Case Study: Scanning a Parking Garage

understand what's underneath trademark trinity subsurface
Evan Mowbray

Case Study: Scanning a Parking Garage

Parking garages are everywhere now. They not only help keep cars out of the elements and bring an extra sense of security compared to street-side parking, but they also add parking to areas where expanding the lot out horizontally isn’t an option. Unlike your average roadside parking, they are however a complex structure, usually made up of concrete stacked upwards into the sky. Some of them get pretty tall too; one time a work site had its own parking garage and it took fifteen minutes by car to get to and from the top floor (mid-day parking was sparse). Because of a garage’s structural composition and wear, concrete might need to be repaired or rehabilitated in some areas. A crack may form that could require sawcutting in order to repair the issue. Sometimes, a structure may see a ton of use where multiple repairs need to be done before the entire structure gets to the point of needing a full replacement. How does our team at Trinity tackle these large concrete slab structures?

Let’s cover a small project first. Our team was called out to a job in Wilmington for a concrete scan over a crack at a residential parking garage. The project involved utilizing ground penetrating radar to ensure that the client didn’t hit reinforcement, rebar, or post-tension cables while making the repairs. Post-tension cables are especially dangerous if you cut through them without proper de-stressing equipment. They are tensioned to hold up large slabs of concrete, and breaking this tension can destroy entire portions of the structure as the kinetic energy releases. In the worst case scenarios, this could lead to a full structural collapse.  Despite this crack forming on the “first floor” of the actual parking area, there’s still the basement to account for and cables between the two floors. To find out what’s inside of a concrete slab, our team blocked out an area around the crack where the work would be performed. We used a ground penetrating radar scanner in order to get a signal through the slab without disturbing the concrete. This data allowed us to make marks of the area, put together a deliverable of the area and allowed for the repair team to understand where potential conflicts could arise and plan ahead.

Now let’s talk bigger. One of our larger projects over the summer was a multi-tier parking garage in Philadelphia. There were two options for the parking structure: you could either tear it down and build a new one, or you could rehabilitate the entire garage. Rehabilitation is the cheaper option, so we were called to scan the site. Because of the multiple floors and overall size of the parking garage, there were multiple Trinity technicians called out to the site over multiple days to complete the work. We used tools such as lifts to perform scans on the ceilings and columns, searching for any concealed utilities, structural features, and voids from under the concrete slab. We used a laser measuring tool to ensure we could line up clear marks on both the ceiling of the garage after scanning. We double-checked these lined up marks to ensure their correctness. We also used the Proseq 8100 to scan a larger area of the parking garage floor. To cover additional ground, we also performed a video pipe inspection of all of the PVC pipes running through the structure.

No matter how big or small your concrete structure is, Trinity Subsurface is your go-to team for scanning concrete for reinforcement, rebar, post-tension cables, voids and more. Visit our website to find out more about all of the services Trinity offers.

Back to Blog