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The data in the Displacement da for Deflection – Wood Properties and Construction Details group are for hold-down displacement calculations that cannot be entered independently at each hold-down location.
Default length subject to shrinkage
Used to enter the proportion of the floor depth as input in the Structure input view plus the depth of other wood members, such as wall top and bottom plates, that is subject to shrinkage.
The length subject to shrinkage can be adjusted for individual floors in Structure Input view; these settings are used in creating defaults for new files for the values in Structure Input. You can change these defaults via Save as default for new files.
The first field is the proportion of the floor depth as input in the Structure input view that consists of perpendicular-to-grain wood that is subject to shrinkage. The original default value is .925, corresponding to a 10” nominal wood joist, which combined with .75" flooring material yields the 10" original default floor depth.
The second field is the amount of length subject to shrinkage that is not included in the floor depth. Typically three wall plates for upper stories (4.5"), and one wall plate and a sill plate (3.0") for foundation level. The program applies the same default for all floors, so it may be necessary to adjust one or more levels in Structure View to create different values for foundation and upper stories.
Other (miscuts, gaps, etc.)
Additional sources of vertical shear wall displacement are input here at the discretion of the designer. This could include allowance for studs that are cut too short or without square-cut ends.
Bolt hole tolerance
This is the difference between drilled hole diameter in the studs and the diameter of the horizontal bolt shank. For total-assembly displacements that include slippage, any value greater than 1/16” is added to the published displacement, which includes the effect of standard size bolt holes. This input allows you to take into account the effect of retightening of bolts to create slippage less than 1/16", and oversizing of holes for slippage greater than the standard 1/16".