Shockwaves are strong perturbations in aerodynamics that propagate at supersonic speeds independent of the wave amplitude. Physically the occurrence of shockwave is always characterized in a fluid flow by instantaneous changes in pressure, velocity and temperature. In this paper we describe a new wood preservative injection system that has been developed utilizing the non-linear pressure spike behind a propagating shockwave. Preservative treatment of many tropical hard woods and bamboo pose severe problem. Samples (30x2.5x1.00 cm) of an Indian species of bamboo (Dendrocalamus strictus) prepared from defect free culms of dry bamboo are placed in the driven section of the IISc vertical shock tube filled with the 4 % copper-chrome-arsenic (CCA) preservative solution. The bamboo samples are subjected to repeated shockwave loading (3 shots) with typical over pressures of 30 bar in each shot. The results from the studies indicate excellent penetration and retention of CCA preservative in bamboo samples and the method itself is much faster compared to the conventional methods like pressure treatment or hot and cold process.

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