
Increased Strength of HemFir (N) Expands Structural Application in Heavy Timber Construction
February 21 @ 10:00 am - 11:00 am
| FreeAIBC 1 Core LU
An in-grade testing program on HemFir (N) timbers, conducted by the University of British Columbia Timber Engineering and Applied Mechanics (TEAM) Laboratory, evaluated 1,212 full size specimens in static bending and 921 specimens in small, clear tests. Significant increases in the specified bending strength fb of HemFir (N) ranged from 14% for the select structural grade to 53% in the No.2 grade. Based on the in-grade test results, the Canadian Code on Engineering Design in Wood CSA 086:19 has published new specified bending strength properties of HemFir (N) Beams and Stringers grades.
The increased specified bending strength properties of HemFir (N) Beams and Stringers grades opens up opportunities for structural application of the product. For example, comparing the specified strength properties of HemFir (N) to Douglas Fir-Larch Beams and Stringers, the No.2 HemFir (N) material (fb=14.4 MPa and E=11 GPa) exceeded the No.2 Douglas Fir-Larch material (fb=9.0 MPa and E=9.5 GPa) significantly.
In this session we will look at how the HemFir (N) code change by the CSA 086 Technical Committee on Engineering Design in Wood, the Canadian Standard, opens up more selection opportunities for designers and expands the structural application of HemFir (N) material in heavy timber construction. More specifically, we will look at a comparison of Pacific HemFir, Douglas Fir and comparable engineered wood products.
This session will be presented by an senior Professor of Wood Building Design and Construction in the Department of Wood Science at the University of British Columbia.
Learning Objectives:
- Understand how in-grade testing works and why it matters
- Review the impact of in-grade testing on the strength properties of lumber products
- Recognize the technical performance, sustainability and versatility of HemFir Timbers in different applications
- Discover new applications for HemFir (N) with a comparison to Douglas Fir and comparable engineered wood products