Influence of Four Ageing Methods on the Mechanical Properties of Bamboo Scrimber

Abstract

In this study, the six-cycle accelerated ageing method (method I), the 6 h boiling-freezing-drying method (method II), the wet circulation method (method III), and the boiling-testing method (method IV), which are accelerated ageing testing methods, were used to study the ageing resistance of bamboo scrimber. Changes in the nail-holding power of the plane, the side, and the end face of untreated/treated bamboo scrimber were analyzed systematically, including other changes in mechanical properties, such as the horizontal shear strength, the modulus of rupture (MOR), and the modulus of elasticity (MOE) along the smooth grain, etc. The results show that all mechanical properties decreased after treatment with the four accelerated ageing testing methods: the nail-holding power decreased by 4%~42% on the plane, 8%~40% on the side, and 5%~66% on the end face. The horizontal shear strength decreased by 3.1%~16.7%, the MOR decreased by 15%~27.2%, and the MOE decreased by 2.6%~12.8%. The nail-holding power of the three sides and the MOR were the most affected properties after treatment. So, the nail-holding power and the MOR can be chosen as important indices to evaluate bamboo scrimber’s weather resistance. For the four accelerated ageing testing methods, the degree of influence on the nail-holding power was in this sequence: method I > method III > method IV > method II. However, after comprehensive consideration, the degree of influence on the mechanical properties was in this sequence: method I > method IV > method III > method II.