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Experimental concrete that patches up cracks by itself is to undergo outdoor testing. The concrete contains limestone-producing bacteria, which are activated by corrosive rainwater working its way into the structure. The new material could potentially increase the service life of the concrete - with considerable cost savings as a result. The work is taking place at Delft Technical University, the Netherlands. It is the brainchild of microbiologist Henk Jonkers and concrete technologist Eric Schlangen. If all goes well, Dr Jonkers says they could start the process of commercialising the system in 2-3 years.

new water-repellant concrete impregnated with tiny superstrong fibers promises to leave roads and bridges free of major cracks for up to 120 years. University of Wisconsin-Milwaukee civil engineers have developed a concrete mix that is durable and superhydrophobic. They call it Superhydrophobic Engineered Cementitious Composite (SECC). Preventing normally porous concrete from absorbing water means that liquid can’t get inside, freeze and cause it to crack. The concrete’s unusual characteristics, including being significantly more ductile than traditional concrete, means that cracks that do form do not propagate and cause failure. “Our architecture allows the material to withstand four times the compression...

Researchers at MIT are seeking to redesign concrete — the most widely used human-made material in the world — by following nature’s blueprints. In a paper published online in the journal Construction and Building Materials, the team contrasts cement paste — concrete’s binding ingredient — with the structure and properties of natural materials such as bones, shells, and deep-sea sponges. As the researchers observed, these biological materials are exceptionally strong and durable, thanks in part to their precise assembly of structures at multiple length scales, from the molecular to the macro, or visible, level. From their observations, the team, led...

Uncovering the secrets of the Great Pyramid August 29 2004 at 01:18PM By Annick Benoist Paris - Two French amateur archaelogists this week published a book in which they claim to have located the secret burial chamber of the Pyramid of Cheops near Cairo, the largest pyramid ever built. According to the study of the Great Pyramid, a fourth, undiscovered room lies underneath its so-called Queen's chamber, and is likely to have been the burial chamber for Cheops, an Egyptian pharaoh who ruled from 2560 to 2532 BC. Cheops' final resting place has never been found despite decades of investigation...

CAIRO, Egypt (AP) - A pair of French Egyptologists who suspect they have found a previously unknown chamber in the Great Pyramid urged Egypt's antiquities chief to reconsider letting them test their theory by drilling new holes in the 4,600-year-old structure. Jean Yves Verd'hurt and fellow Frenchman Gilles Dormion, who has studied pyramid construction for more than 20 years, are expected to raise their views during the ninth International Congress of Egyptologists in Grenoble, France, which starts Monday. They also published a book about their theory this week. Standing in their way is Zahi Hawass, the director of Egypt's Supreme...

Jean-Pierre Houdin -- who was rebuffed three years ago by Egypt in his appeal for a probe into how the Pyramid was built -- said 3-D simulation and data from a U.S. egyptologist, Bob Brier, pointed to two secret chambers in the heart of the structure. The rooms would have housed furniture for use in the afterlife by the pharaoh Khufu, also known as Cheops in Greek, he told a press conference. "I am convinced there are antechambers in this pyramid. What I want is to find them," he said. In March 2007, Houdin advanced the theory that the Great...

Using cutting edge technology, Egyptologist Bob Brier of the C.W. Post Campus of Long Island University delved into the only standing wonder of the ancient world, the Great Pyramid, and uncovered the mystery behind cracks in the massive Egyptian structure, unearthing a new room along the way. Brier, French architect Jean-Pierre Houdin and a team of software specialists from Dassault Systems in Paris used 3-D modeling software to determine that the burial chamber's stone support beams cracked as final construction of the Giza wonder was near completion 4,500 years ago. The team discovered that the cracks occurred when three...

A French architect said on Friday he had cracked a 4,500-year-old mystery surrounding Egypt's Great Pyramid, saying it was built from the inside out. Previous theories have suggested Pharaoh Khufu's tomb, the last surviving example of the seven great wonders of antiquity, was built using either a vast frontal ramp or a ramp in a corkscrew shape around the exterior to haul up the stonework. But flouting previous wisdom, Jean-Pierre Houdin said advanced 3D technology had shown the main ramp which was used to haul the massive stones to the apex was contained 10-15 meters beneath the outer skin, tracing...

PARIS - A French architect claimed Friday to have uncovered the mystery about how Egypt's Great Pyramid of Khufu was built — with use of a spiral ramp to hoist huge stone blocks into place. The construction of the Great Pyramid 4,500 years ago by Khufu, a ruler also known as Cheops, has long befuddled scientists as to how its 3 million stone blocks weighing 2.5 tons each were lifted into place. Ending eight years of study on the subject, architect Jean-Pierre Houdin released his findings and a computerized 3-D mockup showing how workers would have erected the pyramid at...

Meteorites from under the pyramids Samples of rock and fragments of pyramid walls brought from Egypt are being examined at the AGH University of Science and Technology. It is very likely that meteorites had dropped near the pyramids. The material was collected during the December expedition of geologists. Another aim of the expedition was to study some geoglyphics, i.e. gigantic pictures drawn on the ground. According to "Dziennik Polski", the scientists were intrigued by some unusual structures, which resembled craters formed after meteorites hit the ground. They noticed them when analysing satellite pictures of areas north of the great pyramids...

