Pasarelle Beilly Waterproofing, Paris
The Beilly footbridge in Paris, 300 square metres of concrete, was waterproofed with hot-sprayed Impermax Polyurea H Flex. A quartz-filled Porosity Sealer Flex coat protects that film from the hot asphalt and from the machines that lay it.
Overview
The Beilly footbridge in Paris, 300 square metres of concrete, was waterproofed with hot-sprayed Impermax Polyurea H Flex. A quartz-filled Porosity Sealer Flex coat protects that film from the hot asphalt and from the machines that lay it.
| Place | Pasarelle Beilly, Paris, France |
|---|---|
| Area | 300 square metres |
| Substrate | Concrete |
| Membrane | Impermax Polyurea H Flex, hot spray, about 2 kg per square metre |
| Protection | Porosity Sealer Flex with quartz, then asphalt |
Challenge
A footbridge deck is a thin concrete slab with movement at the bearings and water that cannot pond. Three hundred square metres is small, which makes the details a larger share of the job. Cracks in a bridge deck pump water every time a load crosses.
The membrane has to be under the asphalt, complete, and bonded. If it is thin at a crack, the asphalt hides the leak until the soffit shows it. The asphalt itself arrives hot, about 160 degrees C, and the paver drives on whatever is under it.
Solution
Impermax Polyurea H Flex is a hot-spray polyurea membrane from Krypton Chemical. On this bridge it is the waterproofing. Asphalt is only the coat people walk or drive on. Between them sits Porosity Sealer Flex, broadcast with quartz, so the hot mix and the machines meet a protective coat and not the waterproofing film.
Elongation at break is about 400 percent and tensile strength about 15 MPa, with Shore hardness about 90A / 40D. Those are typical product data, not a core from this deck. The product carries ETA 21/0740 for waterproofing of bridge decks. The spray locks as it lands, so the deck can take the next coats on a film that is already a film, not a wet roller coat.
Application
The concrete was treated with a diamond grinding machine. Cracks were repaired and filled with Rayston Flex. Primer went onto concrete that was dry, cured, clean of dust, oils and silicones, and cohesive. Rayston Epoxy 100 was applied at about 0.45 kg per square metre. Quartz sand was broadcast over the primer before it cured. The primer’s job is to close the pores and give the spray a bond.
Impermax Polyurea H Flex was then hot-sprayed across the 300 square metres at about 2 kg per square metre. Porosity Sealer Flex followed at about 0.25 kg per square metre and was broadcast with quartz, 0.4 to 0.8 mm, to saturation. That coat is what meets the asphalt at about 160 degrees C and what the laying machines drive on. Grinding dust left in a crack is a bond breaker, so the vacuum and the mastic are part of the waterproofing.
Results
Pasarelle Beilly has a hot-sprayed Impermax Polyurea H Flex membrane under asphalt. The concrete was opened by grinding, the cracks were filled with Rayston Flex, Epoxy 100 primer sealed the deck at about 0.45 kg per square metre, and Porosity Sealer Flex with quartz stands between the membrane and the hot asphalt.
Products
Impermax Polyurea H Flex
Hot-spray membrane on the bridge deck, about 2 kg per square metre, under the protective coat and the asphalt. Elongation about 400 percent. Product data.
Porosity Sealer Flex
About 0.25 kg per square metre, broadcast with 0.4 to 0.8 mm quartz, to protect the membrane from asphalt at about 160 degrees C and from the paving machines.
Rayston Flex and Rayston Epoxy 100
Rayston Flex filled the cracks after grinding. Epoxy 100 primed the concrete at about 0.45 kg per square metre, with quartz broadcast into the wet primer.
FAQ
What membrane is on the bridge?
Impermax Polyurea H Flex, hot-sprayed at about 2 kg per square metre onto primed concrete. The deck is 300 square metres at Pasarelle Beilly, Paris. Asphalt is the wearing course. It is not the waterproofing.
How was the concrete prepared?
The deck was diamond-ground. Cracks were filled with Rayston Flex, a single-component polyurethane mastic. Rayston Epoxy 100 primer then went on at about 0.45 kg per square metre, and quartz was broadcast into the primer while it was still wet.
Why is there a coat between the polyurea and the asphalt?
Asphalt goes down at about 160 degrees C, and the machines that lay it are heavy. Porosity Sealer Flex, about 0.25 kg per square metre, broadcast with 0.4 to 0.8 mm quartz, is there to take that heat and that traffic so the waterproofing film is not the surface the paver drives on.
What do the strength figures mean on this deck?
Impermax Polyurea H Flex has an elongation at break of about 400 percent, a tensile strength of about 15 MPa, and a Shore hardness of about 90A / 40D. Those are typical product data, not a core cut from Pasarelle Beilly. The product carries ETA 21/0740 for waterproofing of bridge decks.
What does the spray need?
A two-component hot-spray machine, a dry and cohesive deck, and a primer that has sealed the concrete. Wind and an incomplete prime show up as texture and pinholes. On a 300 square metre bridge the details are a large share of the area, so the grinding and the mastic are part of the waterproofing.