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Important Note – These are descriptions to changes implemented in WoodWorks Shearwalls for version 10.3 and may not reflect current behavior.
To allow you to identify walls and hold-downs that fail design without having to scan the full design results report, the program now includes a design summery. It appears in the Design Results report before the shear results for the first design case (just after the loads are output). In addition, the program alerts you with a pop-up message if any walls fail.
If any walls fail for any design case ( rigid diaphragm, flexible diaphragm, wind shear, wind C&C, seismic), the program shows a message box on the screen that gives the levels and he design cases that the failure occurs. It tells you to go to the Design Results or to see the highlighted walls in Plan View (see Feature 75, above)
For each design case (wind shear loads - rigid diaphragm, wind shear loads - flexible diaphragm, components and cladding wind loads - out-of-plane sheathing, components and cladding wind loads - nail withdrawal, seismic loads - flexible diaphragm, seismic loads - rigid diaphragm) the design summary either indicates that there were no under-capacity walls, or gives a list on each level of the names of the shearlines with walls that failed.
For each design case (wind shear loads - rigid diaphragm, wind shear loads - flexible diaphragm, , seismic loads - flexible diaphragm, seismic loads - rigid diaphragm) the design summary either indicates that there were no under-capacity hold-downs, or gives a list on each level of the names of the walls that contained under-capacity hold-downs.
The Go to Table menu that appears when the Design Results are shown now includes an item for Design Summary.
In designing for groups and for worst case design, the program considered only shear strength when determining whether a wall should be used as the design wall, not taking into account nail withdrawal or out-of plane sheathing strength for C&C loading.
As a consequence, for wind design, a wall designed for the interior of the structure with field nail spacing that renders it too weak for out-of-plane loads could be chosen as the design wall because it is stronger for shear than an exterior wall that was designed for C&C loads. .
Similarly for worst case design, the program could choose as a wall designed for seismic loading as the worst case wall, but it too leaves the field nail spacing at the largest value and may fail for wind suction on the exterior surface. A wall designed for wind on the exterior surface is was not chosen as the design wall. because the seismic wall had a larger shear resistance.
This was solved by tracking the worst-case design for nail withdrawal and for out-of plane bending. If the wall chosen for shear design had weaker solutions for unknown parameters than the walls designed for withdrawal or out-of-plane, the program replaces those parameters in the design wall with the ones designed for C&C loading.
The procedure has one slight imperfection in that thicker sheathing, which is optimal for out of plane sheathing strength and for shear design, makes for weaker nail withdrawal strength due to reduced penetration. So when determining the strongest wall, one wall may be stronger for out-of-plane design and for shear but another may be stronger for nail withdrawal. In such a case, the program uses the wall with thicker sheathing. It is extremely rare for the wall to fail for nail withdrawal as a result
When changing a standard wall designed as a group for a wall on a line with multiple walls, the program changed the standard wall for only that wall, retaining the old standard wall for other walls. However, it changed the materials for all the walls on the line to the ones for the new standard wall group, because all shearwalls on a shearline must have the same materials.
As a consequence, when the program then designed for that shearline, it designed for both the new and old standard wall groups using the materials for the new standard wall group. However, the previous standard wall group has different materials on other shearlines in the building. Therefore a single standard wall group could be designed for different sets of material selections, and would show different sets of material specifications in the user input, contrary to the intended purpose of standard walls designed as a group.
This has been corrected and a standard wall designed as a group now has just one set of material specifications.
The program was applying the unblocked factor Cub for 16" spacing to stud spacing other than 16". The correct factors from SDPWS Table 4.3.3.2 are now applied. .
Starting with version 9.1, all sheathing capacities for out-of-plane C&C design were mistakenly multiplied by 1.5/1.6, so that the sheathing capacities were 93.75% of what they should be. This has been corrected.
Starting with version 10.2, for those shearlines that do not extend to the exterior perimeter of the building, the length of the shearline was taken to be the distance between the start of the first wall and the end of the last, ignoring the gaps between the extreme wall ends and the exterior of the structure.
For lines with a gap between the end and the perimeter walls, the problem was manifested in the following ways;
If there are multiple entries for hold-down capacity for different stud widths, and the entries are listed with the larger stud width before the smaller width and the wall’s stud width is greater than both entries, the program used the capacity and elongation for the smaller stud width even if the larger width was the closer match. This has been corrected
If you selected a hold-down that is not rated for the thickness of wall studs at the end of the wall, then the program did not design for that hold-down and it used the displacement over-ride entered in the settings. It issued a warning in the hold-down design and hold-down displacement tables to that effect.
Since the wall studs do not necessarily include "cripple" or "jack" studs beneath the window that can contribute to hold-down strength, the program now issues a warning to the effect that extra cripples or jack studs are needed, and continues with hold-dow design using the capacity and displacement for the least thick stud assembly that the hold-down is rated for. The warning is no longer in red indicating a failed design.
For some projects, when drywall screws are used, the program assigned zero capacity to shearlines composed entirely of gypsum wallboard, issuing a warning under the shear design table indicating that it is outside seismic design category restrictions even if it was within those restrictions, and it did this for wind design to which SDC’s don’t apply.
This was caused by the program internally assigning nail size of 5 to 5/8" gypsum wallboard. This has been corrected, and size 6 is applied to this material, but for existing project files, the problem could still occur. It can be corrected by manually selecting size 6 and re-designing. .