Ancient Roman Concrete Reveals Secret to Cutting Carbon Emissions

first_imgAddThis Sharing ButtonsShare to FacebookFacebookFacebookShare to TwitterTwitterTwitterShare to EmailEmailEmailShare to RedditRedditRedditShare to MoreAddThisMoreThe chemical secrets of a concrete Roman breakwater that has spent the last 2,000 years submerged in the Mediterranean Sea have been uncovered by an international team of researchers led by a professor of civil and environmental engineering at the University of California, Berkeley.Analysis of the samples pinpointed why the best Roman concrete was superior to most modern concrete in durability, why its manufacture was less environmentally damaging – and how these improvements could be adopted in the modern world.“It’s not that modern concrete isn’t good – it’s so good we use 19 billion tons of it a year,” says Paulo Monteiro of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory. “The problem is that manufacturing Portland cement accounts for seven percent of the carbon dioxide that industry puts into the air.” Portland cement is the source of the “glue” that holds most modern concrete together. But making it releases carbon from burning fuel, needed to heat a mix of limestone and clays to 1,450 degrees Celsius (2,642 degrees Fahrenheit) – and from the heated limestone (calcium carbonate) itself. Monteiro’s team found that the Romans, by contrast, used much less lime and made it from limestone baked at 900˚ C (1,652˚ F) or lower, requiring far less fuel than Portland cement.Cutting greenhouse gas emissions is one powerful incentive for finding a better way to provide the concrete the world needs; another is the need for stronger, longer-lasting buildings, bridges, and other structures.“In the middle 20th century, concrete structures were designed to last 50 years, and a lot of them are on borrowed time,” Monteiro says. “Now we design buildings to last 100 to 120 years.” Yet Roman harbor installations have survived 2,000 years of chemical attack and wave action underwater.How the Romans did itThe Romans made concrete by mixing lime and volcanic rock. For underwater structures, lime and volcanic ash were mixed to form mortar, and this mortar and volcanic tuff were packed into wooden forms. The seawater instantly triggered a hot chemical reaction. The lime was hydrated – incorporating water molecules into its structure – and reacted with the ash to cement the whole mixture together.Descriptions of volcanic ash have survived from ancient times. First Vitruvius, an engineer for the Emperor Augustus, and later Pliny the Elder recorded that the best maritime concrete was made with ash from volcanic regions of the Gulf of Naples (Pliny died in the eruption of Mt. Vesuvius that buried Pompeii), especially from sites near today’s seaside town of Pozzuoli. Ash with similar mineral characteristics, called pozzolan, is found in many parts of the world.Using experimental facilities from UC Berkeley, Saudi Arabia and Germany, they found that Roman concrete from Pozzuoli differs from the modern kind in several essential ways. One is the kind of glue that binds the concrete’s components together, with the Roman mineral mix producing an exceptionally stable binder. The results revealed a mineral mix with potential applications for high-performance concretes, including the encapsulation of hazardous wastes.“For us, pozzolan is important for its practical applications,” says Monteiro. “It could replace 40 percent of the world’s demand for Portland cement. And there are sources of pozzolan all over the world. Saudi Arabia has mountains of it.”Stronger, longer-lasting modern concrete, made with less fuel and less release of carbon into the atmosphere, may be the legacy of a deeper understanding of how the Romans made their incomparable concrete.(Learn more: Lawrence Berkeley National Lab)AddThis Sharing ButtonsShare to FacebookFacebookFacebookShare to TwitterTwitterTwitterShare to EmailEmailEmailShare to RedditRedditRedditShare to MoreAddThisMorelast_img read more

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Antigua Establishes Regional Travel Bubble – CARICOM Business News

first_img Six Eastern Caribbean countries deemed safe for travel – CDC Oct 16, 2020 St. Lucia records more cases of COVID Oct 16, 2020 Oct 15, 2020 CARICOM-Business-10-July-2020Download CARICOM-Business-10-July-2020 Share this:PrintTwitterFacebookLinkedInLike this:Like Loading… CMO says Saint Lucia at critical stage of COVID-19 outbreak center_img Oct 15, 2020 More deaths from COVID-19 recorded in CARICOM countries,… You may be interested in… Please see the latest edition of the CARICOM Business newsletter which comprises information culled from news entities in the Caribbean and beyond and includes a Foreign Exchange Summary, a Stock Exchange Summary and International Oil Prices. Visitors to Jamaica, Antigua and Barbuda to be tested for COVID-19 – CARICOM Business NewsPlease see the latest edition of the CARICOM Business newsletter which comprises information culled from news entities in the Caribbean and beyond and includes a Foreign Exchange Summary, a Stock Exchange Summary and International Oil Prices. CARICOM-Business-12-June-2020DownloadJune 15, 2020In “Agriculture”Number portability for Antigua and Barbuda – CARICOM Business NewsPlease see the latest edition of the CARICOM Business newsletter which comprises information culled from news entities in the Caribbean and beyond and includes a Foreign Exchange Summary, a Stock Exchange Summary and International Oil Prices. CARICOM Business 23 November, 2018November 26, 2018In “Barbados”Antigua and Barbuda to sell 10% stake in WIOC – CARICOM Business NewsPlease see the latest edition of the CARICOM Business newsletter which comprises information culled from news entities in the Caribbean and beyond and includes a Foreign Exchange Summary, a Stock Exchange Summary and International Oil PricesOctober 29, 2019In “Agriculture”Share this on WhatsApplast_img read more

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Richest football clubs in the world – top 20 in the Money League revealed

first_img 20 20 Football’s Money League has been revealed and it makes good reading for the Premier League’s bean counters.Five of England’s elite feature in the top 10, with nine in the top 20, as compiled by audit firm Deloitte.But which club is number one? Find out, as we count down the top 20, above. 20 20 9. Liverpool – €391.8m in revenue for 2014/15 14. AC Milan – €199.1m in revenue for 2014/15 20 17. Newcastle United – €169.3m in revenue for 2014/15 11. Borussia Dortmund – €280.6m in revenue for 2014/15 20 20 4. Paris Saint-Germain – €480.8m in revenue for 2014/15 12. Tottenham – €257.5m in revenue for 2014/15 18. Everton – €165.1m in revenue for 2014/15 20 20 20. West Ham United – €160.9m in revenue for 2014/15. Find out which clubs make up the top 20, just click the arrow above 6. Manchester City – €463.5m in revenue for 2014/15 20 3. Manchester United – €519.5m in revenue for 2014/15 20 10. Juventus – €323.9m in revenue for 2014/15 20 20 20 20 15. Atletico Madrid – €187.1m in revenue for 2014/15 13. Schalke – €219.7m in revenue for 2014/15 20 16. Roma – €180.4m in revenue for 2014/15 8. Chelsea – €420m in revenue for 2014/15 2. Barcelona – €560.8m in revenue for 2014/15 5. Bayern Munich – €474m in revenue for 2014/15 19. Inter Milan – €164.8m in revenue for 2014/15 20 20 20 7. Arsenal – €435.5m in revenue for 2014/15 20 1. Real Madrid – €577m in revenue for 2014/15last_img read more

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