The Simpson Strong-Bolt 2 1/2 in. x 8 1/2 in. Wedge Anchor is a wedge-type expansion anchor engineered for high-performance anchoring in both cracked and uncracked concrete. Built from zinc-plated carbon steel, this anchor is designed to maintain reliable load-carrying capacity even under demanding seismic and high-wind conditions - making it a dependable choice for structural anchoring in concrete where performance cannot be compromised. Dual undercutting embossments on each clip segment enable secondary expansion should a crack form and intersect the anchor location, significantly increasing the anchor's ability to carry load if the hole expands.

Key Features

• Chamfered top designed to prevent mushrooming during installation - keeps the anchor thread intact and reduces installation errors, helping ensure a secure, properly seated connection every time.
• Dual undercutting embossments on each clip segment enable secondary expansion - provides a critical safety margin if a crack intersects the anchor location, maintaining load-carrying performance in compromised concrete.
• Qualified for static and seismic loading conditions (seismic design categories A through F) - gives contractors and engineers the code confidence needed for structural applications in high-risk seismic zones.
• Suitable for horizontal, vertical, and overhead applications - offers installation flexibility across a wide range of field orientations without requiring a different anchor for each scenario.
• Tested per ACI355.2 and AC193 - independently verified performance standards confirm suitability for use in cracked and uncracked concrete, supporting engineering approvals and inspections.
• Made from zinc-plated carbon steel - provides a corrosion-resistant finish appropriate for standard interior and protected concrete anchoring applications.
• Installs with a 1/2 in. drill bit and 3/4 in. wrench size - straightforward tooling requirements mean faster setup and compatibility with standard jobsite equipment.

Why This Product

• Built for seismic and high-wind environments - the Strong-Bolt 2 is qualified across seismic design categories A through F, making it one of the few wedge anchors suited for the most demanding structural code requirements without substitution or special engineering.
• Secondary expansion technology protects performance in cracked concrete - the dual undercutting embossments engage if cracking occurs at the anchor point, allowing the fastener to continue carrying load rather than losing capacity when the concrete moves.
• Versatile orientation support simplifies project planning - approved for horizontal, vertical, and overhead concrete anchoring, this single anchor solution reduces the need to source multiple products for different installation angles on the same jobsite.
• Third-party tested to recognized industry standards - compliance with ACI355.2 and AC193 provides engineers, inspectors, and contractors with documented proof of performance, streamlining approval processes on regulated construction projects.

Specifications

• Size: 1/2 in. x 8-1/2 in.
• MPN: STB2-50812F20
• Brand: Simpson Strong-Tie
• Diameter: 1/2 in.
• Length: 8-1/2 in.
• Thread Length: 6 in.
• Material: Carbon Steel
• Coating/Finish: Zinc Plated
• Install With: 1/2 in. drill bit and 3/4 in. wrench size
• Packaging: Packs of 20 and Cartons of 100
• Drill Bit Diameter: 1/2 in.

Approved Applications

• Cracked and uncracked concrete anchoring
• Seismic design categories A through F
• High-wind structural conditions
• Horizontal, vertical, and overhead installations
• Static and seismic loading conditions

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 across 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, which significantly increases its ability to carry load if the hole expands - a critical advantage in seismic and high-wind environments.

What tools are needed to install this wedge anchor?

The Simpson Strong-Bolt 2 installs with a 1/2 in. drill bit and a 3/4 in. wrench size, making it straightforward to install in field and construction applications.

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

The Strong-Bolt 2 has been tested per ACI355.2 and AC193, confirming its performance compliance for use in cracked and uncracked concrete applications.

Can this anchor be used in overhead or horizontal installations?

Yes. The Strong-Bolt 2 is suitable for horizontal, vertical, and overhead applications. The chamfered top is specifically designed to prevent mushrooming during installation, ensuring reliable performance across all orientations.

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