Interfacial shear strength studies using the single‐filament‐composite test. Part II: A probability model and Monte Carlo simulation
Interfacial shear strength studies using the single‐filament‐composite test. Part II: A probability model and Monte Carlo simulation
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DOI：
10.1002/pc.750100603
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发表时间：
1989-12
影响因子：
5.2
通讯作者：
R. B. Henstenburg;S. Phoenix
中科院分区：
文献类型：
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作者：
R. B. Henstenburg;S. Phoenix
建立了蒙特卡罗模拟方法，为解释单丝复合材料试验数据提供了基础。主要重点是开发一种改进的程序，以达到纤维-基质界面的剪切强度的真实值，但也显示了如何使用该测试来表征纤维的强度分布，其长度比标准张力测试所能达到的要短得多。该仿真基于广泛使用的光纤失效泊松/威布尔概率模型，该模型以沿光纤分布的随机缺陷来表征强度。纤维端应力积累的主要力学模型与大多数作者所假设的相同，并假设在这个剪切传递区有一个恒定的界面剪切应力，使人联想到屈服的塑性基体。然而，我们也考虑了一个双线性模型，该模型允许一个具有恒定剪切应力的脱粘区，低于主“塑性”区。模拟结果以无量纲变量的形式进行，并制成表格，以便广泛适用。还讨论了样本量和置信区间问题。
A Monte Carlo simulation is developed to provide a foundation for interpreting experimental data from the single-filament-composite test. The main focus is on developing an improved procedure for arriving at a realistic value for the shear strength of the fiber-matrix interface, but it is also shown how the test may be used to characterize the strength distribution of fibers at a length scale much shorter than is achievable in standard tension tests. The simulation is based on the widely used Poisson/Weibull probability model for fiber failure that characterizes the strength in terms of the random flaws distributed along the fiber. The primary mechanical model for stress buildup at the fiber end is the same as that assumed by most authors and assumes a constant interfacial shear stress in this shear transfer zone reminiscent of a yielding plastic matrix. We also, however, consider a bilinear model that allows for a zone of debonding with a constant shear stress lower than in the primary “plastic” zone. Simulation results are cast in terms of nondimensional variables and tabulated to allow for wide applicability. Sample size and confidence interval issues are also discussed.