The Simpson Strong-Bolt 2 1/4 in. x 3-1/4 in. Wedge Anchor in zinc-plated carbon steel is a wedge-type expansion anchor engineered by Simpson for high-performance anchoring in concrete and masonry. Built to maintain reliable holding power under static, seismic, and high-wind loading, the Strong-Bolt 2 features dual undercutting embossments on each clip segment that enable secondary expansion should a crack form and intersect the anchor location - significantly increasing the ability of the anchor to carry load if the hole expands. Tested per ACI355.2 and AC193, this anchor is qualified for seismic design categories A through F and supports horizontal, vertical, and overhead installations.

Key Features

• Dual undercutting embossments on each clip segment - enable secondary expansion if a crack intersects the anchor, so the anchor continues to carry load even as the hole expands, maintaining structural integrity in demanding conditions.
• Chamfered top design - prevents mushrooming during installation, protecting the fastener head and making post-installation cleanup faster and easier.
• Qualified for seismic design categories A through F - covers the full range of seismic risk classifications, giving engineers and contractors confidence in code-compliant installations for both static and seismic loading conditions.
• Suitable for horizontal, vertical, and overhead applications - provides installation flexibility across a wide range of structural anchoring tasks without requiring multiple anchor types.
• Tested per ACI355.2 and AC193 - independently verified performance standards mean contractors and inspectors can rely on documented, traceable load data.
• Zinc-plated carbon steel construction - provides a corrosion-resistant finish appropriate for interior concrete and masonry anchoring applications.
• Installs with a 1/4 in. drill bit and 7/16 in. wrench size - compatible with standard tools already on the job site, keeping installation straightforward and efficient.

Why This Product

• Engineered for cracked and uncracked concrete alike - the secondary expansion mechanism provided by the dual undercutting embossments means performance is not compromised if concrete cracks at the anchor location, making this a sound choice for structurally critical connections.
• Full seismic qualification across all design categories - with coverage from seismic design category A through F, this wedge anchor suits projects in virtually any seismic zone, reducing the need to source specialty fasteners for high-risk regions.
• Versatile installation orientations - approved for horizontal, vertical, and overhead concrete and masonry anchoring, this expansion anchor adapts to diverse structural and mechanical fastening tasks on a single job site.
• Backed by rigorous independent testing - compliance with ACI355.2 and AC193 standards gives specifiers and inspectors a reliable paper trail, simplifying plan review and inspection sign-off on demanding structural projects.

Specifications

• Size: 1/4 in. x 3-1/4 in.
• MPN: STB2-25314F100
• Brand: Simpson Strong-Tie
• Diameter: 1/4 in.
• Length: 3-1/4 in.
• Thread Length: 2-7/16 in.
• Material: Carbon Steel
• Coating: Zinc Plated
• Finish: Zinc Plated
• Installation: Installs with 1/4 in. drill bit and 7/16 in. wrench size
• Packaging: Packs of 100 and Cartons of 500
• Drill Bit Diameter: 1/4 in.

Approved Applications

• Cracked and uncracked concrete applications
• Masonry applications
• Seismic design categories A through F
• High-wind structural anchoring
• Horizontal, vertical, and overhead installations

Frequently Asked Questions

What makes the Strong-Bolt 2 suitable for seismic conditions?

The Strong-Bolt 2 is qualified for static and seismic loading conditions covering seismic design categories A through F. Its dual undercutting embossments on each clip segment enable secondary expansion should a crack form and intersect the anchor location, significantly increasing the ability of the anchor to carry load if the hole expands.

What tools are needed to install this wedge anchor?

The Strong-Bolt 2 installs with a 1/4 in. drill bit and a 7/16 in. wrench size, making installation straightforward with standard tools.

What standards has the Strong-Bolt 2 been tested to?

The Strong-Bolt 2 has been tested per ACI355.2 and AC193, ensuring it meets rigorous performance standards for expansion anchors in concrete and masonry.

What material options are available for the Strong-Bolt 2?

The Strong-Bolt 2 is available in zinc-plated carbon steel, mechanically galvanized carbon steel, and Type 304 and Type 316 stainless steel, allowing selection based on environmental and project requirements.

Note: Product dimensions and/or thread length may differ from picture. Please see the item description above for specifications.