Authorization Criteria for Stud Type Mechanical Expansion Anchors (MEA) List

Revised: 11/4/2022

Stud Mechanical Expansion Anchors (Stud MEA) shall meet the following criteria for inclusion into the Authorized Materials List (AML).

  • Meets testing requirements in the American Concrete Institute (ACI) 355.2, Qualification of Post-Installed Mechanical Anchors in Concrete. It must have a current International Code Council - Evaluation Service Report (ICC-ESR).
  • The ICC-ESR must indicate that the following criteria are met:
  1. Meets the following minimum tensile strengths:
  • Tensile Yield Strength, fya = 60 ksi.
  • Tensile Ultimate Strength, fu = 90 ksi.
  1. Yielding of the steel element of the Stud MEA is ductile per ACI 318.
  2. Is corrosion resistant, equivalent to AISI Type 304 or AISI Type 316. This includes all parts of the Stud MEA which includes, but are not limited to, anchor body, expansion clip, hex nut(s), and washer(s).
  3. Can be installed in the following locations and situations:
  • Concrete with a compressive strength between 2500 psi and 8500 psi.
  • Without supplemental concrete reinforcement
  • Where concrete cracking may develop
  • Horizontal, vertical, and overhead locations
  1. Can be installed under all weather conditions (Ex., temperature, moisture/saturation, etc.).
  2. When installed, the Stud MEA can:
  • Be loaded under sustained tension
  • Withstand dynamic loading (Ex., wind and seismic)
  1. Meets the criteria in Table 1: Performance Criteria Based on Anchor Diameter.
Table 1: Performance Criteria Based on Anchor Diameter
Diameter (1)

Embedment Depth

hef (3)

Minimum Concrete Thickness

ha (3)


ca,min (3)


s (3)

Wedge3/8"1.5" or more6” or less6” or less3” or less
Wedge1/2"2” or more6” or less4” or less6” or less


  1. The Stud MEA size required (diameter and effective embedment depth) and the structural capacity of an individual Stud MEA anchor or anchor group shall be determined based on ACI 318-14, or later editions. Refer to the Division of Engineering Service’s Structural Design Alert – Anchorage to Concrete, dated 5/11/2020.
  2. The ESR report must include parameters that meet these criteria for a Stud MEA to be on the Authorized Material List (MEA).
  3. See ACI 318.
  4. See Figure 1: Stud MEA Anchor Group.
Figure 1: Stud MEA Anchor Group
Figure 1: Stud MEA Anchor Group

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