A Rupture Limit Equation for Pre-Loaded Laminated Composite Plates

William Schonberg

doi:10.3390/jcs2010003

Abstract

Fiber-reinforced polymer composites offer inherent advantages over traditional metallic materials in a number of different ways; however, these materials are also highly susceptible to impact damage. In this paper, we explore the response of FRP (fiber reinforced polymer) composites under impact conditions that could result in their rupture or catastrophic failure. The work performed was aimed at developing a general, data-driven equation for initially-stressed, flat, composite plates that would differentiate between impact conditions that would result in only a hole or crack and those which would cause catastrophic plate failure or rupture. If this equation were to be subsequently shown to also model the rupture/non-rupture behavior of, for example, composite overwrapped pressure vessels, then it could also be used to appropriately tailor the design parameters and/or operating conditions of such pressurized tanks.

Highlights

Fiber reinforced polymer (FRP) composites offer inherent advantages over traditional materials with regard to their high strength-to-weight ratio, design flexibility, corrosion resistance, low maintenance, and extended service life. These materials are highly susceptible to impact damage, which can result from any number of different low, intermediate, and high velocity impact events
We explore the response of initially-stressed FRP composites plates or panels under impact conditions that are sufficiently energetic so as to result in their rupture or catastrophic failure
The work performed was aimed at developing a general, data-driven equation for uni-axially loaded flat composite plates that would differentiate between impact conditions that would result in only a hole or crack and those which would cause catastrophic plate failure or rupture

Summary

Introduction

Fiber reinforced polymer (FRP) composites offer inherent advantages over traditional materials with regard to their high strength-to-weight ratio, design flexibility, corrosion resistance, low maintenance, and extended service life. In addition to impact studies, other investigations have considered a variety of techniques aimed at strengthening FRP composite materials using carbon nanotubes (see, e.g., [4]), as well as carbon, ceramic, and mineral nanoparticles (see, e.g., [5]) Such studies have typically focused on improving the delamination and fatigue resistance of FRPs by enhancing, for example, their inter-laminar shear strength and fracture toughness. The RLE presented was developed by applying multi-linear regression techniques to data obtained in three recent studies involving uni-axially stressed composite material plates This, is another improvement of the RLE presented over the previous version, which was, in effect, merely a hand-drawn or faired curve between two sets of data points. Since the equation in this paper is statistics-based, it (and the statistics associated with it) can be included in a risk assessment analysis, whereas the previous version could not

Data Overview

Comparison against Empirical Results

Conclusions