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Roman Seawater Concrete Holds the Secret to Cutting Carbon Emissions
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Jun 4, 2013, 9:57:26 PM6/4/13
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Roman Seawater Concrete Holds the Secret to Cutting Carbon Emissions
Berkeley Lab scientists and their colleagues have
discovered the properties that made ancient Roman
concrete sustainable and durable
Paul Preuss
Berkeley Lab News Center
510-486-6249
paul_...@lbl.gov
News Release
Tuesday, June 4, 2013
Drill core of volcanic ash-hydrated lime mortar from the
ancient port of Baiae in Pozzuloi Bay. Yellowish
inclusions are pumice, dark stony fragments are lava,
gray areas consist of other volcanic crystalline
materials, and white spots are lime. Inset is a scanning
electron microscope image of the special Al-tobermorite
crystals that are key to the superior quality of Roman
seawater concrete. (Click on image for best resolution.)
The 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 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 it
The 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.
Pozzuoli Bay defines the northwestern region of the Bay
of Naples. The concrete sample examined at the Advanced
Light Source by Berkeley researchers, BAI.06.03, is from
the harbor of Baiae, one of many ancient underwater sites
in the region. Black lines indicate caldera rims, and red
areas are volcanic craters. (Click on image for best
resolution.)
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 beamlines 5.3.2.1, 5.3.2.2, 12.2.2 and 12.3.2 at
Berkeley Lab’s Advanced Light Source (ALS), along with
other experimental facilities at UC Berkeley, the King
Abdullah University of Science and Technology in Saudi
Arabia, and the BESSY synchrotron in Germany, Monteiro
and his colleagues investigated maritime concrete from
Pozzuoli Bay. They found that Roman concrete differs from
the modern kind in several essential ways.
One is the kind of glue that binds the concrete’s
components together. In concrete made with Portland
cement this is a compound of calcium, silicates, and
hydrates (C-S-H). Roman concrete produces a significantly
different compound, with added aluminum and less silicon.
The resulting calcium-aluminum-silicate-hydrate (C-A-S-H)
is an exceptionally stable binder.
At ALS beamlines 5.3.2.1 and 5.3.2.2, x-ray spectroscopy
showed that the specific way the aluminum substitutes for
silicon in the C-A-S-H may be the key to the cohesion and
stability of the seawater concrete.
Another striking contribution of the Monteiro team
concerns the hydration products in concrete. In theory,
C-S-H in concrete made with Portland cement resembles a
combination of naturally occurring layered minerals,
called tobermorite and jennite. Unfortunately these ideal
crystalline structures are nowhere to be found in
conventional modern concrete.
Tobermorite does occur in the mortar of ancient seawater
concrete, however. High-pressure x-ray diffraction
experiments at ALS beamline 12.2.2 measured its
mechanical properties and, for the first time, clarified
the role of aluminum in its crystal lattice. Al-
tobermorite (Al for aluminum) has a greater stiffness
than poorly crystalline C-A-S-H and provides a model for
concrete strength and durability in the future.
Finally, microscopic studies at ALS beamline 12.3.2
identified the other minerals in the Roman samples.
Integration of the results from the various beamlines
revealed the minerals’ potential applications for high-
performance concretes, including the encapsulation of
hazardous wastes.
Lessons for the future
Environmentally friendly modern concretes already include
volcanic ash or fly ash from coal-burning power plants as
partial substitutes for Portland cement, with good
results. These blended cements also produce C-A-S-H, but
their long-term performance could not be determined until
the Monteiro team analyzed Roman concrete.
Their analyses showed that the Roman recipe needed less
than 10 percent lime by weight, made at two-thirds or
less the temperature required by Portland cement. Lime
reacting with aluminum-rich pozzolan ash and seawater
formed highly stable C-A-S-H and Al-tobermorite, insuring
strength and longevity. Both the materials and the way
the Romans used them hold lessons for the future.
“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 doesn’t have any fly ash, but it has mountains of
pozzolan.”
