New building design withstands earthquake simulation (Video)

Feb 26, 2009
Engineers constructed a four-story, 40-percent replica of a building in a laboratory to test their new technique for bracing high rise buildings in earthquake zones. They simulated an earthquake by pushing and pulling the building with hydraulics. Image: Remy Lequesne

(PhysOrg.com) -- Researchers at the University of Michigan simulated an off-the-charts earthquake in a laboratory to test their new technique for bracing high-rise concrete buildings. Their technique passed the test, withstanding more movement than an earthquake would typically demand.

The engineers used steel fiber-reinforced concrete to develop a better kind of coupling beam that requires less reinforcement and is easier to construct. Coupling beams connect the walls of high rises around openings such as those for doorways, windows, and elevator shafts. These necessary openings can weaken walls.

"We simulated an earthquake that is beyond the range of the maximum credible earthquake and our test was very successful. Our fiber-reinforced concrete beams behaved as well as we expected they would, which is better than the beams in use today," said James Wight, the Frank E. Richart Jr. Collegiate Professor in the U-M Department of Civil and Environmental Engineering.

This video is not supported by your browser at this time.
Engineers at the University of Michigan simulated an off-the-charts earthquake in a laboratory in December to test the strength of their new technique for bracing high-rise buildings.

Working with Wight on this project are Gustavo Parra-Montesinos, an associate professor in the Department of Civil and Environmental Engineering, and Remy Lequesne, a doctoral student in the same department.

Today, coupling beams are difficult to install and require intricate reinforcing bar skeletons. The U-M engineers created a simpler version made of a highly flowable, steel fiber-reinforced concrete.

"We took quite a bit of the cumbersome reinforcement out of the design and replaced it with steel fibers that can be added to the concrete while it's being mixed," Parra-Montesinos said. "Builders could use this fiber-reinforced concrete to build coupling beams that don't require as much reinforcement."

The engineers envision that their brand of beam would be cast off the construction site and then delivered. Nowadays, builders construct the beams, steel skeletons and all, bit by bit as they're building skyscrapers.

Their fiber-reinforced concrete has other benefits as well.

"The cracks that do occur are narrower because the fibers hold them together," Parra-Montesinos said.

The fibers are about one inch long and about the width of a needle.

The engineers performed their test in December on a 40-percent replica of a 4-story building wall that they built in the Structures Laboratory. They applied a peak load of 300,000 pounds against the building, pushing and pulling it with hydraulic actuators.

To quantify the results, they measured the building's drift, which is the motion at the top of the building compared with the motion at the base. In a large earthquake, a building might sustain a drift of 1 to 2 percent. The U-M structure easily withstood a drift of 3 percent.

The new beams could provide an easier, cheaper, stronger way to brace buildings in earthquake-prone areas.

The researchers are now working with a structural design firm to install the beams in several high rises soon to be under construction on the west coast.

Provided by University of Michigan

Explore further: Students take clot-buster for a spin

add to favorites email to friend print save as pdf

Related Stories

Quicker, quake-proof skyscrapers

Dec 04, 2013

Peel back the outer layers of a skyscraper built in an area vulnerable to earthquakes and you'll find a tangle of steel-reinforced concrete beams that span doors, windows and other openings in the structure's ...

Tips For Building Hurricane-Proof Houses

Nov 29, 2005

As less fortunate residents of the devastated Gulf Coast look to rebuild, many are searching for new houses that will be able to weather the next storm.

Gammasphere on a roll

Sep 28, 2004

Gammasphere, the world's most sensitive gamma-ray detector, is already a seasoned traveler, having crossed the United States from Lawrence Berkeley National Laboratory to Argonne by truck, but the 20-ton ins ...

Recommended for you

Students take clot-buster for a spin

2 hours ago

(Phys.org) —In the hands of some Rice University senior engineering students, a fishing rod is more than what it seems. For them, it's a way to help destroy blood clots that threaten lives.

Finnish inventor rethinks design of the axe

7 hours ago

(Phys.org) —Finnish inventor Heikki Kärnä is the man behind the Vipukirves Leveraxe, which is a precision tool for splitting firewood. He designed the tool to make the job easier and more efficient, with ...

Lifting the brakes on fuel efficiency

Apr 18, 2014

The work of a research leader at Michigan Technological University is attracting attention from Michigan's Governor as well as automotive companies around the world. Xiaodi "Scott" Huang of Michigan Tech's ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

WolfAtTheDoor
not rated yet Feb 26, 2009
That's great, but it's kind of a small building.

More news stories

Finnish inventor rethinks design of the axe

(Phys.org) —Finnish inventor Heikki Kärnä is the man behind the Vipukirves Leveraxe, which is a precision tool for splitting firewood. He designed the tool to make the job easier and more efficient, with ...

Students take clot-buster for a spin

(Phys.org) —In the hands of some Rice University senior engineering students, a fishing rod is more than what it seems. For them, it's a way to help destroy blood clots that threaten lives.

First steps towards "Experimental Literature 2.0"

As part of a student's thesis, the Laboratory of Digital Humanities at EPFL has developed an application that aims at rearranging literary works by changing their chapter order. "The human simulation" a saga ...