Like millions of tourists, from the Ancient Greeks on, the Blairs may have been victims of one of the world's oldest confidence tricks when they walked round the Pyramids on the Prime Minister's holiday trip to Egypt. To the uninitiated eye, the 2.3 million blocks of stones rising to a 146-metre peak on the 4,500-year-old Great Pyramid near Cairo look as solid as pure granite. But French architects and scientists believe they are nothing more than weathered concrete blocks, moulded on the spot, stone by stone and layer by layer, from the ground upwards. The theory, being explored by ...

All of the current theories -- a long, straight ramp, a ramp that corkscrewed around the outside of the pyramid, or cranelike shadoufs (used in Egypt until recently for irrigating fields) -- have serious flaws... architect Jean-Pierre Houdin and I presented a radical new theory: that blocks of stone were raised to the very top of the pyramid on an internal ramp. We gave what we felt was strong evidence for the theory, which explains a French team's microgravemetric survey in the 1980s that recorded variations in the density of the pyramid... an image from the survey may show a...

Apr. 1, 2007 12:21 | Updated Apr. 1, 2007 14:53War of the pyramid theorists By YANIV SALAMA-SCHEER AND JORG LUYKEN Every significant historical site goes through periods of the day when the surrounding environment make a visit truly worthwhile. At the pyramids of Giza, the view at sunset can push away the claustrophobic memory of the flocks of tourists and local souvenir-sellers who dominate the site earlier in the day. In the hush of sunset, visitors can appreciate the beautiful symmetry of these ancient tombs as the half-light of dusk eradicates the imperfections of age that are evident during the...

Scientists say pyramids could be concrete April 23, 2008 Scientists are taking a new look at Egypt's pyramids to see if some of the blocks could have been made from concrete. Linn W. Hobbs, a materials science professor at Massachusetts Institute of Technology, told The Boston Globe there is a chance ancient Egyptians could have cast the blocks from synthetic material instead of carving them from quarries. Scientists have long believed Romans were the first to use structural concrete. Undergraduates in MIT's Materials in Human Experience class are building a scale-model pyramid made of quarried limestone and blocks cast from...

Mathematics in Ancient Egypt the Ancient Egyptians possess an ingenious skill for calculation? Assem Deif* works out an ancient problem The Greeks developed mathematics as a deductive science that reached its climax with Euclid of Alexandria in his masterpiece The Elements. Before that, during the ancient Egyptian era, mathematics was an inductive discipline of a utilitarian nature used to perform practical tasks such as flood control or land measurement using rope. It has been suggested that mathematics then amounted to no more than the two-times table and the ability to find two-thirds of any number. The whole structure of Egyptian...

Riddle Of The Great Pyramids Of Giza: Professor Finds Some Building Blocks Were Concrete In partially solving a mystery that has baffled archeologists for centuries, a Drexel University professor has determined that the Great Pyramids of Giza were constructed with a combination of not only carved stones but the first blocks of limestone-based concrete cast by any civilization. Picture of the Great Pyramid (Kheops pyramid). (Taken by Alex lbh in April 2005 / Courtesy of Wikipedia) Ads by Google Michel Barsoum, professor of materials engineering, shows in a peer-reviewed paper to be published Dec. 1 in the Journal of...

The Ancient Egyptians built their great Pyramids by pouring concrete into blocks high on the site rather than hauling up giant stones, according to a new Franco-American study. The research, by materials scientists from national institutions, adds fuel to a theory that the pharaohs’ craftsmen had enough skill and materials at hand to cast the two-tonne limestone blocks that dress the Cheops and other Pyramids. Despite mounting support from scientists, Egyptologists have rejected the concrete claim, first made in the late 1970s by Joseph Davidovits, a French chemist. The stones, say the historians and archeologists, were all carved from nearby...

Research team recreates ancient underwater concrete technology A University of Colorado at Boulder professor and his colleagues have taken a page from the writings of an ancient Roman architect and built an underwater concrete pier in the manner of those set in the Mediterranean Sea 2,000 years ago. CU-Boulder history Professor Robert Hohlfelder, an internationally known underwater archaeologist, said scholars have long been in awe of the engineering feats of the early Romans. A former co-director of the international Caesarea Ancient Harbor Excavation Project, he said the research effort was spurred by the stunning hydraulic concrete efforts undertaken at...

Who Built the Pyramids? Not slaves. archeaologist Mark Lehner digging deeper, discovers a city of privileged workers. by Jonathan Shaw The pyramids and the Great Sphinx rise inexplicably from the desert at Giza, relics of a vanished culture. They dwarf the approaching sprawl of modern Cairo, a city of 16 million. The largest pyramid, built for the Pharaoh Khufu around 2530 B.C. and intended to last an eternity, was until early in the twentieth century the biggest building on the planet. To raise it, laborers moved into position six and a half million tons of stone—some in blocks as large...

...using synchrotrons to analyse the synthetic turquoise that was popular during the reign of Pharaoh Akhenaten around 1300BC. Archaeologist Dr Mark Eccleston... says Egyptian 'faience', a fine-glazed quartz ceramic of distinct turquoise colour, was a common material used in items ranging from simple beads to religious artefacts. He says while it was known that larger factories were used to produce the faience, his research has shown less prestigious pieces could also have been produced in ovens in household courtyards... "Large state industries were effectively sub-contracting labour and the household would get something in return, for example more food." ...Eccleston says...