考虑横法向热应变的Reddy型功能梯度梁理论

摘要

Reddy型高阶理论已被广泛用于功能梯度材料(FGM)结构分析,然而此理论忽略了横法向应变,难于准确分析功能梯度梁的热力行为.为提高Reddy理论分析热力响应的精度,提出了一种考虑横法向热应变的三参数Reddy型高阶功能梯度梁理论.此模型考虑了横法向热应变,但不增加额外位移变量.应用构建的模型分析了功能梯度梁的热力响应,并研究了不同体积分数对面内应力和位移的影响.数值结果表明,所提出的模型能准确分析功能梯度梁的热力响应,而忽略横法向应变的模型计算结果精度较低.%The Reddy-type higher-order theory has been widely used for analysis of Functionally Graded Material (FGM) structures.However,the theory neglects transverse normal strain,and will thus encounter difficulties in analysis of the thermomechanical behaviors of the functionally graded beam.To improve the performance of Reddy's theory,a Reddy-type higher-order theory considering transverse normal thermal strain with three displacement parameters is proposed.Although transverse normal thermal strain is taken into account,the number of displacement parameters is not increased in the theory.The model proposed is used to investigate thermomechanical response of the functionally graded beam,and also the effect of volume fraction on stress and displacement of functionally graded beam.Numerical results showed that the proposed model can calculate accurately the thermomechanical response of the functionally graded beam,and can improve the calculation ac curacy of the models for transverse normal thermal strain.