Curosu Iurie, Omara Amr, Ahmed Ameer Hamza, Mechtcherine Viktor
Institute of Construction Materials, Technische Universität Dresden, 01062 Dresden, Germany.
Materials (Basel). 2021 Jun 29;14(13):3631. doi: 10.3390/ma14133631.
The paper presents a finite element investigation of the effect of material composition and the constituents' interaction on the tensile behavior of strain-hardening cement-based composites (SHCC) both with and without textile reinforcement. The input material parameters for the SHCC and continuous reinforcement models, as well for their bond, were adopted from reference experimental investigations. The textile reinforcement was discretized by truss elements in the loaded direction only, with the constitutive relationships simulating a carbon and a polymer textile, respectively. For realistic simulation of macroscopic tensile response and multiple cracking patterns in hybrid fiber-reinforced composites subjected to tension, a multi-scale and probabilistic approach was adopted. SHCC was simulated using the smeared crack model, and the input constitutive law reflected the single-crack opening behavior. The probabilistic definition and spatial fluctuation of matrix strength and tensile strength of the SHCC enabled realistic multiple cracking and fracture localization within the loaded model specimens. Two-dimensional (2D) simulations enabled a detailed material assessment with reasonable computational effort and showed adequate accuracy in predicting the experimental findings in terms of macroscopic stress-strain properties, extent of multiple cracking, and average crack width. Besides material optimization, the model is suitable for assessing the strengthening performance of hybrid fiber-reinforced composites on structural elements.
本文通过有限元方法研究了材料组成及其成分间相互作用对有或无织物增强的应变硬化水泥基复合材料(SHCC)拉伸性能的影响。SHCC和连续增强模型及其粘结的输入材料参数均取自参考实验研究。织物增强仅在加载方向上用桁架单元离散化,本构关系分别模拟了碳纤维织物和聚合物织物。为了真实模拟混杂纤维增强复合材料在拉伸时的宏观拉伸响应和多裂缝模式,采用了多尺度和概率方法。采用弥散裂缝模型对SHCC进行模拟,输入的本构定律反映了单裂缝张开行为。SHCC基体强度和抗拉强度的概率定义及空间波动使得加载模型试件内能够真实地出现多裂缝和断裂局部化。二维(2D)模拟能够在合理的计算量下对材料进行详细评估,并且在预测宏观应力-应变性能、多裂缝扩展程度和平均裂缝宽度等实验结果方面显示出足够的准确性。除了材料优化外,该模型还适用于评估混杂纤维增强复合材料对结构构件的增强性能。