This index is a compilation of connections used in mass timber construction. Mass timber elements are solid wood pieces with inherent fire resistance due to their mass, as defined in the 2021 International Building Code (IBC). Examples of mass timber include but are not limited to cross laminated timber (CLT), dowel-laminated timber (DLT), nail-laminated timber (NLT), glue-laminated timber (GLT), mass plywood panels (MPP), and structural composite lumber (SCL) products such as laminated veneer lumber (LVL) and laminated strand lumber (LSL). Mass timber can be used as structural floors, roofs, walls, columns and/or beams. The examples in this index illustrate a broad spectrum of connections for use in mass timber construction. Depending on the unique constraints of each project, the connection choice made by the designer may be influenced by aesthetics, load carrying capacity, fire-rating requirements, quality assurance requirements, cost and/or constructability. The purpose of the index is to facilitate the designer’s selection of project appropriate connections.
The George W. Peavy Forest Science Complex, or “Peavy Hall,” is a mass-timber university building that is the subject of a structural health monitoring (SHM) program to create a comprehensive building performance dataset. The building substructure consists of cross-laminated timber (CLT)-concrete composite floors, a mass plywood panel (MPP) roof system, and the world's first application of CLT post-tensioned (PT) self-centering shear walls. This document reports on static and hygrothermal data collected during the final ten months of building construction that were used to validate a proposed methodological approach to SHM for mass-timber buildings under construction, described in A Methodological Approach for Structural Health Monitoring of Mass-Timber Buildings Under Construction . These data, available in the repository at https://osf.io/jdz6y/, include wood moisture content of CLT, MPP, and glulam structural components, horizontal and vertical displacements of axially loaded CLT panels, tension loss of PT steel rods within CLT self-centering walls, and indoor and outdoor environmental conditions such as temperature, relative humidity, rain quantities, wind speeds, as well as wind directions. Additionally, data figures and analysis coding files are included in the repository to further define processes and allow for potential use of the analysis tools for similar projects.
Wood-based mass-panels (WBMP) are emerging as an attractive construction product for large-scale residential and commercial construction. Australia is following the lead of Europe and North America with several recent projects being completed using predominately cross-laminated timber panels (CLT). These sawn timber-based panels offer some key advantages to the construction and sawmilling industry. However, veneer-based mass-panel (VBMP) systems could offer additional benefits including the more efficient use of the available forest resources to produce WBMPs that have equivalent to superior performance to CLT. Research to confirm the expected technical viability of veneer-based systems is required. VBMPs could provide a valuable contribution, alongside CLT, to the Australian timber products market.
Every material has an environmental footprint. Mass Plywood Panel, a new entrant in the mass timber category, has the potential to revolutionize the mass timber sector. The environmental consequences of producing Mass Ply Panels (MPP) are carried forward into the life cycle of products made from it, such as wooden structures. Life cycle inventory (LCI) data cover forest regeneration through to final product at the mill gate. There is over 20 years of life cycle assessment (LCA) research on major US produced forest products, both structural and nonstructural, from four major regions.
This report describes the cradle-to-gate (mill) energy and materials required for producing MPP produced in Oregon and the subsequent releases into the environment. The environmental impacts, global warming, ozone depletion, acidification, smog, and eutrophication are discussed.
Buckling Restrained Brace Frames (BRBF) are a proven and reliable method to provide an efficient lateral force resisting system for new and existing structures in earthquake prone regions. The fuse-type elements in this system facilitate stable energy dissipation at large load deformation levels. Currently, the new trend towards mass timber vertical...
Project contact is Shiling Pei at the Colorado School of Mines
NHERI Tallwood project is an effort to develop and validate a resilient-based seismic design methodology for tall wood buildings. The project started in September 2016 and will last till 2020. The project team will validate the design methodology through shake table testing of a 10-story full-scaled wood building specimen at NHERI@UCSD. It will be the world's largest wood building tested at full-scale.
Project contact is Mark Fretz at the University of Oregon
University of Oregon and Oregon State University are collaborating through TallWood Design Institute (TDI) to upgrade aging, energy inefficient and seismically unprepared multifamily housing by developing a mass plywood (MPP) retrofit panel assembly that employs digital workflows and small diameter logs (down to 5") to create an economically viable energy/seismic retrofit model for the West Coast and beyond. The project has broad potential to support forested federal land management agencies and private forestry by proving a new market for small diameter logs.
Project contact is Kevin Van Den Wymelenberg at the University of Oregon
Our aim is to support the acceptance and increase market share of sustainable mass timber construction technologies such as Cross Laminated Timber (CLT), Mass Plywood Panel (MPP), Glue Laminated Timber (GLT), and Nail Laminated Timber (NLT), by lowering or eliminating barriers due to lack of acoustics data for mass timber construction assemblies. Currently, sustainable mass timber projects carry the cost of required acoustics testing, impairing their economic feasibility. With our new acoustics testing facility, testing supported by this grant will produce common acoustics data on the assemblies most in market demand. These data will be hosted in an online open-access database, supporting rapid growth in this industry. Increasingly specialized testing scenarios will be more easily accommodated, as this facility is located closer to USFS source materials and production facilities than currently operating facilities and is designed specifically for the specialized requirements of testing mass timber assemblies. Since sustainable mass timber technologies allow increased utilization of lower quality timber, and timber with insect damage, increasing the market share of mass timber will increase utilization of USFS timber, specifically that which might otherwise remain on-site unused. With removal of this type of timber, fire load will be lessened as well. Initial testing supported by this grant will include mass timber assemblies constructed with lower quality and smaller dimension timber.