Cross-laminated strand-veneer lumber mass timber panels from commercially produced thermally modified wood strands

Abstract

This study explores the influence of thermal modification on wood strands produced from small-diameter trees and the resulting composite panels, including veneers, laminated strand veneer lumber (LSVL), and cross-laminated strand veneer lumber (CLSVL) mass timber panels. Thermally modified (TM) strands displayed enhanced flatness and thinner mat formation, yielding composite panels with significantly increased internal bond (IB) strength. While TM-strands generally exhibited increased stiffness and reduced strength, these differences are mitigated with the production of veneers, LSVL, and CLSVL using these strands. TM-CLSVL surpassed traditional cross-laminated timber (CLT) in shear performance and eliminated rolling shear failures. Mechanical properties aligned with prediction using the shear analogy method (SAM). The introduction of strand-based technology effectively reduced the thickness swelling of TM-CLSVL by 59%, highlighting its potential for yielding dimensionally stable mass timber products from small-diameter timber. This research underscores the potential for producing mass timber panels using TM wood strands to enhance their durability.