ôRoman seawater concrete holds the secret to cutting carbon emissionsö
ôRoman seawater concrete holds the secret to cutting carbon emissionsö
(OP)
Came across Catastrophic Anthropogenic Global Warming (enviro-themed press-release-by-government-sponsored CAGW research) this morning:
OK. I'll belief their research. Maybe.
For the structural specialists amongst us, two relevant questions;
Are today's concrete structures "living on borrowed time" as she so breathlessly writes/ Or is the potential failures due to rust, rebar exposure and corrosion, and failure to maintain the steel paint and protection on systems outside of the concrete itself on state-maintained bridges and roadways and dams and locks?
Was Roman concrete so good that we should copy it chemically?
Quote (Monterio)
“Roman seawater concrete holds the secret to cutting carbon emissions”
he 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 Paulo Monteiro of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), a professor of civil and environmental engineering at the University of California, Berkeley.
Analysis of samples provided by team member Marie Jackson 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 Monteiro. “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 that 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. . .
http://phys.org/news/2013-06-roman-seawater-concre...
OK. I'll belief their research. Maybe.
For the structural specialists amongst us, two relevant questions;
Are today's concrete structures "living on borrowed time" as she so breathlessly writes/ Or is the potential failures due to rust, rebar exposure and corrosion, and failure to maintain the steel paint and protection on systems outside of the concrete itself on state-maintained bridges and roadways and dams and locks?
Was Roman concrete so good that we should copy it chemically?






RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
I was under the impression age-related failure of concrete was almost entirely due to rebar corrosion.
Brian C Potter, PE
http://simplesupports.wordpress.com
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
I've seen cores taken out of 50 year old buildings where the reinforcing steel is as perfect and sparkly as the day it was made.
If Roman concrete was superior to what is currently available we would be using it. This isn't playtime where we intentionally use sub-optimal products.
The author found what she set out to find, which is entirely consistent with the findings of other global warmist pseudo- scientists.
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
At the same time, politicos in quasi-Northern cities continue to respond to the slightest threat of snow accumulation with ever-increasing deluges of salt, and some even worse stuff.
The construction and protection systems being specified today have not kept up with such changes in the infrastucture environment.
Our structures are doomed.
Mike Halloran
Pembroke Pines, FL, USA
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
Quando Omni Flunkus Moritati
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
The Romans also didn't have electricity, or cars, or TVs, or plastics, so if we are looking to cut emissions...
Apple v oranges
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
uhhhh....the aqueducts???
RE: ôRoman seawater concrete holds the secret to cutting carbon emissionsö
Concrete is responsible for a significant proportion of CO2 emissions. These emissions can be and should be reduced. Whether we have much to learn from roman practices, I doubt.
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/