We utilized the Hilti Kwik bolt TZ stainless steel to secure rigid conduit with uni struts to a CMU wall. This located at John Wayne Airport in Orange county, CA. the contractor drilled and the set the wedge anchors about 1.5" from the head joint. In looking at ESR 4561 page 9 reflects a detail for "hollow" head joints vs "solid grouted" head joints. since the CMU wall is existing and we cannot confirm if the head joints are hollow or solid, do you have a reduced value for the wedge anchor with the edge distance that is less that the min of 2.5"
Hi Jacob,
Thank you for reaching out. As you mention, the minimum distance from the center of the KB-TZ2 to the center of a hollow headjoint is listed in Table 2 of ESR-4561. In cases where anchors are installed with a dimension below this minimum, Hilti does not have published test data to support any specific reduction value. When minimum geometrical constraints are not met, a significant concern is failure of the base material itself – for example, masonry splitting – upon installation and loading.
As the application is outside of Hilti’s published parameters, it is ultimately at the discretion of the Engineer of Record on the project to deem if the anchorage is sufficient. On-site testing may aid in that judgement.
For additional inquiries, please reach out to hnatechnicalservices@hilti.com.
Kind regards,
Sinan