Experimental investigation on impact behaviour of wood-based sandwich structures

International audienceLow carbon emission is a shared goal of all transportation industry. One way to match this expectation consist in the introduction of lightweight materials with high specific properties such as composites materials. Wood based materials combined with fiber reinforced composites appear to be good candidates if we introduce safety considerations and energy absorption capabilities [1]. Additional properties of wood such as fire resistance or thermal and acoustic insulation are also essential for many applications and could lead to a new interest for this old material. Wood is also a totally renewable material which guarantees sustainability with lower costs compared to honeycomb or foam cores [7]. Recent results highlight the advantages of sandwich structures made out of fiber reinforced composites associated with lightweight wood like balsa as a core material for impact applications [2, 3]. This is mainly due to the low cost and high specific properties of wood. Numerous researches have been focused on composite structures while wood-based structures are little studied. Very few applications of wood based sandwich structures were found in automotive [5] and naval structures [4- 6]. In the sixties a “Le Mans” race car designed by Frank Costin (English engineer) was designed with a plywood structure for a total mass of only 450 kg. In this paper, we propose to manufacture and test several sandwich configurations with plywood cores under impact in order to quantify the energy absorption capability of such materials