PREDICTION OF COMPRESSIVE STRENGTH AND KINK BANDS IN COMPOSITES USING A WORK POTENTIAL
PREDICTION OF COMPRESSIVE STRENGTH AND KINK BANDS IN COMPOSITES USING A WORK POTENTIAL
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DOI：
10.1016/0020-7683(94)00158-s
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发表时间：
1995-03-01
影响因子：
3.6
通讯作者：
SCHAPERY, RA
中科院分区：
文献类型：
--
作者：
SCHAPERY, RA
本文描述了一种最近发展起来的表征复合材料非线性非弹性行为的方法，并利用该方法提供了用于单向纤维复合材料抗压强度问题的本构方程。这种基于功势的本构理论，对于预测扭结带角和抗压强度所需的应变状态和应变水平似乎是有效的。然后，描述了纤维波纹度增长的一维变形模型，并使用该模型来说明当局部基体开裂发生且轴向应力等于或超过局部屈曲的预测临界应力时，波纹纤维带引发扭结带的情况。这种对基体开裂的要求用于确定扭结带的角度。对于多轴应力，这个角度和抗压强度取决于整体或平均应力的所有分量；应力的多轴状态可能来自外部载荷或多向层压板中层与层之间的相互作用。建立了以微屈曲为破坏机制的一般面内载荷和任意大几何非线性载荷的预测方程。一个几何近似的解析解也被开发出来。为了说明预测的行为，并表明预测与实验观察是一致的，给出了几个例子的结果。
A recently developed method of characterizing nonlinear, inelastic behavior of composites is described and then used to provide constitutive equations for use in the compressive strength problem of unidirectional fiber composites. This constitutive theory, which is based on a work potential, appears to be valid for the strain state and levels of strain needed to predict kink band angles and compressive strength. A one-dimensional deformation model of fiber waviness growth is then described and used to make a case that a band of wavy fibers initiates a kink band when local matrix cracking occurs and the axial stress equals or exceeds the predicted critical stress for local buckling. This requirement of matrix cracking serves to define the kink band angle. For multiaxial stresses this angle and the compressive strength depend on all components of the overall or average stresses; the multiaxial state of stress may arise from external loading or from ply-to-ply interactions in a multi-directional laminate. Equations are developed for predicting the behavior for general in-plane loading and arbitrarily large geometric nonlinearities when the failure mechanism is microbuckling. A geometrically approximate, analytical solution is also developed. Results for several cases are given in order to illustrate the predicted behavior and to show that the predictions are consistent with experimental observations.