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Under Force-transfer walls, there is a check box called Continuous strap across entire wall.
Continuous Strap
If checked, it is assumed that the force transfer straps and blocking extend in one straight line across the entire wall, so that all central piers extend from the top of the highest opening on the entire wall to the bottom of the lowest opening on the wall. The opening piers and corner piers are also measured from the top of the highest opening and bottom of the lowest opening, so that some sheathing may be contained within the opening area that does not resist shear force. The continuous strap is shown below
Multiple Straps
If unchecked, it is assumed that strapping and blocking exist at the top and bottom of each opening and extend far enough into the adjacent segments to transfer shear force to the central piers. In this case, the central piers extend from the top of the highest of the two adjacent openings, to the bottom of the lowest of the adjacent openings. The opening piers are measured from the top and bottom of each opening. The use of multiple straps is shown below.
In Shearwalls, it is assumed that the strap traverses the entire width of the neighbouring pier, but this is only a recommendation. It is left to the designer's judgment what length of strap and blocking is required to develop the shear force in the pier.
Pros and Cons
The use of non-continuous straps does not provide an advantage in terms of design shear force, as the force developed in the core of the central pier is the same in either case. Strap/blocking forces may be lower as the force is transferred to the central pier in stages, but more strapping and blocking are required due to overlap. The use of this option is recommended only to avoid large strap forces, or if it is more convenient to construct the wall with blocking at the top and bottom of openings.