Unlocking the Benefits of Mass Timber Construction
As environmental sustainability becomes increasingly important, pioneering construction methods are leading the way to a greener future.
Traditional steel and concrete construction methods are labour-intensive, involve lengthy construction schedules, and result in a significant carbon footprint. The development of mass timber construction methods addresses these challenges by speeding up the construction process, while obtaining higher fire safety ratings and decreasing the carbon footprint. Also, according to Natural Resources Canada, mass timber designs offer renewability, carbon emission reduction through carbon sequestration, and more accurate dimensional tolerances compared to traditional construction methods.
Validating Greencore's Rapid Building Solutions
Greencore Structures has developed a new seismically resilient assembly system using a mass plywood panel product. This product is designed to enable rapid construction of stackable elevator and stair shaft structures for multi-story buildings. These new mass plywood panels have the potential to increase building safety and significantly change how mass timber buildings are constructed, especially in regions with high seismic activity.
The materials and connections Greencore is using are proprietary and not listed in any Building Code tables. To validate the new technology for commercial development, Greencore required a performance-based design approach that was jointly endorsed by an Engineer of Record and a Peer Review Engineer. To meet these requirements, Greencore conducted several rounds of custom testing in the full-scale structural testing laboratory at C-FER Technologies in Edmonton, Alberta, Canada. The first testing program was designed to understand the failure limits of the wood component of the mass plywood panel under extreme loading conditions.
Mass Timber & the Future of Construction
This two-part podcast series explores the transformative potential of mass timber in modern construction, and the role C-FER Technologies played in testing its limits.
Part One
Discover how mass timber is reshaping the way we build. This episode dives into the material’s sustainability, strength, and the new opportunities it brings to the construction industry.
Part Two
Learn about C-FER Technologies’ full-scale testing of Greencore Structures’ panel system. The results highlight the remarkable strength of mass timber and underscore the importance of rigorous engineering evaluations in advancing construction technology.
How Greencore Worked with C-FER
From the outset of their collaboration, Greencore and C-FER focused on creating a stringent and unbiased scientific testing framework for Greencore’s mass plywood panel technology.
Three full-scale specimens, each weighing approximately 8,000 pounds with the steel connections, were tested on C-FER’s Strong Floor using a series of portable hydraulic actuators and a purpose-built structural reaction frame. Custom-made fixtures were required to connect the specimens to the testing system in two different configurations. A LabVIEW-based test control and monitoring system provided precise control of the load sequences and robust monitoring of the test instrumentation.
Testing Mass Plywood Panels
Test 1: Pure Shear Test
Greencore tested a new structural material, which is essentially volumetric plywood 1-ft thick, together with proprietary connections, which attach steel to the mass timber. The strength of the material was predicted by the manufacturer; however, it had never been tested at full-scale.
Greencore’s Series 1 Tests demonstrated the strong promise of this material for shear wall applications in multi-story buildings. To create pure shear loading, an arrangement involving three hydraulic actuators and three stiff links was developed.
Test 2: Cyclic Loading Test
Greencore developed a connection system that includes disc springs and viscous pads, which operate together similar to the springs and shocks of a car. The resiliency of this connection system needed to be demonstrated with cycles of reversing loads. Greencore and C-FER jointly designed a test configuration and procedure for cyclic load application similar to how loads would reverse during a seismic event.
By capacity-protecting Greencore’s system to keep the loading below the damaging level, fully resilient buildings can be designed in which no structural damage occurs during a seismic event. Understanding these load limits helps enable Greencore to achieve this goal.
Test 3: Transverse Tension Test
In both of the previous tests, there was no damage observed to Greencore’s full-scale wood panels; therefore, it was necessary to conduct a final test to failure of the wood of the panel system to determine the over-strength available in the wood. In other words, Greencore wanted to “break it to make it!” by going beyond the loading scenarios that had been achieved during the prior tests.
Greencore and C-FER determined that the specimens used in the Series 2 tests could be modified and combined and would be able to fit vertically in C-FER’s Universal Testing System (UTS).
Leverage C-FER's Experience & Third-party Perspective
C-FER Technologies works with operating companies to push the limits of engineering constraints to improve performance of existing assets, develop new resources, and evaluate and implement new technologies for energy transition. We partner with companies to address challenges such as structural design, integrity and risk management, quantitative risk assessments, and defect evaluation.
C-FER provides full-scale equipment testing and qualification, risk management, and engineering consulting services. Our structural analysis capabilities include modelling non-linear behaviour and large strain challenges. Our testing facilities accommodate a wide range of specimen sizes and testing scenarios, including internal and external pressure, bending, and axial loads.
About Greencore
C-FER Technologies works with operating companies to push the limits of engineering constraints to improve performance of existing assets, develop new resources, and evaluate and implement new technologies for energy transition. We partner with companies to address challenges such as structural design, integrity and risk management, quantitative risk assessments, and defect evaluation.
C-FER provides full-scale equipment testing and qualification, risk management, and engineering consulting services. Our structural analysis capabilities include modelling non-linear behaviour and large strain challenges. Our testing facilities accommodate a wide range of specimen sizes and testing scenarios, including internal and external pressure, bending, and axial loads.
Contributor
Brian Wagg, MSc, PEng.
Director, Testing Services
With over 35 years with C-FER, Brian Wagg’s current focus is on applying C-FER’s analytical and full-scale testing capabilities to projects in clean energy including CCUS, hydrogen, geothermal and small modular nuclear reactors.
