Structural Repair on a Two-Story Building Due to Flooding

Christina Tenaglia found herself in an unexpected situation when a pipe in the building next door burst. Major flooding affected her property, resulting in three feet of water in her basement. Structural issues began when the existing 18”x18” concrete piers started sinking 1 to 1 ½ inches. They began to twist and buckle, causing foundation instability in the building. Additionally, commercial and residential tenants were living in the building while this repair had to be mitigated and fixed. Limited access to the basement and the confined space created even more challenges in this situation.

Year: January 2017

Dealer: Techno Metal Post Hudson Valley

Engineer in charge of the project: Geotechnical and Structural Engineers on site

Location: Beacon, New York, USA

Main contractor: Lambert & Grenier

Project objectives: Restore and support the existing structure of the two-story building

Specific challenges:

• There was only a 28” existing opening to access the basement, so getting machinery into the building posed a huge challenge.
  Solution: Techno Metal Post’s proprietary R2D installation equipment was modified to access the basement. The outside wheels were removed to reduce the size of the installation equipment, and a special ramp and landing were built to lower and raise the R2D in and out of the basement.
• Commercial and residential tenants still needed access to their units while the foundation repair was underway.
  Solution: All work at the end of the day had to be thoroughly cleaned up and ready for tenants to enter the property.
• Confined spaces presented challenges for using equipment with flammable ignition sources like gas or diesel.
  Solution: Use the electric hydraulic motor for the R2D to avoid gas emissions during equipment operation. Any welding had to be properly exhausted out of the building.

One of the key advantages of using helical piers for this building's repair and restoration was their ability to reach the necessary depth, accessing the shale rock without disturbing the surrounding ground. Excavating the concrete piers would have caused them to sink further, resulting in an unrepairable building. Techno Metal Post's R2D installation equipment became the only solution that could be used to access the basement, thanks to its small size.

Materials used:

• P3 helical piers
• Welded 5-foot extensions
• Adjustable brackets

Type of soil: Up to 7 feet was sandy clay, and at 7 feet, solid shale rock

Equipment used: R2D Electric Hydraulic Motor

Bearing Capacity: 20,000 lbs

Insertion depth: Approximately 9 feet

Structural details: A two-story residential/commercial building housing three residential tenants and one commercial renter. A 3-foot flood began sinking the building by 1 to 1 ½ inches, so underpinning brackets were used and helical piers were installed to lift and support the building. As a result, the foundation regained its original height and became structurally sound.