CNC Foundations, Inc.

Scope Of Work

Product Type: Aggregate Piers/VSCs

The existing fill on the jobsite consisted of loose silt, sand, clay, and gravel. It could not successfully sustain the weight of the proposed structure. Without intervention, it ran the risk of significant future settlement.

Settlement, to some degree, is a natural part of a building’s life cycle within the first few years following construction. Excessive settling can become an issue that weakens the foundation, causing cracks, and impacting building services like plumbing.

One of the leading causes of significant settlement is a weak bearing soil like the conditions that were present for the Multi-Family Residences Project. Issues with settlement can be resolved later in the life of a building, but it is always best to be proactive about these issues

What Did We Install?

We installed vibratory stone columns (VSC). The proposed depth was up to 30 feet, but worked out to an average of about 21 feet being needed once we were in the field. CNC Foundation can adapt to changes in the field like this thanks to our years of experience and our extensive library of products and materials.

Based on the field reports of the topsoil in the borrow pit, we assessed that the VSC would be acceptable and work well within the project parameters. There was about 350 LF of strip footings and a few column pads, so vibratory stone columns were recommended.

Were There Project Challenges?

The exact depth and characteristics of the soil were still in question before we arrived. From the information we were given, we expected the topsoil to be about 15- to 20 feet below BOF. For the sake of the early submittals, we were forced to make a conservative estimate of 30 feet to sign off on the design.

The general contractor is a large national firm with a comprehensive contract process. It was decided we would be second-tier sub to the excavator on this particular project. We have ample experience working with others on the worksite, and we always bring a spirit of teamwork to every work environment. The owner of the excavating company was an excellent advocate to work with throughout the process. He referred the work to us and was there to help negotiate the final pricing.

The most substantial challenge of the project was making sure our equipment and the footings were not damaged. The existing adjacent footings were already poured, so we needed to perform the installation very close to the existing footings. Our experience in the industry and knowledge of the equipment served us well in maintaining the condition of both the equipment and footings.

What Was the Result of the Project?

Overall, the project went very well. Early on, we were able to expedite the entire process for the customer and general contractor. Under a tight timeline, we managed the contract, submittals, mobilization, and installation with professional workmanship. The general contractor was pleased with our work.

One of the reasons we’ve become the popular choice for so many contractors is thanks to our wide range of specialties and our capabilities in those fields. We offer in-house services such as project management, engineering and load testing, preliminary geotechnical design, and design/build construction. To learn more about CNC Foundations, our capabilities, and everything we have to offer, contact us by filling out the form below.