The vital role that waterproofing plays in public transport networks cannot be underestimated, where an effective waterproofing membrane will prevent expensive damage and disruption.
At the new multi-billion dollar Doha Metro system in Qatar’s capital city, more than 1,000,000m2 of Grace Construction Products’ Preprufe Plus is being installed to provide long term protection against ground water, an average annual temperature of 32°C and chloride and sulphate attack.
Set to become one of the world’s most advanced rail transit systems, the Doha Metro will consist of four lines – blue, red, green and gold – and approximately 100 stations when complete. To be built in two phases, Phase 1 includes the construction of two major stations at Msheireb and Education City and 30 other stations by 2019, with the second phase delivering over 50 stations by 2026.
Contractors on the scheme required a reliable and high quality waterproofing system that would keep the stations ‘completely dry’, and with a 120-year design life. For Phase 1 of the project, four of the five main contractors specified Preprufe Plus for use predominantly below the bases of more than 30 stations and cast onto diaphragm walls in a number of additional locations.
“We chose the Grace products based on two main factors,” explains Constantinos Demetriades, Project Director for Aktor, the company leading a Joint Venture to deliver the metro’s Gold Line. “First reliability and knowing the products, and second, ease of use."
Preprufe is an advanced membrane system which offered the safest and most reliable waterproofing option. Designed with synthetic adhesive layers, Grace’s patented Advanced Bond Technology enables concrete to aggressively adhere to Preprufe, forming a unique intimate seal which prevents any water migration between the waterproofing and the structure, substantially reducing the risk of leaks.
No other system on the market protects a substructure from the harmful effects of water, vapour and gas better than Preprufe. It can also be applied on wet concrete and is immediately trafficable after installation, which makes for fast and easy installation. To complete the comprehensive waterproofing specification, Grace also supplied its Bituthene® 8000HC preformed membrane to provide a continuous waterproofing barrier system where the outside of the walls can be accessed.
“We have been manufacturing Preprufe for 21 years, mainly for basement construction,” says Grace’s global projects manager Rob Hossell. “We have had a lot of success in the Middle East where there are lots of basements and high water tables. And in the last few years, we have moved more and more into infrastructure.”
The success of landmark transport projects which have used Preprufe® perfectly demonstrates the importance of specifying a geomembrane which is fit for purpose, economically and environmentally sustainable and delivers waterproofing performance like no other system on the market. Proven to deliver in the most challenging environments, Preprufe continues to be chosen to protect many of the most important infrastructure projects worldwide.