一种描述木材受压的非线性本构模型及试验验证

发布时间：2018-08-18 13:05

【摘要】：在一种用于纤维复合材料的简易本构模型的基础之上,通过考虑木材在纤维方向产生的塑性应变并假设木材是横观各向同性材料,提出了一种包含双参数的弹塑性本构模型。该本构模型采用一种二次多项式形式的屈服函数,假设材料的塑性应变从加载开始即逐渐产生,并定义了有效应力和有效塑性应变来反映材料所固有的非线性性质。为了确定本构模型中的待定参数,同时验证该本构模型针对木材的适用性,进行了不同纤维角度红松材的静力受压试验。通过对比模型的预测结果与受压试验结果发现,该双参数本构模型能够较为准确地反映木材受压的非线性应力-应变关系,可以用来预测木材在斜纹理方向受压时的力学行为。
[Abstract]:Based on a simple constitutive model for fiber composites, a two-parameter elastoplastic constitutive model is proposed by considering the plastic strain of wood in the fiber direction and assuming that the wood is transversely isotropic. The constitutive model uses a yield function in the form of quadratic polynomials and assumes that the plastic strain of the material is gradually generated from the beginning of loading. The effective stress and the effective plastic strain are defined to reflect the inherent nonlinear properties of the material. In order to determine the undetermined parameters in the constitutive model and verify the applicability of the constitutive model, the static compression tests of Korean pine wood with different fiber angles were carried out. By comparing the prediction results with the compression test results, it is found that the two-parameter constitutive model can accurately reflect the nonlinear stress-strain relationship of wood under compression, and can be used to predict the mechanical behavior of wood under oblique texture compression.
【作者单位】：北京交通大学;
【基金】：国家自然科学基金优秀青年基金项目(51422801);国家自然科学基金重点项目(51338001);国家自然科学基金面上项目(51178028) 北京自然科学基金重点项目(8151003)
【分类号】：TU531.1

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