Structural behaviour of deep CLT lintels subjected to concentric and eccentric loading

Cross laminated timber (CLT) has been used in construction for over two decades, mainly in applications such as shear walls under in-plane shear and floors under out-of-plane loads. Interest has recently grown in CLT as an edge-loaded one-dimensional member, in applications such as lintels and floor support beams. In this study, four full-size deep CLT lintels were tested based on a four-point bending test protocol, two in concentric and two in eccentric loading. The vertical and lateral response of the specimens were monitored and analyzed. Compared to the concentrically loaded specimens, a significant decrease in total load resistance was observed in the eccentrically loaded specimens due to the presence of a torsional moment. The failure modes for the concentric and eccentric loading tests were distinguished as flexural failure and shear failure due to torsion, respectively. Widely accepted analytical procedures currently available in literature were used to study the test results and their suitability to the scenarios under investigation was determined. The study provides a basis to evaluate potential analytical procedures for possible future designs where CLT is utilized as deep lintels or beams.