How Are Concrete Bollards Secured to the Floor? Anchor Methods

Concrete bollards are secured to the floor by one of three methods: surface-mount with a steel baseplate and anchor bolts driven into existing concrete, fully embedded into a fresh-poured concrete footing, or post-tension cable-connected for K-rated configurations. Each method has a distinct anchor system, pull-out rating, and code path. Cojo retrofitted four cast-concrete decorative bollards at a Portland office complex in February 2026 using surface-mount baseplates with adhesive epoxy anchors -- the existing slab couldn't be excavated, but the slab was thick enough for proper anchor embedment. This guide breaks down all three methods.

For category context, see our What Are Bollards hub. For broader install reference, see How to Install Bollards. For pricing, see Concrete Bollard Cost.

What's the Surface-Mount Baseplate Method?

Surface-mount uses a steel baseplate welded or bolted to the bollard's bottom, with four to six anchor bolts securing the plate to existing concrete. This is the fastest install method and the one most commonly used for retrofit work.

What Anchor Bolt Sizes Work?

Standard surface-mount anchor specifications:

• 5/8-inch wedge anchors -- 4 to 6 inch embedment, 60 to 80 ft-lb torque
• 3/4-inch wedge anchors -- 5 to 7 inch embedment, 90 to 110 ft-lb torque
• 5/8-inch adhesive epoxy anchors -- 5 to 7 inch embedment, set with Hilti HY-200 or Simpson SET-XP
• 3/4-inch adhesive epoxy anchors -- 6 to 8 inch embedment

The U.S. Federal Highway Administration Roadside Hardware Pooled Fund Study has documented anchor pull-out testing for various wedge and adhesive systems. Adhesive anchors generally outperform wedge anchors in cracked concrete.

What Slab Thickness Does Surface-Mount Need?

Existing concrete must be at least 6 inches thick for proper 5/8-inch anchor embedment. For 3/4-inch anchors, 8 inches is the minimum. Anchors set deeper than 50% of slab thickness risk back-side spalling -- the concrete behind the anchor breaks out under load.

For thinner slabs, surface-mount is not the right method. Either a new poured footing or a core-drill retrofit becomes necessary.

How Does Embedded Installation Secure the Bollard?

Fully embedded installation places the bollard in a freshly poured concrete footing. The bollard is held by friction and chemical bond between the bollard surface and the concrete, plus the depth of embedment.

Embedment Depth and Diameter

For non-rated cast or concrete-filled steel pipe bollards:

• Standard: 24 to 36 inches deep, 12 to 18 inches across
• Loading dock or impact zone: 30 to 42 inches deep, 18 to 24 inches across
• K-rated: 48 to 60 inches deep per certified configuration

The American Concrete Institute ACI 318 Building Code governs minimum cover and bond development length for embedded steel.

How Does Concrete Bond Develop?

Concrete-to-steel bond develops over the cure period:

• 24 hours: roughly 30% of full bond
• 7 days: roughly 70% of full bond
• 28 days: full design bond

For cast-concrete bollards (where the bollard itself is concrete rather than steel pipe), the embedded section bonds to the surrounding footing as a single concrete monolith. This is the strongest connection method -- failure modes typically involve breaking through the surrounding concrete rather than the bollard pulling out.

What's the Post-Tension Cable Method?

Post-tension cable connection is used for K-rated bollard lines under ASTM F2656. The certification testing for many K-rated systems uses cables underground that connect adjacent bollards, distributing impact load across multiple posts.

How Does Cable Distribution Work?

When a vehicle strikes one bollard, the cable transmits load to adjacent bollards. The vehicle's kinetic energy is absorbed across the entire bollard line rather than concentrated at the strike point.

• Cable spec: Typically 3/4 to 1 inch diameter steel cable
• Cable depth: 36 to 48 inches below grade
• Tension: Per certified configuration, typically 5,000 to 25,000 lb pre-tension

This method is configuration-specific -- field modifications void the certification. The U.S. State Department SD-STD-02.01 crash-rating spec sheets reference cable-connected configurations as one path to K-rating.

When Is Cable Connection Required?

Cable connection is required when:

• The K-rated certification specifies it
• The site cannot accommodate the heavy individual foundations required for cable-free K-rated bollards
• Cost-per-bollard reduction matters more than per-bollard structural depth

Cable-connected K-rated systems typically use shallower individual foundations than cable-free systems, but the underground cable trench adds significant install labor.

What Code Compliance Issues Apply?

Three code references show up on most concrete bollard secure-to-floor projects:

1. IBC Section 1604 structural design. International Building Code adopted by Oregon mandates structural calculation for any bollard claiming impact resistance.
2. ADA Section 307 protruding objects. The U.S. Access Board ADA Standards require bollards to be detectable above 27-inch height and to avoid creating accessible-route conflicts.
3. Local seismic anchorage. Oregon's seismic design category requires anchorage calculation for any structural element. The Oregon Building Codes Division publishes the adopted versions of the IBC and IRC.

For the maintenance after install, see our bollard curb stop painting service guide. For Portland-area work where Cojo handles a lot of surface-mount retrofits, see Bollard Installation Portland.

What Are the Common Anchor Failures?

Three failure modes show up repeatedly in our retrofit work:

1. Pull-out under tension. Wedge anchors in cracked or thin concrete pull through the slab.
2. Concrete spalling at anchor. Anchors too close to slab edges (less than 4 inches) break out the concrete corner.
3. Adhesive cure failure. Epoxy anchors set in below-spec temperatures (under 40 degrees F substrate) fail to develop full bond.

Each failure traces back to choosing the wrong method for the slab condition. A site survey with a rebar locator, slab-thickness measurement, and crack inspection prevents most failures.

How Do You Choose Between Methods?

The decision tree:

• Existing concrete 6+ inches thick, no major cracking, no excavation possible: Surface-mount with adhesive epoxy anchors.
• New construction or excavation possible, non-rated bollard: Embedded with new pour.
• Existing concrete, cannot break it up, non-rated bollard: Core-drill retrofit (covered separately in How to Install Bollards in Existing Concrete).
• K-rated requirement: Per certified configuration -- almost always embedded with engineered foundation, sometimes cable-connected.
• Cast-concrete monolithic bollard, new pour: Embedded as single concrete pour for maximum strength.

Get a Site-Specific Anchor Plan

Concrete bollard anchor systems are not one-size-fits-all. Slab thickness, existing reinforcement, expected impact, and code requirements all interact. Cojo specs and installs concrete bollards across Oregon using all three secure-to-floor methods, including engineered drawings for K-rated work. Contact Cojo for a site-specific anchor plan.