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In Design Settings, when the setting for all shear walls on shearline having identical materials was not set to be true, the program was not detecting the violation of condition a of ASCE 12.3.4.2, which is one of two conditions that must be untrue if the redundancy factor is set to 1.3 rather than 1.0. Therefore, dissimilar shear walls, a redundancy factor was never applied to seismic shearline forces when the redundancy input was set to Calculated (rather than 1.0 or 1.3) in the Site Information. This has been corrected.
Note that Calculate redundancy and not to force identical materials are the default settings.
For walls with same materials on both sides of the wall and unknown sheathing thickness, the program assigned zero force to the wall while designing, so that any wall would pass design and there was zero wall deflection. The zero force appears in the deflection results, the shear design results, and no design shear shown at the bottom of the wall in the Elevation view drawing.
Wall parameters related to hold-downs were being included in the definition of standard walls, although they are not part of the material specification intended to be part of a Standard wall: As a result, the following would occur if these were changed for a wall:
The following data were not available for selection in Standard Wall mode, but were being treated as Standard Wall parameters:
The number of end studs, which is used only for hold-down design, has been removed from the standard wall definition for the purpose of design grouping but is retained in the Standard Wall mode of Wall Input View for the purpose of creating default walls.
Hold-down related information is no longer included in the Standard Wall definition because hold-downs are designed separately from walls, and it is desirable to group walls according to wall materials only.
The importance factor used for the maximum and minimum diaphragm design force from ASCE 12.10.1.1 (Eqn.'s 12.10-2 and 12.10-3), and for the out-of-plane of wall Forces using 12.11.10, was always 1.0 rather than the importance factor corresponding to the Risk Category selected in the site dialog.
The incorrect diaphragm design forces were used for drag strut design and appear in the Seismic Information table. The incorrect out-of-plane forces appear in Elevation View.
The program was not applying the unblocked factor Cub from SDPWS Table 4.3.3.2 to the nail slippage term in the non-linear 4-term equation C4.3.2.-1. SDPWS 4.3.3.2 says to divide v in the 3-term equation 4.3-1 by Cub, but there is no direct guidance on whether or how to apply it to the 4-term C4.3.2.-1. The program applied the factor to the shear and bending terms in the 4-term equation, but as the nail slip en term includes v only indirectly, it was not applied to nail slip.
Since Commentary equations C 4.3.2.2.-1 and -2 indicate that it should be considered a stiffness -reducing factor, we decided to divide the deflection due to non-linear nail slip by Cub, rather than apply it to the v before it is raised to a power in the determination of en.
The convergence routine for equalizing deflections along the shear wall as required by SDPWS 4.3.3.4.1 sometimes left a small residual on a segment that should not attract any force, causing the program to report that it could not equalize deflections. The program now zeroes out the force if it is less than 0.05 plf, that is, what appears as 0.00 in the output. Note that it adds this small force back into the pot to be redistributed to other shearlines, so it isn’t leaking forces if several segments are zeroed out.
When determining the shear-through-thickness Gvtv from SDPWS Table C4.2.2A used in the shear term of the 4-term deflection equation in C4.3.2-1, and indirectly via determination of Ga in the 3-term equation 4.3-1, when the sheathing thickness had been left unknown, the program was using the Gvtv for the thickest sheathing option, or 23/32", rather than the thickness for the sheathing being designed. This caused a non-conservative error in the shear term of the 4-term deflection equation of about 5%. The shear term is usually a small component of the overall deflection.