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Shrinkage Compensating Device
Indicates that the hold-down a mechanical device to adjust for wood movement, so that the wood shrinkage calculation and wood crush component are not included in the hold-down displacement. When checked, displacement is from fastener slippage and hold-down elongation only.
Always use Elongation at Maximum Capacity
Checking this box will cause the program to use the displacement or elongation at maximum capacity as the vertical hold-down displacement regardless of the force at the hold-down location. Otherwise, the program will factor the displacement by the proportion of actual to maximum force at the hold-down.
This setting was put into the program because manufacturers at one time recommended use of deflection at maximum capacity, however Simpson Hold-down and Tension Tie General Note j. now says "Hold-down deflections may be linearly reduced for design loads less than the allowable load."
It is therefore recommended to leave this box unchecked. If checked, the additional hold-down displacement may create an inaccurate distribution of forces along the shear line. This input will be removed with a future version of the program.