Nonlinear behavior of composite sandwich beams in three-point bending
Nonlinear behavior of composite sandwich beams in three-point bending
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DOI：
10.1007/bf02323195
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发表时间：
2001-06-01
影响因子：
2.4
通讯作者：
Abot, JL
中科院分区：
文献类型：
--
作者：
Gdoutos, EE;Daniel, IM;Abot, JL
研究了复合材料夹层梁在三点弯曲作用下的荷载-挠度行为。梁由单向碳/环氧面板和聚氯乙烯闭孔泡沫塑料芯材制成。绘制了直至破坏起始点的荷载-挠度曲线。它们由初始的线性部分和后面的非线性部分组成。建立了考虑面板和芯材的非线性行为(材料非线性)和梁的大挠度(几何非线性)共同作用的材料非线性力学分析方法，理论预测与试验结果吻合较好。研究发现，在短跨度情况下，材料非线性对梁的挠度的影响对于剪切为主的核心层破坏更为明显。这是由于岩心的非线性剪切应力-应变行为造成的。对于大跨长度，观测到的非线性很小，这是由于面板非线性应力应变行为和梁的大挠度共同作用的结果。
The load-deflection behavior of a composite sandwich beam in three-point bending was investigated. The beam was made of unidirectional carbon/epoxy facings and a polyvinyl chloride closed-cell foam core. The load-deflection curves were plotted up to the point of failure initiation. They consist of an initial linear part followed by a nonlinear portion. A nonlinear mechanics of materials analysis that accounts for the combined effect of the nonlinear behavior of the facings and core materials (material nonlinearity) and the large deflections of the beam (geometric nonlinearity) was developed, The theoretical predictions were in good agreement with the experimental results. it was found that the effect of material nonlinearity on the deflection of the beam is more pronounced for shear-dominated core failures in the case of short span lengths. It is due to the nonlinear shear stress-strain behavior of the core. For long span lengths, the observed nonlinearity is small and is attributed to the combined effect of the facings nonlinear stress-strain behavior and the large deflections of the beam.