Mechanically graded wood materials have been added for the AWC NDS 2015 design code per Table 4C, and CSA O86-14 design code per tables 6.3.2 and 6.3.3. This specification includes the updated MEL and MSR design values.
A Mechanically Graded material can be selected in the Material spreadsheet in the Wood tab. The user can choose any of the existing species that are applicable, per NDS table 4C Footnote 2, from the Species dropdown menu. The shear capacity design value, Fv, depends on the species selected for the material. There are 85 new grade options available in the Grade dropdown menu from the MSR and MEL tables in the code.
The Custom Wood Properties dialog now allows the user to input more specific material. Mechanically Graded wood materials can be utilized in this dialog by choosing MEL or MSR in the Type dropdown menu. To access the Custom Wood Properties input dialogue, click the Custom Wood button on the Advanced tab.
This can also be accessed In the Wood Material Properties spreadsheet by selecting Custom from the Type dropdown menu, and then click the ellipses in the Species cell.
Additionally, a custom wood size factor can now be entered in the CF entry in the Custom Wood Properties dialog box. If CF is left blank, RISA will automatically calculate the factor for you per the NDS 2015 equation in Table 4D.