Construction projects in the United Arab Emirates (UAE) face many challenges due to the harsh environment of the Gulf region. Hot weather, high humidity, and high concentrations of corrosive salts in many building locations and materials create difficulties for construction. High temperatures are a particular concern because fresh concrete gives off heat while it is hardening and any added heat greatly increases the chances of crack formation. The current practice in the region is to add ice to the concrete mixing water to lower heat but with daytime temperatures easily reaching 40 degrees Celcius, large amounts of ice must be consumed, adding to project costs. The desalination and freezing processes used to create the ice also adds unwanted greenhouse gas (GHG) emissions.
Many of these issues can be addressed through the use of EcoSmart™ Concrete – concretes with the highest practical level of cement replacement. Research and demonstration projects of EcoSmart Concrete have been thoroughly documented in Canada and the benefits of using fly ash as a cement replacement are becoming increasingly well known. As the use of EcoSmart Concrete in the hot and harsh conditions in the Middle East had not been documented, a testing program for EcoSmart Concrete in the UAE was devised. Such a demonstration of the viability of the material in the region is likely to foster buy-in from potential users.
The EcoSmart Foundation commissioned four organizations – one government and one private facility in both the UAE and Canada – to test samples of concrete for various properties and characteristics. Dubai Central Laboratory (DCL) and UniBeton Ready Mix conducted tests in the UAE while the Canadian Materials Technology Lab (CANMET) and SIMCO Technologies Inc. conducted tests in Canada using material from the UAE.
The key tests conducted:
- Ultimate strength and strength development – determines how strong the concrete gets and how much time it takes to reach that strength
- Chloride penetration – determines how corrosive environments affect concrete
- Heat of hydration – determines how much heat the concrete generates during hardening
- Water demand – determines how much water is required for each concrete mix
The tests showed that EcoSmart Concrete can perform very well in the harsh climate and construction conditions in the Emirates. It was found to be much more effective at resisting corrosion, translating into much longer building lives. Tests conducted by CANMET and UniBeton also showed significant benefits in reducing heat generated by concrete which would reduce both the ice required and the potential for cracking during curing. Another key test finding was a lower water requirement as compared to regular concrete. Saving water in a country that relies on energy-intensive desalination plants is of tremendous importance.
Test results summary:
- Less water required, decreasing the need for desalination
- Less ice required
- Better against salts, reducing building corrosion
- Good long term strength – applicable to all construction scenarios. Low, medium and high strength concretes can be designed.
- Good strength gain – high ambient temperatures help fly ash concretes gain strength at earlier ages
It is apparent from the test series results that EcoSmart Concrete mixes perform better than ordinary Portland cement concretes, both technically and environmentally, and can be used to mitigate several construction challenges in the UAE and throughout the Gulf.
Test reports are available in the Category “Emirates”