Wood as a structural material for transportation industry: Past example and recent advances

Bruno Castanié (1) , Romain Guélou (1) , Arthur Cantarel (1) , Samuel Rivallant (1) , Florent Eyma (1)

1 ICA - Institut Clément Ader

Wood was the primary material in aviation until World War II [1]. We can mention the famous Mosquito nicknamed "the Wooden Wonder". Its structure is made up of sandwich panels with skins formed from birch plies and a balsa core. It was manufactured in 7781 samples, with a "one shot" half-fuselage production and could reach 612 km/h. Until the 1990s, the Mudry CAP10 acrobatic aircraft was made entirely of wood. There is also a recent version of this aircraft with a carbon wing spar known as the CAP10BK. Today, the Aura Aviation company [2] is once again offering a French wood carbon aerobatic aircraft. In the automotive sector, only the English Morgan offers cars with an ash superstructure but an aluminum chassis. At Le Mans 1967, the Costin-Nathan has a plywood wooden frame, the doors are in fiberglass and it weighs only 410 kg [3]. This brief and non-exhaustive historical reminder questions the intrinsic capacities of wood, especially if it is combined with current materials. This is why the members of the ICA started working on the subject in 2014. The studies focused on the manufacturing methodologies and the static response of plywood- based sandwiches with skins made of glass fibers, carbon fibers, flax fibers or aluminum [4]. These sandwiches were then subjected to impacts [5] and their compressive strength after impact was analyzed [6]. A first attempt of modeling was also carried out [7] and above all showed that the problem requires a lot of investigation. The very good compression characteristics observed convinced us to launch a second thesis still in progress on the crash. This area is particularly important because automobiles are sized according to the HIC (Head Injury Criteria), a criterion which establishes the maximum deceleration that a human being can withstand during a collision without having irreversible consequences. A first publication was recently accepted [8] which shows that poplar (one of the lightest temperate woods, very present in France and affordable) has an SEA (Specific Energy Absorption) of between 20 and 30 KJ / kg while the carbon is between 30 and 80 kJ / kg, while poplar veneers cost 40 times less. Tests with other species (oak, walnut, etc.) and with a carbon / poplar mix will also be presented

Domaines: Matériaux et structures en mécanique [physics.class-ph]

Bruno Castanié, Romain Guélou, Arthur Cantarel, Samuel Rivallant, Florent Eyma. Wood as a structural material for transportation industry: Past example and recent advances. 24th International Conference on Composite Structures Faculty of Engineering, University of Porto, Portugal, Jun 2021, Porto, Portugal. ⟨hal-03407651⟩