Quasi-Static Compression and Low-Velocity Impact Behavior of Tri-Axial Bio-Composite Structural Panels Using a Spherical Head

Abstract

This paper presents experimental results of both quasi-static compression and low-velocity impact behavior for tri-axial bio-composite structural panels using a spherical load head. Panels were made having different core and face configurations. The results showed that panels made having either carbon fiber fabric composite faces or a foam-filled core had significantly improved impact and compressive performance over panels without either. Different localized impact responses were observed based on the location of the compression or impact relative to the tri-axial structural core; the core with a smaller structural element had better impact performance. Furthermore, during the early contact phase for both quasi-static compression and low-velocity impact tests, the panels with the same configuration had similar load-displacement responses. The experimental results show basic compression data could be used for the future design and optimization of tri-axial bio-composite structural panels for potential impact applications.

A Study on the Failure Mechanisms of Composite Laminates Simultaneously Impacted by Two Projectiles

“…Matrix compressive failure mode (σ 22 +σ 33 )<0 (4) Here σ ij is the stress component referred to the principal axes x 1 x 2 x 3 , X T , X C , Y T , Y C , represent, respectively, the tension and compression strength along and perpendicular to the fibre direction which is along the x 1 -axis. The shear strength in either the x 1 x 2 -plane or the x 1 x 3 -plane is denoted by S, the S 23 represents the shear strength in the x 2 x 3 -plane.…”

“…After the satisfaction of the damage initiation criterion, the interface stiffness is gradually degraded by a scalar damage variable D. The stress components are expressed by a function of the damage variable as (6) tensile and compressive failure and matrix tensile and compressive failure [9]. The proposed viewpoint is that the damage initiates when one of the four indices ( 1,2,3,4) f    just exceeds 1.0. After damage initiation, a stiffness degradation rule can be used to access the progressive damage behaviour of composite laminates.…”

“…Composites are particularly susceptible to the foreign impact loads because of their poor properties in the through thickness direction, so the study of structural response and damage process of composites under impact loads is important. Most studies reported in open literature [1][2][3][4][5] have addressed the single point isolated impact event with relatively little discussion related to the multi-site impact. Compared with single point impact, more complicated damage mechanism such as the interaction of internal damage induced by each projectile will change the global structural response and damage process experienced in the multi-site simultaneous impact.…”

Damage tolerance of carbon and Kevlar based hybrid composites against quasi-static indentation

“…Damage mechanism and failure modes were characterized and results indicated that failure mechanism was expressively affected by stacking sequence of fibers as well as fibres type. Jinghao Li et al [3] conducted experimentation on both quasi-static and low velocity impact for investigation of impact behavior of tri-axial bio-composite structural panels. The core of panels made with foam and face sheets are made with carbon fibers.…”