The Simpson Strong-Bolt 2 5/8 in. x 8-1/2 in. Wedge Anchor is a wedge-type expansion anchor engineered by Simpson for high-performance structural connections in cracked and uncracked concrete and masonry. Dual undercutting embossments on each clip segment enable secondary expansion should a crack form and intersect the anchor location, significantly increasing load-carrying capacity when the hole expands - making this anchor an optimal choice for seismic and high-wind conditions. Finished in zinc-plated carbon steel, the Strong-Bolt 2 is tested per ACI355.2 and AC193 and qualified across the full range of seismic design categories, giving contractors and engineers a dependable, code-listed solution for critical anchoring applications.

Key Features

• Code listed for cracked and uncracked concrete, and masonry applications - gives engineers and inspectors the documentation they need for code-compliant installations without additional field testing.
• Dual undercutting embossments on each clip segment - enables secondary expansion if a crack intersects the anchor location, maintaining load-carrying capacity in compromised concrete.
• Qualified for static and seismic loading conditions (seismic design categories A through F) - covers the full code-recognized range, making this wedge anchor suitable for virtually any seismic zone or high-wind structural project.
• Chamfered top designed to prevent mushrooming during installation - protects the anchor head during driving for a clean, reliable set every time.
• Suitable for horizontal, vertical, and overhead applications - provides installation flexibility across a wide range of structural connection orientations without requiring a different anchor.
• Tested per ACI355.2 and AC193 - independently verified performance standards give specifiers and contractors confidence in published load values.
• Installs with a 5/8 in. drill bit and 15/16 in. wrench - straightforward tooling requirements keep installation efficient and minimize job-site setup.

Why This Product

• Built for the most demanding code environments - with qualification spanning seismic design categories A through F and testing per ACI355.2 and AC193, this expansion anchor meets the requirements of high-wind and seismic projects where performance documentation is non-negotiable.
• Secondary expansion technology protects load capacity in cracked concrete - unlike standard wedge anchors, the Strong-Bolt 2 uses dual undercutting embossments to maintain holding strength even after a crack forms and intersects the anchor, reducing the risk of connection failure in real-world conditions.
• Versatile across application types and orientations - code-listed performance in cracked concrete, uncracked concrete, and masonry, combined with suitability for horizontal, vertical, and overhead installations, means one anchor solution covers a broad range of structural fastening needs on a single job site.
• Zinc-plated carbon steel construction balances durability and cost - the zinc-plated finish provides corrosion resistance for a wide variety of interior and protected exterior applications, with mechanically galvanized and stainless steel versions available when the environment demands greater protection.

Specifications

• Size: 5/8 in. x 8-1/2 in.
• Manufacturer Part Number (MPN): STB2-62812F20
• Brand: Simpson Strong-Tie
• Diameter: 5/8 in.
• Length: 8-1/2 in.
• Thread Length: 4-15/16 in.
• Material: Carbon Steel
• Coating / Finish: Zinc Plated
• Installation: Installs with 5/8 in. drill bit and 15/16 in. wrench size
• Packaging: Packs of 20 and Cartons of 80
• Drill Bit Diameter: 5/8 in.

Approved Applications

• Cracked concrete
• Uncracked concrete
• Masonry applications
• Horizontal installations
• Vertical installations
• Overhead installations
• Seismic design categories A through F
• High-wind structural connections

Frequently Asked Questions

Is the Strong-Bolt 2 suitable for use in cracked concrete?

Yes. The Strong-Bolt 2 is code listed for both cracked and uncracked concrete, as well as masonry applications. Its dual undercutting embossments on each clip segment enable secondary expansion if a crack forms and intersects the anchor location, significantly increasing load-carrying capacity in that condition.

What seismic design categories is this anchor qualified for?

The Strong-Bolt 2 is qualified for static and seismic loading conditions covering seismic design categories A through F - the full range recognized under applicable building codes. It has been tested per ACI355.2 and AC193.

What tools are needed to install the STB2-62812F20?

Installation requires a 5/8 in. drill bit to bore the hole and a 15/16 in. wrench to tighten the anchor. The chamfered top is designed to prevent mushrooming during the driving process, helping ensure a clean and reliable installation.

Can this anchor be used in overhead or horizontal orientations?

Yes. The Strong-Bolt 2 is suitable for horizontal, vertical, and overhead applications, providing installation flexibility across a wide variety of structural and construction scenarios.

Note: Product dimensions and/or thread length may differ from picture. Please refer to the specifications listed above for accurate measurements.