Design Mercer Glulam to CSA O86

Mercer’s Canadian glued laminated timber is manufactured by OK Laminators (dba Mercer Mass Timber, Okanagan Falls, British Columbia). It is recognized under APA Product Report PR-L351(C). SPEC Toolbox designs the beams and columns to CSA O86, in limit states design.

The integration covers the OK Laminators glulam, manufactured to CSA O122 in two species groups, grouped by grade.

Douglas Fir-Larch

• 24f-E and 24f-EX (bending), 18t-E (tension) and 16c-E (compression).

Spruce-Lodgepole Pine-Jack Pine

• 20f-E and 20f-EX (bending), 14t-E (tension) and 12c-E (compression).

Sections run to 760 mm wide, 1900 mm deep and 29.9 m long. Uses include beams, headers, rafters, purlins and columns.

At a glance, in the Canadian scope the OK Laminators glulam supports:

• Beams and columns.
• Limit states design (LSD).
• Dry service, with wet-use factors available for wet conditions.

• Two species groups. Douglas Fir-Larch (relative density 0.49) and Spruce-Lodgepole Pine-Jack Pine (0.42), so the species can be matched to the load and the connection demand.
• Bending, tension and compression grades. Balanced (-EX) and unbalanced (-E) bending grades to 30.6 MPa, plus dedicated tension (18t-E, 14t-E) and compression (16c-E, 12c-E) grades.
• Very large sections. Sections reach 760 mm wide, 1900 mm deep and 29.9 m long, for long-span beams and heavy columns.
• Fire resistance to two hours. Exposed members may be designed for fire exposure up to 2 hours by Annex B of CSA O86, with the rating evaluated per NBC Appendix D-2.11.

The OK Laminators glulam members are available across the SPEC Toolbox member-design modules, worked to CSA O86:

• Timber beam and Timber column.

and in the connection modules:

• the screw connection module and the CLT floor-to-glulam beam connection.

Member behaviour is taken from the integrated database with the LSD specified strengths of PR-L351(C), using the species relative density (Douglas Fir-Larch 0.49, spruce-pine 0.42) for fastener design.

Design follows CSA O86 (CSA O86:19, limit states design) under the National Building Code of Canada. APA Product Report PR-L351(C) publishes LSD specified strengths in MPa for the OK Laminators glulam, manufactured to CSA O122: bending, longitudinal shear, compression parallel and perpendicular, tension at net and gross section, tension perpendicular to grain, and modulus of elasticity. Factored resistances are obtained with the CSA O86 modification factors, among them the load-duration, service-condition and size factors; bending values are for loads applied perpendicular to the wide faces, with minor-axis bending designed per CSA O86 Clause 7.5.3. Tabulated values are for standard-term duration and dry service, with property-specific wet-use factors for wet conditions; fire is designed by Annex B of CSA O86, for up to 2 hours.