Behaviour of mass timber members subjected to consecutive blast loads

Abstract

This paper presents the results of an experimental and analytical investigation into the behaviour of full-scale glued-laminated timber (glulam) beams and cross-laminated timber (CLT) panels subjected to consecutive shock-tube-simulated blast loads. Superficial crack development was observed in the glulam specimens even when loaded within their elastic range. However, these cracks did not appear to affect the overall stiffness and strength of the specimens, as proven through subsequent loading and verification of the experimental resistance curves. Extensive propagation of rolling shear damage was prevalent within the transverse layers of the CLT specimens once flexural failure initiation occurred. Following significant rolling shear damage, the composite nature of the CLT panels were observed to degrade, corresponding to a loss of stiffness and strength. An equivalent single-degree-of-freedom (eSDOF) modelling methodology, capable of taking into consideration the dynamic behaviour of both specimen types and damage accumulation due to subsequent loading, is presented and validated using the experimental test data.