A New Approach toward Understanding Damage Mechanisms and Mechanics of Laminated Composites Due to Low-Velocity Impact: Part II

Abstract

An investigation consisting of both analysis and experiments was performed to study impact damage mechanisms and mechanics of laminated composites subjected to low-velocity impact. In order to fundamentally understand the impact damage of laminated composites, a unique test program was developed and performed by using a specially designed line-loading impactor. Experimental findings from the tests were obtained and presented in the first part of this series on the impact study. In this paper, an analysis will be presented for predicting the impact damage resulting from the line-loading impact and for determining essential parameters governing the impact damage. The model consists of a transient dynamic finite element analysis for calculating stresses, strains and deformations of composite plates during impact, and a failure analysis for predicting the threshold of impact damage and initiation of delaminations and micro-cracks. The predictions based on the analysis agreed with the test results reasonably well. Based on the unique approach, the proposed analysis, coupled with the experiment, was able to provide comprehensive information for fundamentally understanding the impact damage mechanisms and mechanics of laminated composites.

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A New Approach toward Understanding Damage Mechanisms and Mechanics of Laminated Composites Due to Low-Velocity Impact: Part II—Analysis

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