By Lynn Connors, GCP Applied Technologies
Skanska USA, the contractor hired to construct the $400 million Pensacola Bay Bridge, could earn a $15 million bonus for completing the work early. Likewise, when it contracted out the development of a collapsed section of Interstate 85, the Georgia Department of Transportation offered a $3.1 million early completion bonus to the contractor.
Fast-tracking bridge projects can be very lucrative for contractors – if the work is done right. There are numerous steps along the way where work can be accelerated. One of these is when waterproofing the bridge deck.
Choose the Right Removal Method
If you’re refurbishing a bridge, removal of original coating and waterproofing can be a time-consuming process. Talk with your waterproofing manufacturer to find out about the various removal methods, such as water blasting, that could minimize manual efforts. The removal method will depend on many factors, including the chemical composition of the original coatings and the type of waterproofing membrane now being applied.
Involve the Manufacturer and Applicator in Pre-site Inspections
This is important for new construction as well as refurbishment projects. For bridges that are being refurbished, the condition of the existing paving and waterproofing membrane will influence the refurb plan. For example, the amount of surface prep needed can vary, depending on the type and condition of materials used previously. In some cases, a single pass of a blast machine won’t be enough to clean the surface. If this prep isn’t done right, it can impact the bond between the bridge waterproofing and the substrate.
It can be hard to know what situation you’re getting into without seeing these conditions firsthand, which is why pre-site visits are essential.
Prevent weather delays
As the weather gets colder, ice crystals or condensation may accumulate on the bridge deck. This can result in work being halted when it’s too cold out. Nobody wants to have a crew waiting around to apply waterproofing until the weather changes. To extend your construction season and avoid work delays, choose a liquid waterproofing system that can be applied in moist, freezing temperatures.
Use On-the-Spot QA Tools
Having the right QA methodologies give contractors the peace of mind that they’ve performed a high-quality application. It’s easy to validate the waterproofing membrane’s performance through adhesion testing that ensures the entire system is going to be fully bonded to the substrate. This way as you apply subsequent coats of waterproofing, you know you have a chemical bond between the waterproofing layers and the substrate below. Wet film-thickness testing can also be performed immediately to verify the waterproofing was applied properly. This allows applicators to instantly identify and repair any areas in need.
In addition, products like the ELIMINATOR waterproofing membrane have a color-coded system that enables applicators to confirm full spray coverage at a glance. Overcoating can be performed at any time, offering greater flexibility and high-performance adhesion at day joints.
Consider a Phased Approach
Having the flexibility to perform certain work, such as spraying on waterproofing, during overnight possession can accelerate project completion and minimize frustration for the commuters who rely on the bridge. This is a factor to consider when selecting your waterproofing membrane. For example, by broadcasting aggregate at 100 percent “to refusal” onto the membrane, the ELIMINATOR waterproofing membrane can temporarily be trafficked by vehicles within one hour of application. This gives you the flexibility to apply waterproofing at night, open the bridge to traffic in the morning and then apply asphalt paving the next night.
Confirm That the Membrane can be Applied Cold Anytime
Many waterproofing membrane manufacturers claim to have liquid membranes that are cold applied. However, some of these products must be heated up when used in the wintertime so they don’t become too thick. To avoid this extra step, and the extra cost of bringing generators to the site, it’s best to choose a product that can be applied cold anytime of the year.
Lynn Connors is Global Marketing Manager of Liquid Applied Waterproofing at GCP Applied Technologies. Connors has over 15 years’ experience growing emerging markets by bringing innovative solutions to market. She has held senior management positions at iRobot Corporation and Velcro USA Inc. Connors has an Executive MBA from the University of New Hampshire.