Computational modeling of high performance steel fiber reinforced concrete using a micromorphic approach
Computational modeling of high performance steel fiber reinforced concrete using a micromorphic approach
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DOI：
10.1007/s00466-013-0873-4
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发表时间：
2013-12
影响因子：
4.1
通讯作者：
A. Huespe;J. Oliver;D. Mora
中科院分区：
文献类型：
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作者：
A. Huespe;J. Oliver;D. Mora
提出了一种模拟具有任意取向短纤维的高性能纤维增强混凝土复合材料（HPFRC）破坏的有限元方法。复合材料模型是基于微观形态的方法。利用该理论提供的框架，通过两个运动学描述子来描述人体的位形空间。在结构层次上，位移场表示标准的运动学描述符。此外，一个形态运动学描述符，微观领域，介绍。它描述了在细观尺度上观察到的纤维-基体相对位移或粘结的滑动机制。在本文的第一部分中，我们总结了作者在以前的工作中提出的微观方法的模型制定。在第二部分中，作为本文的主要贡献，我们解决了与模型的计算实现中涉及的数值方面有关的具体问题。开发的数值计算程序是基于混合有限元技术。每个节点的自由度的数量根据复合材料中模拟的纤维束的数量而变化。然后，提出了一种具体的解决方案，以解决离散模型中未知数的可变数量。HPFRC复合材料模型考虑了混凝土断裂产生的重要影响。在模型中引入了一种模拟准脆性断裂的方法。目前的数值方法进行评估，通过模拟一组选定的实验测试，证明其可行性和准确性，以捕捉一些力学现象的相互作用，在宏观和细观尺度，并导致失败的HPFRC复合材料。
A finite element methodology for simulating the failure of high performance fiber reinforced concrete composites (HPFRC), with arbitrarily oriented short fibers, is presented. The composite material model is based on a micromorphic approach. Using the framework provided by this theory, the body configuration space is described through two kinematical descriptors. At the structural level, the displacement field represents the standard kinematical descriptor. Additionally, a morphological kinematical descriptor, the micromorphic field, is introduced. It describes the fiber–matrix relative displacement, or slipping mechanism of the bond, observed at the mesoscale level. In the first part of this paper, we summarize the model formulation of the micromorphic approach presented in a previous work by the authors. In the second part, and as the main contribution of the paper, we address specific issues related to the numerical aspects involved in the computational implementation of the model. The developed numerical procedure is based on a mixed finite element technique. The number of dofs per node changes according with the number of fiber bundles simulated in the composite. Then, a specific solution scheme is proposed to solve the variable number of unknowns in the discrete model. The HPFRC composite model takes into account the important effects produced by concrete fracture. A procedure for simulating quasi-brittle fracture is introduced into the model and is described in the paper. The present numerical methodology is assessed by simulating a selected set of experimental tests which proves its viability and accuracy to capture a number of mechanical phenomenon interacting at the macro- and mesoscale and leading to failure of HPFRC composites.