WIT-SHB Filling Washer for optimizing shear load distribution among anchors in an anchor group
When fasteners loaded in shear are relatively close to a concrete edge, failure can occur in the form of concrete edge breakout. Quantifying the shear strength of an anchorage against concrete edge breakout is well covered in AS5216 and is largely dependent on edge distance and concrete strength. In addition, AS5216 conservatively specifies that only the row of anchors closest to the edge are to carry the applied shear load, as illustrated below. This is to conservatively account for the clearance between anchor and steel plate. The capacity of an anchorage against concrete edge breakout can be improved by increasing the number of anchors near the edge or distributing the shear load among anchors more effectively.
While increasing the number of anchors near the edge is a good solution, it is often not feasible. The other approach is to ensure that shear loads are distributed among all anchors. This can be done by ensuring that the annular space between steel plate and fastener are filled with a filling material that has enough compressive strength to effectively and simultaneously transmit the shear load from the steel plate to the fastener. The Wurth WIT-SHB is a filling washer that aids in effectively filling the annular space with high strength epoxy or mortar. The video shown below illustrates how it works.
WIT-SHB Filling Washer compatible with a number of Wurth Anchors
The WIT-SHB filling washer can be used with a number of Wurth Anchors, as shown in the following illustration.
Wurth Anchor Design Software & Annular Space
The option to fill the annular space is also covered in the Wurth Anchor Design Software as illustrated below.
Need more information?
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