In FY 2016, the Oregon State University College of Forestry's Institute for Working Forest Landscapes awarded approximately $550,000 in funding to the TallWood Design Institute to launch four research projects that will enhance understanding of wood building structures. In March 2017 a review process involving architects, structural engineers, wood products manufacturers and research scientists selected eight more projects to commence in Spring 2017 and $1.25M in funding. Projects were selected based on their ability to deliver actionable results to industry (designers, manufacturers, building code officials, building contractors) to address current challenges and potential opportunities in the wood construction sector.
Net-Zero Energy TallWood Design
This project aims to solve one of the biggest barriers to increased market adoption of mass-timber buildings - energy consumption. The project team will explore how to replace the concrete typically needed for night flush cooling of thermal mass. The goal is to provide results that will help mass-timber buildings achieve net-zero energy priorities for a larger range of use types and climate zones while also providing new insight into human perception of thermal comfort in mass-timber buildings.
The Pulse of the Global CLT Industry: Launching an Annual Survey as a Continuing Learning Tool
This project explores the emerging cross-laminated timber industry in other countries to learn the key success factors, challenges, business models and level of government support other countries receive in order to better implement the use of CLT in the U.S. The outcomes will include a database, annual reports on the CLT industry and specific guidelines for facilitating sustainable growth in the modern U.S. forest products industry.
Design of the Timber Pile Ground Improvement for Liquefaction Mitigations
Liquefaction caused damage to 25,000 homes in the 2011 Tohoku earthquake in Japan and $15 billion in losses in Christchurch in 2010-11. This project creates design guidelines for the use of timber piles driven into the ground as a way to protect building foundations from soil liquefaction in seismic events. This approach has application in protecting a broad range of other structures, including port and harbor facilities, bridge approach embankments and foundations.
Seismic Performance of Cross-Laminated Timber and Cross-Laminated Timber-Concrete Composite Floor Diaphragms
This project develops benchmark data needed to generate design guidelines for structural engineers to calculate strength & stiffness of CLT-diaphragms, with and without concrete toppings. The project includes a full-scale test of a two-story mass timber building at the UC San Diego shake table in collaboration with the larger project, “Development and Validation of a Resilience-based Seismic Design Methodology for Tall Wood Buildings” which features collaborators from throughout the western US and is funded by the Natural Hazards Engineering Research Infrastructure (NHERI) program of the National Science Foundation.
Living Lab at Peavy Hall: Structural Health Performance of Mass Timber Buildings
Building on the results of an earlier project that established protocols for post-occupancy building monitoring, this project aims to install a system in the new Peavy Hall building at Oregon State University to monitor moisture, relative humidity, vertical and slip movements due to shrinkage & deflection, post-tensioning losses, vibration and seismic activity. The monitoring system will establish a “living” laboratory that demonstrates in real time how the mass timber components of the building are affected by various internal and external phenomena. The data will be gathered and analyzed over the service life of the building.
Composite Concrete-CLT Floor Systems for Tall Building Design
This project will optimize the strength, stiffness, vibration characteristics, acoustic qualities and fire resistance of cross-laminated floor systems utilizing a composite concrete and cross-laminated timber product. This project includes development, testing and optimization of an economical shear connector (to connect the CLT panel to the concrete slab) that will be compared with existing screw and steel plate solutions. The resulting prototype floor system will be tested at full scale.
Life Cycle Analysis of Old- and New Peavy Hall
This project assesses and compares the environmental impacts of forest products used in the old (1999) Peavy Hall teaching building at Oregon State University and the new mass timber building that will be completed in 2018. The findings will be incorporated in updated guidelines for life cycle analyses that fully take into account the role of reclaimable wood building products.
Tall Wood Buildings and Indoor Air Quality
New research is showing that wood buildings are more likely to harbor environmental microbes with beneficial health effects. This pilot project will study various surface materials in both the lab setting and occupied mass timber buildings to assess effects on occupants’ health and comfort as well as indoor air quality.
Behavior of CLT Diaphragm Panel-to-Panel Connections with Self-tapping Screws
Understanding how roof and floor systems (commonly called diaphragms by engineers) that are built from Pacific Northwest-sourced cross-laminated timber (CLT) panels perform in earthquake prone areas is a critical area of research. These building components are key to transferring normal and extreme event forces into walls and down to the foundation. The tests performed in this project will provide data on commonly used approaches to connecting CLT panels within a floor or roof space and the performance of associated screw fasteners. Structural engineers will directly benefit through improved modeling tools. A broader benefit may be increased confidence in the construction of taller wood buildings in communities at greater risk for earthquakes.
Cross-Laminated Timber Fasteners Solutions for Tall Wood Buildings
Constructing buildings with CLT requires development of novel panel attachment methods and mechanisms. Architects and engineers need to know the engineering strength properties of connected panels, especially in an earthquake prone area. This project will improve knowledge of three types of wall panel connections: wall-to-floor, wall-to-wall, and wall-to-foundation. Testing will determine the strength properties of metal connectors applied with different types and sizes of screw fasteners. The data will be used to develop a modeling tool that engineers can use when designing multi-story buildings to be constructed with CLT panels.
Structural Health Monitoring and Post-Occupancy Performance of Mass Timber Buildings
A key question about new generation taller wood buildings is how they will perform over time in terms of durability and livability. This project will determine how best to measure these qualities by selecting sensors, determining testing and measurement protocols, and implementing testing assemblies in selected CLT buildings in Oregon. Future research will use the knowledge developed through this project to carry out post-occupancy monitoring, generating valuable new insights into building performance.
Fire Performance of Douglas-fir CLT Wall and Floor Assemblies Made in Oregon
An important area of concern for building code officials is fire safety, and there is very little data in the U.S. that documents the performance of CLT panels exposed to fire. This project will document the flammability of Douglas-fir and spruce-pine-fir CLT panel assemblies produced in the United States. Tests are being conducted on wall and floor panel assemblies with standard overlapping connections and produced with two different types of commonly-used adhesives. Sensors placed throughout panels will provide data about how fire affects the interior and exterior of a panel. A thermal imaging camera will provide information on how the structural integrity of panels is affected by fire and fire suppression activities.