微结构连续损伤理论

本文从微结构理论出发,用相对变形描述微结构之间的微空隙和微裂纹引起的材料损伤的影响,得到用损伤张量描述的各向异性损伤的微结构连续损伤力学理论。该微结构损伤模型可化简为目前公认的几种主要损伤模型:如J.P. Cordebojs和F. Sidoroff的弹性各向异性损伤模型,D. Krajcino-vic和G.U.Fonseka的脆性材料平面裂纹损伤模型,J. Lemaitre的各向同性损伤理论及Kachanov的以面积减少为变量的损伤模型等。作者运用这一理论对混凝土材料的单向拉、压基本受载情形进行了数值分析,并与D. Krajcinovic的损伤模型计算结果及实验结果作了比较,所得结果与实验值比较吻合,特别是在失稳后阶段给出了较好描述,初步表明了本理论的有效性和实用性。

Microstructural Continuous Damage Theory

In this paper, the microstructural continuous damage theory describing ananisotropic damage field is formulated. With various simplifications, thisdamage model can be reduced to a few majar models well known at present,such as the elastic anisotropic damage tensor model presented by J.P. Cordeboisand F. Sidoroff; the planar micro-cracks damage vector model for brittlematterials by D. Krajcinovic; the isotropic damage scalar model by J. Lemaitre,and the unidimensional damage model by L. M. Kachanov. By means of atentative test for the present theory, the author uses it for the analysis of theconcrete specimen under uni-axial tension and compression, as examplified byD. Krajcinovic. The numerical results obtained show good agreement with theexperimental values.