Dancing Constructs
With natural disasters such as earthquakes and tsunamis laying waste to towns and infrastructure throughout the world — from the United States West Coast to Southeast Asia — many skyscrapers are being built to withstand huge pressures.

For example, working with super-strong materials that can bend, stretch and compress without breaking, scientists and engineers at Lehigh University last year tested a next-generation "self-centering" system that uses gigantic steel bands to hold building columns and beams in place during an earthquake. As IMT previously noted:

In allowing the beams and columns to separate, rock and twist independently of one another, the rope-like steel bands — encased in plastic — are meant to prevent a building frame from buckling during an earthquake. The system also uses friction plates that help dissipate the quake's energy. After the tremors subside, the steel bands pull the beams and columns back to their original positions.

Lehigh's Center for Advanced Technology for Large Structural Systems (ATLSS) Engineering Research Center's structural testing lab, where scientists have tested a next-generation "self-centering" system for buildings during earthquakes
Credit: AP/ABC News

More recent, researchers at the University of Buffalo in upstate New York last month announced the development and successful testing of the first seismic design methodology for bridge towers that respond to ground motions by literally "jumping" a few inches off the ground.

The university's engineers developed a design procedure in which the steel truss tower's legs, anchored strongly to their footing, are disconnected from their base and briefly uplifted by a small amount if significant ground motions occur. The methodology will not allow uplifts to exceed limits considered safe by the design procedure and dictated by the tower design, local conditions and the need for the tower to return safely to its original position.

During a series of tests on a state-of-the-art "shake table," the experimental truss tower fitted with devices hysteretic or viscous dampers — which were inserted at the base of the towers to allow the tower to rock while absorbing part of "the earthquake" energy — was subjected to ground motions simulating the 1994 Northridge, California earthquake. (Testing also was conducted without any devices attached.) During testing, the tower's legs typically uplifted nearly two inches in the air for less than a second. For some of the free-rocking cases, the tower legs lifted nearly four inches.

All of the tests were successful.

Although engineers previously have employed the concept, such as in the approach spans of the Lions Gate Bridge in Vancouver, British Columbia, the University of Buffalo methodology is the first to be established for this application.

"Professional engineers are starting to recognize that it is economical to allow this type of rocking in their designs, as long as the structure remains stable and the speed with which the legs come down is carefully controlled to minimize the forces that develop during the rocking," said Michel Bruneau, Ph.D., director of MCEER and University of Buffalo professor of civil, structural and environmental engineering, who developed the new approach with Michael Pollino, a doctoral candidate in the university's Department of Civil, Structural and Environmental Engineering.

These "bridges that 'dance' during earthquakes could be the safest and least expensive to build, retrofit and repair," according to earthquake engineers at the university and MCEER.

(See also: "Shape-shifting Structures Adapt to Environment" and "Shake, Rattle, Roll: Advances In Earthquake-Proof Buildings")

Self-Healing House
A high-tech villa designed to resist earthquakes by "self-healing" cracks in its own walls and monitoring vibrations through an intelligent sensor network will be built on a Greek mountainside.

The house walls will be built from novel load bearing steel frames and high-strength gypsum board. They will also contain wireless, battery-less sensors and radio frequency identification (RFID) tags that collect vast amounts of data about the building over times, such as any stresses and vibrations, temperature, humidity and gas levels.

According to the University of Leeds:

The University of Leeds' NanoManufacturing Institute (NMI) will play a crucial role in the £9.5 million European Union-funded project by developing special walls for the house that contain nano-polymer particles — these will turn into a liquid when squeezed under pressure, flow into the cracks, and then harden to form a solid material.

"We're looking to use polymers in much tougher situations than ever before on a larger scale," said Dr. Terry Wilkins, professor and NMI chief executive, in the university newsletter The Reporter.

Photo Credit: North Valley Animal Disaster Group

Smart Buildings
The true houses of the future will look the same as always, only with something extra that the other houses never had: brains.

This according to Daniel H. Wilson, renowned author of "How to Survive a Robot Uprising" and the recent "Where's My Jetpack?" in a recent Popular Mechanics column on the realistic "home of the future."

Right now, "smart home" technology is available off the shelf; home automation enthusiasts have access to all kinds of gadgets that can make life simpler — and more complicated. The key goal for home automation is to give the occupant total control over the house from anywhere, which is why most home automation devices require a central personal computer to provide control and to run programs. Currently, there is an entire home automation industry ready to supply gadgets to that end.

Sensors such as cameras, motion detectors or water leak detectors already can be used to monitor who is in your driveway, trigger exterior lights when people approach or constantly check for broken water pipes. Moreover, when it comes to privacy, a building with a network of motion detectors can improve the efficiency and safety of the building while protecting the privacy of individual inhabitants.

According to New Scientist:

Such systems could use their knowledge of where groups congregate to turn down the air conditioning when there are only a few people in one part of the building, for example. In an emergency, electronic signs could direct people to the nearest available escape route when one becomes congested. Rather than using cameras, which would invade people's privacy, Christopher Wren at the Mitsubishi Electric Research Laboratory (MERL) in Cambridge, Massachusetts, is using "dumb" infrared motion sensors similar to those used to control automatic lights.

"Imagine peeling the roof off the building and watching people go about their lives, like in an ant farm," Wren said in a New Scientist report in April. "You can't identify individual ants or keep track of them as they scurry past each other, but you can watch as they move food into the nest or dig chambers."

And effectors can be used to automatically water plants, remotely raise and lower blinds, or feed your pets.

On the other hand, artificial intelligence can breathe life into a robotic home. Sinking smart robotics technology into the infrastructure of a home is called "ubiquitous computing."

While there is nothing novel about a remote-controlled house, "intelligent environments" are another matter. An entire field of research focuses on blending high-tech computing into the home environment. Instead of interacting with a box on a table, occupants of the future will interact with a helpful, intelligent and friendly robotic home.

"Smart houses are a reality," Wilson writes. However, while home automation devices are available, they require a lot of hard work; and the end result is a remote-control house rather than the slick, bubble-on-a-pedestal, fully-automatic-everything type of house from The Jetsons that we envisioned in the 1950s.

Resources

Bridges Will Rock -- Safely -- with New Quake Design
University of Buffalo

Smart House: Your So-Called Sci-Fi Life
by Daniel H. Wilson
Popular Mechanics, May 7, 2007

'Self-healing' house in Greece will dare to defy nature
The Reporter (University of Leeds), March 26, 2007

Buildings could save energy by spying on inhabitants
by Celeste Biever
New Scientist magazine, April 28, 2007 (issue 2601)