Preventative Soil Stabilization for Retail Upfit Project in Charlotte, NC

The Challenge

Stopping potential future settlement.

During the upfit of an existing commercial building into a new retail location in Charlotte, North Carolina, an engineering firm identified a potential for future settlement beneath the structure’s spread footings. Soil borings revealed that the planned upfit would add significant new loads to 11 steel support columns—more than what the existing spread footings were originally designed to bear. This increase in expected weight raised concerns about up to ¼ inch of potential settlement over five years. Rather than installing helical piers, the property owner opted for a less invasive and cost-effective soil stabilization approach to prevent future issues.

Key Facts

The Solution

Post-design reinforcement with polyurethane.

Groundworks was contracted to reinforce the soil beneath the identified spread footings using deep geotechnical polyurethane injection. Injections were performed at two depths—10 feet and 5 feet—beneath each of the 11 steel columns. This bottom-up injection strategy ensured proper soil densification and structural support for the additional weight being introduced by the upfit design. The intervention served as a form of post-design reinforcement, stabilizing the area ahead of any observable damage or settlement.

The Impact

Prevention of future settlement and costly underpinning.

The proactive soil stabilization helped avoid costly and disruptive underpinning methods while ensuring the structure could safely accommodate increased loads. The injection process was performed without excavation and with minimal interruption to the renovation schedule. By addressing potential settlement before it occurred, the project protected the integrity of the upgraded structure and provided long-term peace of mind for the stakeholders involved.