PFI-RP: Manufacture of Durable and Stable Cross-Laminated Strand-Veneer Lumber for Mass Timber Construction

The broader impact/commercial potential of this PFI project is in development of a commercially-viable process for manufacturing high-performing, durable mass strand timber panels for building construction from low-value and underutilized small-diameter softwood trees, such as from hazardous fuel thinning operations for improved forest health. The broader impacts are: (1) advancement of discovery and understanding while promoting teaching, training, and learning by including students and faculty in the research; (2) enhancement of infrastructure for research and education by establishing collaborations between interdisciplinary, yet complementary academic and industry stakeholders; (3) broadening of research dissemination to enhance understanding by involving industry and academia in the research, publishing project results in diverse media sources, and presenting research results in several formats that will benefit a wide range of forest products industry stakeholders; and (4) improved economic competitiveness of the U.S. forest products industry. In addition, if this proof-of-concept research leads to commercial applications, the benefits to society are: (1) new products with reduced environmental impacts, improved durability, and longer service-life; (2) technology that increases the U.S. forest products industry's competitiveness through creation of new jobs and increased opportunities for potential exports; and (3) increased use of wood, an environmentally-friendly, renewable, sustainable, and carbon-sequestering material.The proposed project addresses challenges facing cross-laminated timber (CLT) panels in mass timber construction. Construction currently requires extreme care to protect CLT panels from moisture while ensuring long-term durability. Although builders take measures to reduce moisture exposure, it is inevitable that the CLT panels will take on water during their service-life. This project addresses these problems by utilizing thermal modification to produce chemical-free, mass timber panels with increased resistance to moisture and decay and improved dimensional stability. The goals are to: (1) evaluate process-performance relationships for thermal modification of small-diameter wood strands, and (2) demonstrate the feasibility of manufacturing high-performance cross-laminated strand-veneer lumber (CLSVL) mass timber panels. The objectives are to: (1) demonstrate the feasibility of utilizing thermally modified laminated strand veneer lumber for production of high-performance CLSVL panels, and (2) determine the potential environmental impacts of the new CLSVL panels. The technical results include validation of a repeatable process for thermally modifying small-diameter pine strands, validation of a method for manufacturing CLSVL panels, verification of physical and mechanical performance of the CLSVL panels, and establishment of commercially-viable process-performance relationships to enable commercial production of the CLSVL mass timber panels.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.