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CSA O86 11.4.4 allows for shear walls to be designed to resist overturning using either hold-down connections or anchorages at the ends of each shear wall segment.
Hold-downs
A hold-down connection typically consists of a steel bracket bolted or nailed to the shear wall end studs, connected by a threaded rod and an end stud to either the foundation or to a bracket on the lower level wall (refer to O86 Figure 11.4(a) or CWC Wood Design Manual (WDM) Fig. 8.7). The overturning force is transferred from the top chord directly to the tension end-stud to the wall or foundation below. Since the sheathing is not used to transfer the overturning tension force, all the sheathing strength strength can be devoted to shear resistance.
Anchorages
An anchorage is a threaded rod installed within 300 mm of the segment end connecting the wall bottom plate to the foundation or to the top plate of a lower level shear wall segment (refer to O86 Figure 11.4(b) or WDM Fig 8.8). Since the tension end stud is not directly tied down, the overturning force must be transferred to the bottom plate through the sheathing. The full strength of the sheathing cannot therefore be considered as contributing to shear resistance. To account for this, O86 requires that a Hold-down Effect Factor Jhd, be applied to reduce the design shear strength of shear wall segments for which anchorages are provided instead of hold-downs.
Input
Refer to Hold-down Configuration ffor options that allow you to place hold-downs vs. anchorages at wall segment ends, and to Wall Design Iteration for a description of the cycle in the design process that attempts to ensure passing design by replacing anchorages with hold-downs in the event of failure.