Posted by Stephen Maloneyover 7 years ago
How does a follow-up expansion work?
*Posted on behalf of a Hilti customer:
1 Reply
Posted by Justin Gloverover 7 years ago
Hi Customer,
well this is a good question. If a torque-controlled expansion anchor, such as the KB-TZ or a HSL-3, is installed in a location where a crack is initiated, the diameter of the drilled hole will increase by a slight amount. When this anchor is loaded in tension under these circumstances, the anchor body of the KB-TZ or HSL-3 will displace through the wedges to make up for the enlargement of the hole, resulting in follow-up expansion. Follow-up expansion essentially means that the anchor will not lose its hold if concrete cracking occurs. I hope I have answered your question. If there is anything else, please let me know.
Best Regards
Justin