Freeway beams are undergoing quake testing

A Brigham Young University professor of civil engineering is putting tons of pressure on freeway support beams.

Kyle Rollins wants to see if the support piles will withstand the sudden and immense pressure of an earthquake.

To do so, he's working with the Utah Department of Transportation to conduct a series of tests on the supports at the intersection of Redwood Road and U-201.

Using a 39-ton rocket-powered weight known as the Statnamic, Rollins delivers 800,000 pounds of downward force against a 16-inch steel pile foundation, the kind used to support freeway bridges and multi-level buildings.

Sensors set alongside the pile record the pile's reaction to the pressure. The data collected will then help transportation officials understand how a major earthquake would affect the local freeway systems.

It costs $10,000 for Rollins to conduct two series of tests because the Statnamic equipment is already owned by UDOT and has been used in I-I5 reconstruction as well as across the country.

"It's helped us because we can use higher-capacity piles and not as many piles," said Jim Higbee, UDOT Geotechnical Oversight Engineer. "That saves money."

The tests Rollins is conducting look at vertical capacity, said Blaine Leonard, UDOT research project manager.

Rollins said the tests on Thursday were delayed because someone had stolen the 350-lb lock piece from the top of the testing tower and another one had to be created. He intends to finish his tests Friday.

Rollins is an expert in earthquake simulation and liquefaction, the condition that occurs when an earthquake causes an increase in water pressure, turning stable soil into something like a vat of mud.

He has conducted simulations in California in the San Francisco Bay area and in South Carolina.

In Utah, most construction is done atop clay and there is not much data on how earthquakes affect clay soils.

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E-mail: haddoc@desnews.com