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There were a number of following problems with the values used for design of glulam when loading was parallel to the wide faces of the laminations, such as with oblique angle beams and columns loaded on the “d” face. Note that in this case, according to CSA O86 6.5.2 and 6.5.3, design should be performed as a built-up member using No.2 grade, which is significantly weaker than design using glulam values.
The following problems have been corrected
Fc , Kzc and Kc Used for Axial Design and Combined Axial and Bending Design
The Kzc value in 6.5.8.4.2 and the Kc derived from it in 6.5.8.5 were using the sawn lumber values from 5.5.8. The fc value was also from sawn lumber, although it appeared in the Additional Data table as the glulam value. This resulted in extremely conservative design. It has been corrected, and the axial design values and axial component of combined axial bending now use the glulam values.
Kzv Used for Shear Design
The size factor Kzv was calculated using glulam values when it should have been using sawn, a non-conservative error.
KH Values for Moment and Shear
The program was mistakenly applying a KH value of 1.0, corresponding to glulam, when it should have been applying the system factor for built-up members, a conservative error.
fv Displayed for Shear Design
In the Additional Data table for shear design, the fv displayed was from glulam, but the programming was correctly designing using sawn lumber.
E Displayed for Moment and Shear Design
In the Additional Data table for deflection, the E displayed was from glulam, but the programming was correctly designing using sawn lumber.
Note that a strict reading of these clauses would prohibit the use of the glulam clause 6.5.12 for combined axial and bending, leading to the use of 5.5.10, which refers to 5.5.6 and mandates the use of sawn lumber values for axial components like Fc, Kzc, Kc, and E05. However, to do so imposes too great a penalty on the combined axial and bending design and was not the intention of CSA, according to the Canadian Wood Council. Glulam values used for the axial components of combined axial and bending.