the model analysis.In order to deeply study the effect of disparity model on the bearing capacity and ductility of the specimen as well as the effect of hoop reinforcement on the bearing capacity of concrete, the following tasks in this paper should be accomplished:①This article will discuss the confined concrete stress - strain curve and the curve shape changes in different characteristic points on the bearing capacity, ductility level simulation results; thus choose the simple and practical feature points satisfied the engineering precision curve equation and the equation. The results show that: the changes of Model of confined concrete peak stress and peak strain, the bearing capacity and ductility have significant impact; Ultimate strain of the model changes (reflected in the slope of the model) to almost no effect on the bearing capacity of elements, ductility greater impact. component of Low reinforcement rate and axial compression ratio, the model changes the relative changes caused by the high bearing capacity reinforcement of low ductility of the axial compression ratio components greater.②By analyze the confined concrete finite element and qualitative theory of hoped concrete mechanism, find out the elements influencing confined concrete behavior. The results can be seen from the analysis: effects confined concrete model the main differences: concrete strength ,volume tie ratio , hoop reinforcement and spacing. ③Propose a comprehensive effect coefficient that can affect confined concrete,To gather the needed test data, figure out the relationship between feature points and synthesis parameters by regression method; propose the Confined concrete stress - strain model.④Make a comparison between the proposed confined concrete model and existing model with regard to test data. Calculated by the proposed model the peak strength and strain relative to other model has further improved to make the stress - strain curves and the experiment can achieve better agreement.