平面应变各向异性本构关系及在应力波传播模拟中的应用

为了研究平面应变条件下各向异性材料中应力波传播的特点,利用各向异性弹性Hooke定律、Tsai-Hill屈服准则、经典塑性流动理论,引入修正的物态方程计及高压下的体积压缩非线性,建立了平面应变条件下正交各向异性复合材料的弹塑性本构关系,并且分析了二维问题中材料变形引起的主轴旋转及客观应力率修正问题。最后采用动态显式有限元方法自行编写程序模拟某种纤维增强复合材料碰撞过程中平面应力波的传播,模拟结果显示,在平面应变条件下应力波在该材料的传播过程中表现出明显的二维效应、各向异性特点及弹塑性特点。

Constitutive relation for anisotropic materials under plane-strain conditions and its application to stress-wave propagation simulation

Toinvestigatethewavepropagationfeaturesinanisotropicmaterialsunderplane-strainconditions,anelastic-plasticconstitutivemodelwasconstructedbycombiningtheHookeslawofanisotropicmaterial,theTsai-Hillyieldcriterion,theclassicfundamentalprinciplesofplasticmechanicsandthemodifiedGrneisenequationofstateconsideringthenonlinearcompressibilityofvolumeathighpressures.Andbasedontwo-dimensionalmaterialdeformation,therotationofmaterialprincipalaxesandthemodificationofobjectivestressratewerediscussed.Thenaself-developed,explicit,dynamic,finiteelementcodewasappliedtosimulatetheplane-stresswavepropagationincertainanisotropicfiber-enforcedcompositesduringcollision.Theresultsshowthatstresswavespropagatingintheabovematerialdisplaytwo-dimensional,anisotropicandelastic-plasticfeaturesunderplane-strainconditions.