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.
This work was supported by King Abdullah University of
Science and Technology, the Loeb Classical Library
Foundation at Harvard University, and DOE’s Office of
Science, which also supports the Advanced Light Source.
Samples of Roman maritime concrete were provided by Marie
Jackson and by the ROMACONS drilling program, sponsored
by CTG Italcementi of Bergamo, Italy.
###
Scientific contacts: Paulo Monteiro,
mont...@ce.berkeley.edu, 510-643-8251; Marie Jackson,
mdja...@berkeley.edu, 928-853-7967
For more information, read the UC Berkeley press release
at http://newscenter.berkeley.edu/2013/06/04/roman-
concrete/.
“Material and elastic properties of Al-tobermorite in
ancient Roman seawater concrete,” by Marie D. Jackson,
Juhyuk Moon, Emanuele Gotti, Rae Taylor, Abdul-Hamid
Emwas, Cagla Meral, Peter Guttmann, Pierre Levitz, Hans-
Rudolf Wenk, and Paulo J. M. Monteiro, appears in the
Journal of the American Ceramic Society.
“Unlocking the secrets of Al-tobermorite in Roman
seawater concrete,” by Marie D. Jackson, Sejung Rosie
Chae, Sean R. Mulcahy, Cagla Meral, Rae Taylor, Penghui
Li, Abdul-Hamid Emwas, Juhyuk Moon, Seyoon Yoon, Gabriele
Vola, Hans-Rudolf Wenk, and Paulo J. M. Monteiro, will
appear in American Mineralogist.
The Advanced Light Source is a third-generation
synchrotron light source producing light in the x-ray
region of the spectrum that is a billion times brighter
than the sun. A DOE national user facility, the ALS
attracts scientists from around the world and supports
its users in doing outstanding science in a safe
environment. For more information visit www-als.lbl.gov/.
Lawrence Berkeley National Laboratory addresses the
world’s most urgent scientific challenges by advancing
sustainable energy, protecting human health, creating new
materials, and revealing the origin and fate of the
universe. Founded in 1931, Berkeley Lab’s scientific
expertise has been recognized with 13 Nobel prizes. The
University of California manages Berkeley Lab for the
U.S. Department of Energy’s Office of Science. For more,
visit www.lbl.gov.
DOE’s Office of Science is the single largest supporter
of basic research in the physical sciences in the United
States, and is working to address some of the most
pressing challenges of our time. For more information,
please visit the Office of Science website at
science.energy.gov.
A U.S. Department of Energy National Laboratory Operated
by the University of California
More at:
http://newscenter.lbl.gov/news-releases/2013/06/04/roman-concrete/
Jai Maharaj, Jyotishi
Om Shanti
http://groups.google.com/group/alt.fan.jai-maharaj
o o o
o Not for commercial use. Solely to be fairly used
for the educational purposes of research and open
discussion. The contents of this post may not have been
authored by, and do not necessarily represent the opinion
of the poster. The contents are protected by copyright
law and the exemption for fair use of copyrighted works.
o If you send private e-mail to me, it will likely
not be read, considered or answered if it does not
contain your full legal name, current e-mail and postal
addresses, and live-voice telephone number.
o Posted for information and discussion. Views
expressed by others are not necessarily those of the
poster who may or may not have read the article.
FAIR USE NOTICE: This article may contain copyrighted
material the use of which may or may not have been
specifically authorized by the copyright owner. This
material is being made available in efforts to advance
the understanding of environmental, political, human
rights, economic, democratic, scientific, social, and
cultural, etc., issues. It is believed that this
constitutes a 'fair use' of any such copyrighted material
as provided for in section 107 of the US Copyright Law.
In accordance with Title 17 U.S.C. Section 107, the
material on this site is distributed without profit to
those who have expressed a prior interest in receiving
the included information for research, comment,
discussion and educational purposes by subscribing to
USENET newsgroups or visiting web sites. For more
information go to:
http://www.law.cornell.edu/uscode/17/107.shtml
If you wish to use copyrighted material from this article
for purposes of your own that go beyond 'fair use', you
must obtain permission from the copyright owner.
