How The Dwyer Company Supported a New Building Addition Over 14 Feet of Fill at O’Rourke Wrecking Company
- Project Type: Commercial
- Project Services: Deep Foundation Systems, Helical Piles
O’Rourke Wrecking Company added onto its building in Cincinnati, Ohio, on a site carrying 12.5 to 14 feet of existing fill soils. The Dwyer Company installed 51 helical piers to support the addition, working with general contractor Terrex Development & Construction and engineer Civil Solutions. Each pier was designed for 20 to 30 kips in compression, 1 kip uplift, and 2 to 4 kips lateral, with depths running between 10 and 21 feet. The piers carried the addition below fill that ruled out conventional footings.
Building on a site full of existing fill?
Quick Facts
- Cincinnati, Ohio
- Project Type: Commercial – New Construction
- Owner: O’Rourke Wrecking Company
- Foundation System: 51 new construction helical piers supporting the building addition
- Pier Capacity: 20 to 30 kips in compression, 1 kip uplift, 2 to 4 kips lateral
- Pier Depth: 10 to 21 feet
- Soil Conditions: 12.5 to 14 feet of existing fill soils
- Site Conditions: Tight site with utilities throughout the work area
- Partners: Terrex Development & Construction (general contractor), Civil Solutions (engineer)
The Challenge
The site carried 12.5 to 14 feet of existing fill. Fill at that depth cannot be counted on to carry a footing, because what went into it and how it was compacted are rarely known well enough to design against. Conventional footings were out, so the addition needed a system that reached below the fill to material that could take the load.
The site was tight and crowded with utilities on top of that. Lines ran through the work area, and 51 pier locations meant 51 places where a crew could find one. Tracking what was buried shaped how each location was laid out and worked.
Key Project Details
new construction helical piers installed for the building addition
The Solution: Helical Pier Foundation System
The Dwyer Company installed 51 helical piers to carry the addition below the existing fill. Each pier was designed for 20 to 30 kips in compression, 1 kip uplift, and 2 to 4 kips lateral. Depths run between 10 and 21 feet across the layout, since each pier advances until it meets its design capacity instead of stopping at a fixed elevation.
Utilities set the working conditions. Lines ran through a tight site, so the crew tracked what was buried at every pier location and installed around it. Coordination with Terrex Development & Construction and Civil Solutions kept 51 piers moving on a footprint with little room to spare.
The Impact
Fifty-one piers put a building addition on competent bearing below 14 feet of fill.
Bearing below the fill
Each pier advanced past the existing fill soils to material that could carry the addition.
Capacity beyond gravity load
Piers were designed for uplift and lateral load along with 20 to 30 kips in compression.
Utilities left intact
Attention to buried lines at every one of the 51 locations kept the existing utilities undisturbed.
Built on a tight footprint
Compact equipment installed the full pier layout on a site with limited working room.
Why Helical Piers?
Helical piers let The Dwyer Company put an addition on competent bearing under 14 feet of fill, on a site where digging that fill out was impractical.
- Bypasses existing fill – Piers advance past uncontrolled material and land in the soil below it.
- Adapts to changing depth – Each pier advances to capacity, so depths follow the conditions across a site.
- Capacity in more than one direction – A single pier can be designed for uplift and lateral load along with compression.
- Small equipment footprint – Compact machines work tight sites and install around buried lines.
Why Choose The Dwyer Company for structural integrity?
Deep History • Solid Choice
The Dwyer Company’s proven track record in commercial and industrial foundation systems made us the trusted partner for the O’Rourke Wrecking Company building addition. Working alongside Terrex Development & Construction and Civil Solutions, our crew installed 51 helical piers through 14 feet of fill on a tight site and gave the addition the bearing its design required.
Have an addition planned on fill or a crowded site?