A local sensitivity based multiscale stochastic stress analysis of a unidirectional fiber reinforced composite material considering random location variation of multi fibers
A local sensitivity based multiscale stochastic stress analysis of a unidirectional fiber reinforced composite material considering random location variation of multi fibers
复制标题
考虑多纤维随机位置变化的单向纤维增强复合材料的基于局部敏感性的多尺度随机应力分析
DOI：
10.1115/1.4043400
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
S. Sakata and T. Sakamoto
中科院分区：
文献类型：
--
作者：
S. Sakata;Y. Chan and Y. Arai;S. Sakata and T. Sakamoto
本文描述了一种有效的计算方法，用于估计单向纤维增强复合材料中的最大微观应力的概率特性，以对抗纤维位置的微观随机变化。一些微观几何随机变化将引起微观应力的大的变化，即使对均匀化的弹性性能的影响很小。细观应力的随机变化将对复合材料的表观强度产生重要影响，因此，对细观应力随机变化的估计对于复合材料结构的可靠性设计具有重要意义。此外，为了更精确的分析，应采用包含许多夹杂物的晶胞。当随机变量的数量变大时，基于多点近似的方法将不合适。因此，本文提出了一种计算方法与一个连续的灵敏度分析构造的局部代理。用逐次灵敏度局部代理估计细观应力的实现，用Monte Carlo模拟中的近似实现估计应力的概率性质。作为算例，考虑纤维位置的随机性，对单向纤维增强复合材料板在沿着横向单向拉伸载荷作用下进行了多尺度随机应力分析。对于这个问题，概率性质的期望和变异系数的树脂中的最大微观应力估计。通过与直接蒙特卡罗仿真结果的比较，讨论了该方法的有效性和可行性。
This paper describes an efficient computational method for estimating the probabilistic properties of the maximum microscopic stresses in a unidirectional fiber-reinforced composite material against microscopic random variations of fibers locations. Some microscopic geometrical random variations will cause a large variation of the microscopic stresses, even if the influence on the homogenized elastic properties is small. The random variation of the microscopic stresses will have a significant influence on the apparent strength of composites, and therefore, estimation of the random variation will be important for reliability-based design of a composite structure. Further, for more precise analysis, a unit cell containing many inclusions should be employed. When the number of random variables becomes large, a multipoint approximation-based approach will not be appropriate. Therefore, a computational approach with a local surrogate constructed by a successive sensitivity analysis is proposed in this paper. The realizations of the microscopic stresses are estimated with the successive sensitivity-based local surrogate, and the probabilistic properties of the stresses are estimated with using the approximated realizations in the Monte Carlo simulation. As an example, the multiscale stochastic stress analysis of a unidirectional fiber-reinforced composite plate under unidirectional tensile load along the transverse direction is performed with considering randomness in fibers locations. For this problem, probabilistic properties as the expectation and coefficient of variation of the maximum microscopic stresses in resin are estimated. From comparisons between the direct Monte Carlo simulation and the proposed method, validity and effectiveness of the proposed approach are discussed.