Since newsgroup posts are being removed by forgery by one
or more net terrorists, this post may be reposted several
times.
Berkeley Lab scientists and their colleagues have
discovered the properties that made ancient Roman
concrete sustainable and durable
Paul Preuss
Berkeley Lab News Center
510-486-6249
paul_...@lbl.gov
News Release
Tuesday, June 4, 2013
Drill core of volcanic ash-hydrated lime mortar from the
ancient port of Baiae in Pozzuloi Bay. Yellowish
inclusions are pumice, dark stony fragments are lava,
gray areas consist of other volcanic crystalline
materials, and white spots are lime. Inset is a scanning
electron microscope image of the special Al-tobermorite
crystals that are key to the superior quality of Roman
seawater concrete. (Click on image for best resolution.)
The 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 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 it
The 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.
Pozzuoli Bay defines the northwestern region of the Bay
of Naples. The concrete sample examined at the Advanced
Light Source by Berkeley researchers, BAI.06.03, is from
the harbor of Baiae, one of many ancient underwater sites
in the region. Black lines indicate caldera rims, and red
areas are volcanic craters. (Click on image for best
resolution.)
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 beamlines 5.3.2.1, 5.3.2.2, 12.2.2 and 12.3.2 at
Berkeley Lab’s Advanced Light Source (ALS), along with
other experimental facilities at UC Berkeley, the King
Abdullah University of Science and Technology in Saudi
Arabia, and the BESSY synchrotron in Germany, Monteiro
and his colleagues investigated maritime concrete from
Pozzuoli Bay. They found that Roman concrete differs from
the modern kind in several essential ways.
One is the kind of glue that binds the concrete’s
components together. In concrete made with Portland
cement this is a compound of calcium, silicates, and
hydrates (C-S-H). Roman concrete produces a significantly
different compound, with added aluminum and less silicon.
The resulting calcium-aluminum-silicate-hydrate (C-A-S-H)
is an exceptionally stable binder.
At ALS beamlines 5.3.2.1 and 5.3.2.2, x-ray spectroscopy
showed that the specific way the aluminum substitutes for
silicon in the C-A-S-H may be the key to the cohesion and
stability of the seawater concrete.
Another striking contribution of the Monteiro team
concerns the hydration products in concrete. In theory,
C-S-H in concrete made with Portland cement resembles a
combination of naturally occurring layered minerals,
called tobermorite and jennite. Unfortunately these ideal
crystalline structures are nowhere to be found in
conventional modern concrete.
Tobermorite does occur in the mortar of ancient seawater
concrete, however. High-pressure x-ray diffraction
experiments at ALS beamline 12.2.2 measured its
mechanical properties and, for the first time, clarified
the role of aluminum in its crystal lattice. Al-
tobermorite (Al for aluminum) has a greater stiffness
than poorly crystalline C-A-S-H and provides a model for
concrete strength and durability in the future.
Finally, microscopic studies at ALS beamline 12.3.2
identified the other minerals in the Roman samples.
Integration of the results from the various beamlines
revealed the minerals’ potential applications for high-
performance concretes, including the encapsulation of
hazardous wastes.
Lessons for the future
Environmentally friendly modern concretes already include
volcanic ash or fly ash from coal-burning power plants as
partial substitutes for Portland cement, with good
results. These blended cements also produce C-A-S-H, but
their long-term performance could not be determined until
the Monteiro team analyzed Roman concrete.
Their analyses showed that the Roman recipe needed less
than 10 percent lime by weight, made at two-thirds or
less the temperature required by Portland cement. Lime
reacting with aluminum-rich pozzolan ash and seawater
formed highly stable C-A-S-H and Al-tobermorite, insuring
strength and longevity. Both the materials and the way
the Romans used them hold lessons for the future.
