ISU engineering teams with Idaho Transportation Department on testing low-cost, high-quality concrete used for bridge construction
August 10, 2018
POCATELLO – Idaho State University civil engineers and the Idaho Transportation Department (ITD) are teaming up on the second phase of testing of a new type of concrete material that will be installed between girders on a Highway 36 bridge over the Bear River near Preston.
The ITD has given ISU civil engineering Professors Arya Ebrahimpour and Mustafa Mashal additional funding to test a type of concrete material for connecting bridge precast concrete girders that may cost less the a tenth as much as current materials being used.
“We’re going from small-scale testing in the laboratory to full-scale testing in the field,” Ebrahimpour said. “The new material worked well in the laboratory, but that can be different than what happens in real life.”
This new type of high-early strength concrete with polypropylene fibers could be a cost-effective alternative to connect precast bridge deck elements in what is called Accelerated Bridge Construction, a relatively new method in the United States and Idaho.
Currently, Ultra High Performance Concrete (UHPC) is used for Accelerated Bridge Construction but it is expensive, costing up to $15,000 per cubic yard installed in Idaho for ITD. The new concrete ISU is helping test costs about $600 per cubic yard installed. The estimated cost savings of using the new material for one bridge project is approximately $100,000.
The new, less expensive concrete tested has less strength than UHPC, but likely has adequate strength for field-cast connection of precast bridge girders. It will also be tested to see how good of bond it has with existing concrete.
“We are instrumenting the bridge with about 90 sensors and will be collecting data under heavy commercial trucks passing over the bridge,” Ebrahimpour said.
ISU civil and environmental engineering master’s graduate students Maximilian Casanova, from Los Angeles, and Utsa Rashique, from Bangladesh, worked on the first phase of the project, and Christopher Clauson, from North Dakota, worked on the second phase.
ISU has been working with ITD Bridge Section in Boise and District 5 in Pocatello.