Impact behaviour of preloaded glass/polyester woven plates

Abstract

In this work, the effect of a biaxial preload in the behaviour of glass/polyester woven laminate plates subjected to high velocity trans versal impact was studied. For this, an analytic model based on energy considerations that include the presence of an in plane preload was used. The results of the analytic model for the biaxial preload state were compared with those found for a non preload plate, the difference between them being minimal for the pre stressed level reached in the tests (31% of the static UTS). Therefore, numerical simulations were made in order to study the effect of the preload in greater detail; furthermore, experimental tests were conducted, validating the analytic and numerical model. In general, the two methods revealed minimal differences between the values of the ballistic limit and those of the residual velocity.

Experimental analysis of normal and oblique high velocity impacts on carbon/epoxy tape laminates

“…In the next decade the number of articles regarding high velocity impacts on carbon/epoxy laminates grew substantially, and not always the main focus was experimental, many of them had a numerical [16][17][18][19][20][21] or an analytical point of view [22][23][24][25][26], which is not the main porpoise of the current work.…”

Influence of shear plugging in the energy absorbed by thin carbon-fibre laminates subjected to high-velocity impacts

“…Shear-plug formation is not observed for thin glass-reinforced composites [8]. Such mechanisms as matrix or delamination failure are less relevant than fibre failure, especially in thin glass-reinforced laminates [7,8,11], for which the energy absorbed by fibre deformation and failure, and laminate acceleration, are the main mechanisms [7,8,11]. In thick glass-reinforced laminates, delamination and matrix-crushing mechanisms could be a relevant energy-absorption mechanism.…”

“…Also the relevance of each mechanism could change with impact velocity. Usually, for thin laminates, friction and heating are negligible [7]. Shear-plug formation is not observed for thin glass-reinforced composites [8].…”

“…), formation of a shear plug, friction, heating, etc. [7,8]. The relative importance of each mechanism depends on the material, plate thickness, and laminate configuration, as well as on the projectile geometry and size [9,10].…”

“…An analytical model, based on energy consideration was applied to study this problem. This model is based on the one proposed by García-Castillo et al [7,23], initially developed for GFRP woven laminates. The model applied in this work incorporates an energy-absorption mechanism due to shear plugging.…”