Experimental investigation of cross-laminated timber panels subjected to near-field blast loads

Abstract

Research on the performance of structural timber elements subjected to near-field blast loads is lacking, with no known comprehensive experimental studies available to inform design standards and hazard mitigation strategies. This paper presents the results of an experimental test programme investigating the behaviour of cross-laminated timber (CLT) panels subjected to near-field blast loads. Full-scale specimens of varying panel depth were subjected to varying charge weights and standoff distances for the purpose of qualitative and quantitative characterization of behaviour at close-in ranges. Quasi-static three-point bending testing was conducted to establish a baseline in terms of mechanical properties and overall failure modes. When compared to far-field blast loads, the CLT panel specimens were found to be susceptible to localized damage and failure mechanisms, including as surface perpendicular-to-grain damage in compression, as well as delamination of outer laminates, accompanied by significant finger joint failures occurring within the outer laminates. In addition, by comparing quasi-static and dynamic strengths of the experimentally tested specimens, an average dynamic increase factor (DIF) of unity on the resistance was observed.