Numerical Analysis Of Cracking Behavior Of SMA Composite Concrete

The SMA reinforced concrete beam structure of the shape memory alloy is a new structure developed after the reinforced concrete structure.It is mainly divided into two types:SMA in concrete beams and concrete beams.Using SMA to expose the joints at both ends of the concrete beam and energizing them,the SMA will undergo phase change,and the material properties will change very differently.The performance of the concrete beam will be improved and the deflection under load of the concrete beam will be reduced.Even some cracks in the concrete body have a delay and repair effect.For example,bridges,stations,underground buildings,high-rise buildings,etc.However,researchers at home and abroad at the present stage,although research on shape-memory alloy reinforced concrete beams has certain results,there is still a certain distance from the widespread use of SMA.In this paper,the finite element method is used to perform nonlinear numerical analysis of the shape-memory alloy reinforced concrete beam,and the constitutive relation,cracking and failure of the concrete material are analyzed.Cracked concrete beams were simulated from various factors such as the concrete model,crack size and location,SMA diameter,and temperature to form a comprehensive SMA repair concrete crack law.The analysis results show that:(1)The concrete model is the most influential crack repairing effect.This result has a certain reference effect on the selection of concrete for special occasions;(2)The weakest is the diameter of SMA itself,which will hardly cause crack repair.The difference in effect.(3)SMA shows a consistent linear change for different crack size repairs.The system's comprehensive simulation analysis of the crack repair effect and the SMA repair concrete crack law.With reference to concrete structure design specifications of the concrete beam size and structure,a simulation analysis was performed.It has achieved almost identical results in theory,simulation,and experimental values.It is verified that the SMA has improved the rigidity of the cracked concrete standard beam under the energization excitation.The preliminary study of this paper can illustrate the feasibility of applying the shape memory alloy to high-rise buildings or long-span bridges.By appropriately controlling its temperature or pre-strain,the prestress value of the structure or component can be increased as needed,or It is used to compensate for structural prestress loss,adjust the dynamic characteristics of the structure,and improve unfavorable stress conditions.At the same time,the current situation of SMA-reinforced concrete at home and abroad has been excavated and absorbed.The performance of concrete beams and SMA has been known and understood in detail,and a detailed analysis of the application of ANSYS to simulate such nonlinear concrete has been made.The results of this paper can be used for the reference of crack repair analysis and design calculation of the same concrete beam.