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Important Note – These are descriptions to changes implemented in WoodWorks Shearwalls for version 10.0 and may not reflect current behavior
Previously, if you wanted to generate All Heights Case 2 loads (75% loading plus 15% moment – Figure 27.4-8) for torsional analysis with the rigid diaphragm procedure, you had to use these loads in a separate design run and manually compare the resulting design to determine the critical case. The program was not capable of generating Case 1 and Case 2 simultaneously, or using the worst of these cases for design.
Now the program generates both Case 1 and Case 2 loads and uses the heaviest loading from each of these cases and the minimum load case as the design shearline force on each line.
The Design Setting allowing you to choose between Case 1 and Case 2 wind loads has been removed; the program now generates loads and distributes forces for both these cases at all times.
Previously, changing the show menu between Case 1 and Case 2 triggered a regeneration of loads, prompting you to accept the new loads. Now it merely shows the existing loads and forces for the selected design case on the screen.
Previously, when you added a load, or added a direct shearline force with “Both” selected as the force distribution method, with Case 2 selected in the Design Settings, Case 1 loads at 100% Case 2 loads at 75% were created. Case 1 loads were restricted to flexible diaphragms. If Case 1 was selected, only Case 1 loads at 100% were created.
Now, both Case 1 and Case 2 loads and forces are always created when a load or force is added. The added loads apply to both rigid and flexible diaphragms (see Related Features, below). The added shearline forces apply to the selected force distribution method, rigid or flexible.
The program performs rigid and flexible diaphragm distribution for both case 1 and case 2 load cases, and uses the largest resulting shearline force as the design force. This is done before any design or any intra-shearline distribution, similar to the way it currently chooses the worst of several low-rise wind load cases.
The minimum loads are distributed independently for rigid and flexible diaphragms, creating two separate sets of shearline forces
For the all-heights procedure, rigid diaphragms, the program previously gathered the loads to distribute by taking all the loads on levels above the level being designed. This is in contrast to the low-rise and seismic procedure that uses the flexible diaphragm forces on the floor above. These methods are mathematically equivalent.
This was done because the rigid diaphragm procedure required 75% loads, but the flexible procedure required 100% loads. As this is no longer the case, for rigid diaphragms, the program uses flexible diaphragm forces on the floor above for all load cases.
Previously, both Case 1 and Case 2 loads were shown only when Case 2 is selected, now they are shown all the time.
The load case showing in these tables is now the critical one for design, and can be different for each shearline. Previously, each entry in the table showed the case selected in the Design Settings
Note that the load case is not shown in the Shear Results tables due to space limitations, so that the hold-down and drag strut tables can be used to infer which load case was used for shear design.
In the torsional analysis section, rigid diaphragm analysis is now be repeated for Case 1 and Case 2, indicated by e.g. E->W and N->S WIND DESIGN (CASE 1)