ACI-349 Approval for KB-TZ2 Expansion Anchor

Applicability of the KB-TZ2 Anchor
3
August 2021
Purpose and Scope
Hilti has developed a torque-controlled expansion anchor known as the Hilti Kwik Bolt TZ2 (KB-TZ2) for use in concrete and under
static and seismic loadings. The purpose of this document is to evaluate the qualification testing performed on the KB-TZ2 Anchor
System and determine whether it is in compliance with the requirements of ACI 355.2-01 and ACI 349-01 as recognized by the
United States Nuclear Regulatory Commission in USNRC Regulatory Guide 1.199.
A design guide for use of the KB-TZ2 anchor system under ACI 349-01 and USNRC Directive 1.199 is given in Appendix A. All data
in Appendix A meets the requirements of these two documents.
Qualification Testing Program
Testing was ordered by Hilti in 2018 and conducted under the guidance of Luke Tavernit at Element Materials Technology in Saint
Paul, Minnesota. Additional testing was performed at Specialized Testing in Santa Fe Springs, California under the supervision of
Thomas Kolden. All testing was performed according to ICC Evaluation Services Acceptance Criteria for Mechanical Anchors in
Concrete Elements (AC 193), dated October 2017 and editorially revised April 2018.
AC 193 references ACI 355.2 as the base document for the testing and evaluation protocol, adding additional ICC-ES specific
requirements as well as modifications to specific testing and evaluation requirements. Those differences and the resulting anchor
qualification and KB-TZ2 design data will be the focus of this document.
For anchors to be used in facilities under the purview of the USNRC, USNRC requirements must be met. Those requirements are
summarized in Regulatory Guide 1.199. In that guide, ACI 349-01 Appendix B Anchoring to Concrete contains the basic design
requirements for anchoring, and ACI 355.2 is an acceptable testing guide for mechanical anchors.
All submitted testing of the KB-TZ2 expansion anchor system was performed in a satisfactory manner and submitted to ICC-ES for
their review. After review, an evaluation service report (ESR) was issued, ESR-4266, which recognized compliance with AC 193 and
ACI 355.2. ESR-4266 specified the appropriate design data and parameters for use with ACI 318-14, Chapter 17.
Because of differences in evaluation requirements between ACI 355.2-01 and actual testing performed under AC 193, this report
had been prepared to explain and comment on those differences.