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For the bearing design of the bottom plate of a wall introduced with version 9, the bearing length used in bearing factor CB calculations was the width d of the wall stud rather than its thickness b, even though the thickness is reported as the bearing length used. The thickness is now used, as it is the parallel-to-grain dimension.
As a result, the CB factor for a 3.5” stud was 1.12, and for a 5.5” stud was 1.02, rather than the correct 1.25 for a typical stud thickness of 1.5”.
Note that this applies only when the box for Bearing at support end is unchecked, otherwise CB is 1.0.
This problem was introduced along with bearing design for user-input supports in Version 9.
The following refinements have been made regarding the designation of repetitive member for different member types, and the application of the system factor Cr.
For sawn lumber and SCL beams, the program now allows you to specify that it is part of a system of repetitive members, with Repetitive member unchecked by default. You check it only if you know that the beams are to be spaced not more than 24” apart, in which case the Cr. factor is applied. If a beam is designated as repetitive, a design note appears in the output giving the required spacing.
For glulam members used as a joist, the program now disables the repetitive member checkbox and sets it to unchecked, as the NDS does not include a Cr factor for glulam joists. Note that glulam joists can only be entered into Sizer by creating a new database file in Database Editor.
The output specification of the repetitive member choice now appears in the output for SCL materials, previously it was missing.
When the width of a glulam beam is narrower than the depth, so that there is a CL factor, and the beam is loaded on the weak axis, the program was using the Ey,min for the beam lateral stability factor CL (NDS 3.3.3), but should be using Ex, min. This has been corrected.
When columns are loaded axially and laterally, the program outputs the Emin or Emin,y value used for combined axial and bending design only, even though a different one may have been used for axial design or for the calculation of the CP lateral stability factor, in which case the choice depends on column slenderness ratio. Now, if both Emin and Emin,y are used, they are output on separate lines in the output report. If only Emin,y is used, it is shown as Eminy, whereas it used to just say Emin.
When designing unknown sections with notches, if the section examined for design does not pass the restrictions based on maximum notch depth, but earlier ones did, the program crashed. This happened despite the fact that larger sections will not violate the notch restrictions if smaller ones didn't, because the program proceeds to examine shallower sections that are wider, and sections made from different materials.
For this reason, this problem occurred intermittently, for example inputting ¼” as the notch depth is fine, inputting 3" causes a crash, and inputting 6" results in a message that it cannot find a section, which was correct given the notch restrictions.
This has been corrected.
When using metric units, the IBC fire endurance calculated by the program was 25 times smaller than it should be, that is, 2-3 minutes instead of 60+ minutes when in imperial.
The program now allows beams to be supported by walls in beam mode, in order to take into account the compressive resistance of a wall top plate. Wall supports are still not allowed for beams in concept mode; a column usually representing built up wall studs must be embedded in the wall.