Escambia County, Solid Waste Transfer Stations
Tipping Floor Repair, Re-topping, and Protection
Epoxy barrier lining with Epoxytec 17G
Certified Applicator: Cypress Construction & Coatings, Inc.
Municipal solid waste transfer stations across the world have one thing in common, their tipping floors experience some of the worst corrosion in existence; a combination of ultra-high abrasion and wear coupled with deteriorating chemical attack due to leachate and microbial induced acid, not to mention the assortment of unidentified contaminants to boot. This of course was not different for Escambia County, Florida.
At the transfer station, garbage trucks cycle and constantly dump (tip) mounds of waste onto bare concrete floors, where bulldozer blades push the refuse into bunkers for extraction.
During the process, corrosives saturate the concrete leaving it etched and weakened, while the blades follow through and expedite the wear to the already weakened concrete.
To solve this, solid waste facilities consult with Epoxytec, a leader in tipping flooring system solutions for ultra-high performance repair and rehabilitation.
Epoxytec is the manufacturer of the 17G system, a customized epoxy barrier slab for combating ultra-high wear and abrasion, while sealing and protecting the concrete as a liner against ponding leachate/water and therefore protecting the environment.
The video below demonstrates the typical process of the rehabilitation system:
for more videos, visit Epoxytec TV
The Epoxytec 17G system was selected as a sectional system for this project to be installed on half the floor in 2010, and the other half later in the near future. For this blog, the first half is documented.
To successfully apply the system as a sectional liner, an undercut was created into the existing slab to provide a flush transitional point of termination, so the that the dozer blades do not chip a high exposed edge, but rather make a flush approach.
After creating the key way, undercut, the floor then needed to be prepared. The Epoxytec certified contractor utilized an Ultra-High Pressure Water Jetting rig to blast. The UHP equipment not only blasts and etches concrete, but also rids all contaminants with 40,000psi of water, enough to cut granite.
The UHP method is practical and effective, as it cleans and blasts all-in-one-shot. Attached is an optional “floor hog” add-on for blasting while overspray is being contained in a vacuum environment, therefore debris doesn’t effect the surrounding crew or equipment.
The picture below demonstrates the awesome nature of the blast, leaving a noticeable, clean and etched surface, ridding all loose concrete and removing all contaminants by deep and high pressure extraction. Doing this provides a surface to NACE Surface Preparation standards, SSPC-SP13/NACE No.6.
After blasting, the crew worked throughout the evening and rinsed with ultra-high temperature, high pressure water blasting to further rinse and clean via deep penetrating steam.
After the surface prep was completed, the rinse exposed a medley of cracks throughout the floor surface. To navigate through this setback, the experienced crew knew they needed to level these cracks before applying the 17G system. Using the resin-mix of the 17G with a small ratio of aggregate filler, provided a consistent slurry mix to fill the cracks in before application.
The cracks appeared in all sizes.
Being the the cracks were caused from unknown reasons, the system had to address the potential of movement. Therefore, the crew decided to utilize fiber-mesh within the slurry filler to combat and bridge any unforeseen movement that may occur in the future.
Using fiber-rolls, the material was laid on top of the 17G resin filler and crack.
After which, the 17G resin was applied to embed the fiberglass.
Before applying the system, priming was specified to assist in any out-gassing or and water vapor transmission (MVT) that may occur. Using the Epoxytec B2 Primer, a water-based epoxy primer, ensures the proper sealing of moisture and out-gassing before application of the epoxy 17G system.
The entire surface of the tipping floor to be lined by 17G is coated first with the B2 Primer. This waterborne primer has no VOCs, indicates top coating readiness when it turns clear, and penetrates deep into the concrete surface crosslinking with the existing moisture, as it is itself, water-based. Once cured, the B2 Primer provides a the chemically sealed adhesive enhancement with a glossy finish to facilitate the application and glide for the top liner.
Once the primer is initially cures, the application of Epoxytec 17G can begin. The 17G is a highly filled, 3 component, trowel-grade epoxy liner, and when applied and cured provides anti-abrasive wear resistance with incredible compressive properties of 17,800psi. The highly dense material cured to a heavy, epoxy slab like top liner which also provides chemical resistance and sealed barrier lining.
To get started with 17G, mixing logistics must first be organized and decided upon. Typically, the material can be mixed in a pre-proportioned kit with a power drill. However, for large job, a mortar mixer provided a more efficient method of mixing in volume.
Once mixed in volume, the material was transported with a simple hand cart and then poured onto the surface. The material needed to float, ultra-high build at a least 1/4″ – 3/8″. Some floors, depending on the profile may even require more, such as 1/2″ – 1 inch. For this project, the 17G was applied between 3/8″ – 1/2″ in some areas.
Utilizing a pour-and-spread method, certain tools benefited the application crew well. These tools included an assortment of trowels and pin rakes. The 17G material, although trowel-grade, has an ability to blend in well, as the top surface does settle a bit to help alleviate minor inconsistencies.
The project was completed in 3 days, and was returned to service after 24 hrs. The total square footage was circa 5,500 sq.ft.