| Basic constitutive relations of shape memory alloy and controlling for deformation and vibration of reinforced concrete beam embedded into shape memory alloy wires are studied in this paper.Firstly, by studying and comparing the several constitutive relations of shape memory alloy which is advised at present, the equations of describing martensite interior variable are improved on. Then a new constitutive relation is deduced when alloy wires are restricted during putting back. The new constitutive model is more simple and fit for application in engineering. At the same time, relation between stress and temperature of alloy is simulated by program and compared with the results of experiment. The precondition of theory is offered for studying deeply.Then, In normal temperature, Ni-Ti shape memory alloy (SMA) wires are elongated beyond their plastic limit and are eccentrically embedded in reinforced concrete beam, using especial shape memory effect of SMA, upon heating the alloy, a martensite-to-austenite phase transformation takes place and the material will undergo large shrinkage deformation, because deformation of alloy is districted by concrete, large shrinkage stress is produced, the concrete beam will be actuated. In this thesis, finite element program ANSYS is used to simulate the concrete beam precisely. By analyzing the deformation, stress status and inherent frequency of reinforced concrete beam. The conclusion is obtained, SMA can be utilized to induce additional prestressing in concrete beam, to enhance the intensity and rigidity, the aim of active control of deformation and vibration is achieved finally.
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