Aisi E 1 Volume Ii Part Vii Anchor Bolt Chairs Better May 2026

AISI E-1, Volume II, Part VII provides a globally recognized framework for designing anchor bolt chairs

2. Critical Design Parameters

Anchor bolt chairs are structural assemblies welded to the base of shells (such as storage tanks, silos, or tubular columns) to transfer uplift loads from anchor bolts into the shell. They are essential because they prevent the shell from buckling or overstressing at the base plate connection. aisi e 1 volume ii part vii anchor bolt chairs better

A. Superior Fatigue Resistance

Common issue:

Oversized or slotted holes are used to allow column placement after concrete pour, but excessive slot length reduces bearing area and introduces bending in the bolt. AISI E-1, Volume II, Part VII provides a

Minimum steel yield strength: 33 ksi (but use 50 ksi for seismic).
Chair legs must be cold-formed channels with web stiffeners if L/t > 200.
Welds shall comply with AWS D1.3, with E70XX electrodes.
Provide certified mill test reports and structural calculations stamped by a professional engineer.
Hot-dip galvanize per ASTM A123 after fabrication."

: Proper chair design provides "stretch length" for the anchor bolt, allowing it to yield under extreme loads (like seismic events) rather than fracturing prematurely. Rigid Box Structure Minimum steel yield strength: 33 ksi (but use