“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 doesn’t have any fly ash, but it has mountains of
pozzolan.”
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.
This work was supported by King Abdullah University of
Science and Technology, the Loeb Classical Library
Foundation at Harvard University, and DOE’s Office of
Science, which also supports the Advanced Light Source.
Samples of Roman maritime concrete were provided by Marie
Jackson and by the ROMACONS drilling program, sponsored
by CTG Italcementi of Bergamo, Italy.
###
Scientific contacts: Paulo Monteiro,
mont...@ce.berkeley.edu, 510-643-8251; Marie Jackson,
mdja...@berkeley.edu, 928-853-7967
For more information, read the UC Berkeley press release
at http://newscenter.berkeley.edu/2013/06/04/roman-
concrete/.
“Material and elastic properties of Al-tobermorite in
ancient Roman seawater concrete,” by Marie D. Jackson,
Juhyuk Moon, Emanuele Gotti, Rae Taylor, Abdul-Hamid
Emwas, Cagla Meral, Peter Guttmann, Pierre Levitz, Hans-
Rudolf Wenk, and Paulo J. M. Monteiro, appears in the
Journal of the American Ceramic Society.
“Unlocking the secrets of Al-tobermorite in Roman
seawater concrete,” by Marie D. Jackson, Sejung Rosie
Chae, Sean R. Mulcahy, Cagla Meral, Rae Taylor, Penghui
Li, Abdul-Hamid Emwas, Juhyuk Moon, Seyoon Yoon, Gabriele
Vola, Hans-Rudolf Wenk, and Paulo J. M. Monteiro, will
appear in American Mineralogist.
The Advanced Light Source is a third-generation
synchrotron light source producing light in the x-ray
region of the spectrum that is a billion times brighter
than the sun. A DOE national user facility, the ALS
attracts scientists from around the world and supports
its users in doing outstanding science in a safe
environment. For more information visit www-als.lbl.gov/.
Lawrence Berkeley National Laboratory addresses the
world’s most urgent scientific challenges by advancing
sustainable energy, protecting human health, creating new
materials, and revealing the origin and fate of the
universe. Founded in 1931, Berkeley Lab’s scientific
expertise has been recognized with 13 Nobel prizes. The
University of California manages Berkeley Lab for the
U.S. Department of Energy’s Office of Science. For more,
visit www.lbl.gov.
DOE’s Office of Science is the single largest supporter
of basic research in the physical sciences in the United
States, and is working to address some of the most
pressing challenges of our time. For more information,
please visit the Office of Science website at
science.energy.gov.
A U.S. Department of Energy National Laboratory Operated
by the University of California
More at:
http://newscenter.lbl.gov/news-releases/2013/06/04/roman-concrete/
Jai Maharaj, Jyotishi
Om Shanti
http://groups.google.com/group/alt.fan.jai-maharaj
o o o
o Not for commercial use. Solely to be fairly used
for the educational purposes of research and open
discussion. The contents of this post may not have been
authored by, and do not necessarily represent the opinion
of the poster. The contents are protected by copyright
law and the exemption for fair use of copyrighted works.
o If you send private e-mail to me, it will likely
not be read, considered or answered if it does not
contain your full legal name, current e-mail and postal
addresses, and live-voice telephone number.
o Posted for information and discussion. Views
expressed by others are not necessarily those of the
poster who may or may not have read the article.
FAIR USE NOTICE: This article may contain copyrighted
material the use of which may or may not have been
specifically authorized by the copyright owner. This
material is being made available in efforts to advance
the understanding of environmental, political, human
rights, economic, democratic, scientific, social, and
cultural, etc., issues. It is believed that this
constitutes a 'fair use' of any such copyrighted material
as provided for in section 107 of the US Copyright Law.
In accordance with Title 17 U.S.C. Section 107, the
material on this site is distributed without profit to
those who have expressed a prior interest in receiving
the included information for research, comment,
discussion and educational purposes by subscribing to
USENET newsgroups or visiting web sites. For more
information go to:
http://www.law.cornell.edu/uscode/17/107.shtml
If you wish to use copyrighted material from this article
for purposes of your own that go beyond 'fair use', you
must obtain permission from the copyright owner.
