Precision Concrete Stabilization and Joint Sealing in Waterloo, IA
Challenge
A residential driveway in Waterloo, IA, presented with significant differential settlement between adjacent concrete slabs. System Design Specialist Shawn Conaway conducted a site evaluation and determined that the primary cause of the displacement was the erosion and compaction of the underlying Iowa subgrade. The resulting vertical offsets (lips) exceeded 1.5 inches in several areas, creating high-risk trip hazards and compromising the structural integrity of the driveway.
The homeowner’s priority was a non-invasive solution that provided immediate load-bearing capabilities. Traditional mudjacking was ruled out due to the excessive weight of the slurry, which can often cause secondary settlement in weak Iowa soils. Shawn designed a plan utilizing high-density polyurethane injection to address the voids without adding significant overburden to the soil.
Solution
Foreman Ricky Sigala and his production crew executed the stabilization process using the following technical steps:
- Access Points: The team drilled a series of 5/8-inch "penny-sized" injection ports strategically across the subsided slabs.
- Polymer Injection: High-density PolyLevel® foam was injected through these ports. As the two-part polymer expanded, it filled the subsurface voids and exerted precise upward pressure on the slabs.
- Controlled Lift: Using constant monitoring, Ricky achieved a precise lift, bringing the slabs back to their original grade and eliminating the tripping hazards.
- Rapid Cure: Unlike concrete or mudjacking, the PolyLevel® reached 90% of its compressive strength within 15 minutes, allowing for immediate foot and vehicle traffic.
To ensure the longevity of the lift, the team addressed the "root cause" of the erosion—water infiltration.
- Joint Preparation: Existing cracks and expansion joints were cleaned of debris and old, failing filler.
- Application: NexusPro® silicone-based sealant was applied to provide a UV-resistant, waterproof barrier. This prevents future "washouts" of the subgrade and protects the slabs against the harsh freeze-thaw cycles typical of the region.
The project resulted in a fully stabilized, level driveway with a clean, aesthetic finish. By utilizing a lightweight, high-strength polymer, Shawn and Ricky provided a permanent solution that bypassed the mess of demolition while ensuring a safe, "sashay-ready" surface for the homeowner.
