PROJECT STATS: 

  • Concrete yardage: 3,300 cubic yards 
  • Rebar: 250 tons 
  • Man hours: 50,000 
  • Excavation work: 800 tons of rock 
  • Contractor: TW Frierson  

All concrete work requires precision, but when working in an active industrial facility, the stakes are even higher. At the Nissan plant outside of Nashville, we were tasked with excavating and pouring press pits—specialized machine foundations designed to support the weight, force, and vibration of industrial press equipment.

This project involved two distinct press pits: the Trial Pit and the XL Pit. Each required meticulous planning, precise execution, and creative problem-solving to minimize disruption to the plant’s daily operations. Ensuring a level floor was critical, with specifications demanding tolerances as tight as 1/8th of an inch.

Chad Johnson, the project manager for this job, shares an inside look at some of the key challenges and solutions that Superintendent Mario Galindo and the field team overcame to make this project a success.

Demolition and Concrete Pours at a Massive Scale

The excavation of the Trial Pit was no small task. The last 15 feet of the demolition involved solid bedrock, and due to the location being inside an operating facility, traditional blasting wasn’t an option. Instead, we had to hammer through roughly 18,000 cubic feet of rock. To ensure a clean excavation, we used a specialized John Henry Rock Drill to create a precise, sheer boundary around the edges before removing the rest of the material. 

The final pit dimensions measured 40 feet long, 30 feet wide, and 25 feet deep. At the bottom, we poured a 2.5-foot-thick concrete slab with walls that were two feet thick. This foundation also included four massive piers, each requiring nearly 60 cubic yards of concrete to support the press. Since we were working below the water table, we used a water-repellent concrete mix to prevent water from seeping into the foundation. This choice of material will also help maintain structural integrity over time.

A Cautious and Meticulous Approach

The XL Pit presented a different challenge. Unlike the Trial Pit, this area was already a pit, but it needed to be significantly expanded. This made the work more complex, as we had to carefully navigate existing infrastructure. The XL Pit was three to four times larger than the Trial Pit and required 12 concrete piers to properly support the press.

“We were incredibly intentional about our formwork, making sure everything tied seamlessly into the existing concrete,” Johnson explained.

Working within an active plant meant we had to be extremely careful with existing tubing and conduits. Damaging any of these could have disrupted operations across the entire facility. To prevent this, we set up dust partitions and ran air scrubbers to minimize exhaust from our heavy machinery, ensuring a safe and functional workspace for everyone.

One of the biggest challenges was keeping dust levels down while maintaining progress. To further control dust, we constantly sprayed water, which was then pumped out from the bottom of the pit. This approach kept the work site and surrounding plant operations clean and functional.

A key step in finishing the pit was applying a dry shake floor hardener to the surface. This was crucial for strengthening the top layer to withstand the intense traffic and pressure the press would exert. Applying this hardener required a meticulous process—initially done by hand—to ensure even distribution across the pit.

“We had to carefully calculate the exact amount needed to ensure a uniform and durable surface,” Johnson explained.

Delivering Precision and Innovation

Despite the challenges, our team delivered a high-precision foundation that met Nissan’s strict specifications while minimizing operational disruptions.

“I’m really proud of what the field team was able to accomplish—from finding creative ways to keep the plant running smoothly to meeting incredibly tight tolerances for a press of this size and magnitude,” Johnson said.

At Charter, we thrive on complex industrial projects like this one, bringing expertise, precision, and problem-solving to every job we take on.