in the world for controlled laboratory testing in various
hydraulic environments,” said Paul Clopper, director of
applied technology in Ayres’ Fort Collins office. “It’s extremely
valuable to have this world-class hydraulic modeling
laboratory 15 minutes away from our office. It’s a huge
advantage to our clients to have us and CSU right in the same
town.”
Back in 1987, CSU and Ayres collaborated to create a
physical model of the Schoharie Creek Bridge near Fort
Hunter, New York, which collapsed in April 1987 due to bridge
scour. Ten people died in the collapse. “That catastrophe
really was the impetus for the nationwide scour assessment
program that FHWA administers,” Clopper said.
Ayres’ engineers, including Pete Lagasse and Jim Schall
– both of whom have doctorates in engineering from CSU –
worked with CSU hydraulic engineers to create a scale model
and analyze it in the CSU indoor flume.
“By demonstrating the method of scour by which this
bridge failed, we, as part of the National Transportation Safety
Board’s forensic investigation team, were able to identify
the probable cause of the failure for the NTSB’s investigation
report,” Lagasse said. The effort to repair, protect, or replace
all bridges with similar problems continues today, more than
30 years later.
Most recently, Clopper and Lagasse led an NCHRP research
project aimed at improving design criteria for environmentally
sensitive bank stabilization and protection measures. The
study compared “hard” engineered and “soft” vegetative
bank protection measures in a laboratory setting to mimic real
stream conditions. Small willow cuttings were grown for about
seven months in a 20,000-square-foot CSU greenhouse. Then
20-foot-long, 15-ton “planter trays” of willows were placed in
CSU’s research flume. In August and September 2014 water
was run through the flume – and over the willows – at high
flow rates (50, 100, and 150 cubic feet per second) to test
how well the willows protected the soil in which they were
rooted. These tests provided design guidance for the “soft”
erosion protection techniques that are preferred by many
environmental agencies.
Engineers and academics alike get their hands dirty –
literally – on these applied research projects.
“On the streambank project we were arm-deep in mud
figuring out the best way to do it,” said Chris Thornton,
director of the hydraulics lab. “The staff at Ayres wear boots
when they come to see us.”
Between five and 15 master’s degree students and 10 to
20 undergraduate students work at the lab at any given time.
The students build models, shovel rock, collect data, and
ultimately use the project information in their own research
reports.
“It’s invaluable for students,” Thornton said, “not only the
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