Since newsgroup posts are being removed by forgery by one
or more net terrorists, this post may be reposted several
times.
Percival
Jun 5, 2013, 4:46:14 AM6/5/13
to
On 6/4/2013 6:57 PM, Dr. Jai Maharaj wrote:
> Roman Seawater Concrete Holds the Secret to Cutting Carbon Emissions
>
> Berkeley Lab scientists and their colleagues have
> discovered the properties that made ancient Roman
> concrete sustainable and durable
(snip)
> Roman Seawater Concrete Holds the Secret to Cutting Carbon Emissions
>
> Berkeley Lab scientists and their colleagues have
> discovered the properties that made ancient Roman
> concrete sustainable and durable
> The chemical secrets of a concrete Roman breakwater that
> has spent the last 2,000 years submerged in the
> Mediterranean Sea
I'm gonna guess that the Romans didn't pour that breakwater under water.
So, when did it become submerged?
Mark L. Fergerson
dlzc
Jun 5, 2013, 10:12:51 AM6/5/13
to
Dear Percival:
On Wednesday, June 5, 2013 1:46:14 AM UTC-7, Percival wrote:
> On 6/4/2013 6:57 PM, Dr. Jai Maharaj wrote:
>
> > Roman Seawater Concrete Holds the Secret to
> > Cutting Carbon Emissions
...
http://mediterranee.revues.org/1952?lang=en
I know that concrete hardens more if you keep is submerged, As to forming anything recognizable...
David A. Smith
On Wednesday, June 5, 2013 1:46:14 AM UTC-7, Percival wrote:
> On 6/4/2013 6:57 PM, Dr. Jai Maharaj wrote:
>
> > Roman Seawater Concrete Holds the Secret to
> > Cutting Carbon Emissions
> I'm gonna guess that the Romans didn't pour that
> breakwater under water.
>
> So, when did it become submerged?
This reads like they poured their structures in place, submerged:
> breakwater under water.
>
> So, when did it become submerged?
http://mediterranee.revues.org/1952?lang=en
I know that concrete hardens more if you keep is submerged, As to forming anything recognizable...
David A. Smith
Bruce Sinclair
Jun 5, 2013, 7:16:18 PM6/5/13
to
In article <79d00543-abd6-4cf2...@googlegroups.com>, dlzc <dl...@cox.net> wrote:
>Dear Percival:
>On Wednesday, June 5, 2013 1:46:14 AM UTC-7, Percival wrote:
>> On 6/4/2013 6:57 PM, Dr. Jai Maharaj wrote:
>> > Roman Seawater Concrete Holds the Secret to
>> > Cutting Carbon Emissions
>....
>Dear Percival:
>On Wednesday, June 5, 2013 1:46:14 AM UTC-7, Percival wrote:
>> On 6/4/2013 6:57 PM, Dr. Jai Maharaj wrote:
>> > Roman Seawater Concrete Holds the Secret to
>> > Cutting Carbon Emissions
>> I'm gonna guess that the Romans didn't pour that
>> breakwater under water.
>> So, when did it become submerged?
>
>This reads like they poured their structures in place, submerged:
>http://mediterranee.revues.org/1952?lang=en
>I know that concrete hardens more if you keep is submerged, As to forming
> anything recognizable...
I recall going to a chemistry session on concrete years ago, mostly to find
>> breakwater under water.
>> So, when did it become submerged?
>
>This reads like they poured their structures in place, submerged:
>http://mediterranee.revues.org/1952?lang=en
>I know that concrete hardens more if you keep is submerged, As to forming
> anything recognizable...
out what anyone could talk about for 3 hours about concrete. :)
It was actually fascinating, and there are many many types/formulas, some of
which will apparently set underwater. What did the Romans know about it is
another question. :)
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