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Released October 29, 2014 with Design Office 9, SR-1b
Important Note – These are descriptions to changes implemented in version 9.1 and may not reflect current program behaviour.
Despite the fact that CSA O86 5.5.4.2.1 and 6.5.6.3.1 say that beams must be laterally supported at points of bearing, several users have indicated that they would like to design beams that are either not laterally braced at interior points of bearing or that are insufficiently laterally supported, in their engineering judgement, and therefore consider the full beam length as the unsupported length Lu for the calculation of the KL factor.
Noting that mechanics of the buckling equations used to derive the KL factor require only that the beam be fixed against rotation at two points, and that the American Wood Council Technical Report 14 includes a multi-span beam example with unsupported length as the entire length of the beam, Sizer has been modified to allow the choice of whether a beam is or is not laterally supported at interior supports.
A checkbox Laterally supported at support has been be added to the Supports for bearing and notch design box. It behaves similarly to the Bearing where support ends or is highly stressed checkbox in terms of being checked, unchecked, disabled and enabled when multiple supports are selected at once in the Applies to box.
The program ensures that end supports and cantilever supports are always checked, to maintain two points at the end of each beam that are fixed against rotation.
The existing output under the materials specification in the Design Check summary which says "at supports", has been modified to say "at all supports", "at end supports", or e.g. "at supports 1,2, 4."
If the checkbox is not checked, the program does not consider the interior support when determining the unsupported length Lu. If " At supports" is chosen as the lateral support option, all interior supports are unchecked, the program uses the full beam length as the unsupported length. If a lateral support spacing greater than a span length adjacent to such as support, the lateral support length is used instead of the span length.
If the option "Use zero moment points" is selected as well as unchecking lateral support as a support, the distance between zero moment points to the left and right of the support is used if it is greater than any span length.
Starting with version 8, Concept mode was inadvertently doing bearing design using the dimensions of supporting members as bearing lengths, and rejecting possible sections if they failed bearing design. However, it did so imperfectly as follows:
This capability has been removed until such time that a comprehensive treatment of bearing design can be implemented in Concept mode.
For version 9 of the program, interior notches were implemented for sawn lumber and glulam, despite the fact that glulam members are not allowed to be notched in the interior according to the Commentary to O86 clause 6.5.7. This has been corrected by disabling the input of notches at interior supports for glulam members.
If a point load located close to the end of beam followed a partial uniform line load, partial uniform area load, triangular load, or a trapezoidal load in the sequence of input loads, the point load was deleted when the other beam dimensions like bearing length, span length, span type, etc were changed. This has been corrected.
When a member which is supported by multiple ply members was exported from Concept mode to beam or column mode, the program assumes the supporting member has only one ply when assigning a bearing width. Instead, it should assign an unknown bearing width, as plies are not input into concept mode groups and the program assumes plies are unknown.
Note that the program does not export the widths or depths of supporting members as they were designed by concept mode - if they were unknown in concept groups, then they are unknown in the exported member. A future version of the program may export the designed supporting member information.
Although the ability to change the load duration factors KD was removed from the Sizer settings for version 2002, the lines representing the default values were not removed from the .sizer.ini file until version 9. If a sizer.ini file retained from version 8 or earlier was manually edited, the program used the changed KD factors for design. It was also possible to change them, so they were out of range, causing messages to pop up and disable the proper functioning of load input.
The program no longer allows KD factors to enter the program from edited sizer.ini files.
The program now records the version of the program used to save a project file and shows it in the About Sizer box when the file is opened. This feature is primarily used internally at WoodWorks for diagnostics.
The terminology in beam view "Support length or _____ has been changed to Notch length… support length = bearing length
In database editor, the Mr, Vr and mass values for certain steel beams are displayed as 0 even though non-zero values were available and used in the Sizer program. This has been corrected
Because Windows no longer supports the Windows XP operating system, it was necessary to create the folder C:\Users\Public manually on XP systems in order for the installation of Sizer to work. This has been corrected and this folder is now created by our installation program, and Sizer can be installed on XP systems. As XP is still used by 15-20% of Windows users, WoodWorks continues to support this operating system.