MSU and MDT Develop Specialized Concrete
Montana State University and Montana Department of Transportation are collaborating in the development of a specialized concrete that is 20 times stronger than regular concrete. It will be used for the first time this summer to form parts of two 60-foot long bridges over Trail Creek near Wisdom.
MSU has been developing this unique concrete for over five years. It is special because it can carry up to 20,000 pounds per square inch.
Due to a specialized mixture that includes conventional concrete materials in addition to steel fibers, fly ash — a byproduct of coal-fired power plants — and chemicals that reduce the amount of added water, the material is roughly five times stronger than normal concrete, according to Mike Berry, associate professor in the Department of Civil Engineering in MSU’s Norm Asbjornson College of Engineering. It also cures rapidly, potentially reducing construction time, and resists corrosion, which will extend the lifetime of the structure, he said.
“It’s like normal concrete on steroids,” said Berry, who is leading the MSU research project. “If we could make all our bridges out of this stuff, it would be magnificent.”
The concrete is not new, Berry added, but until now its use has been limited due to high costs charged by companies that treat the mixture as proprietary, meaning only they can install it. The concrete developed at MSU uses the same principles but is non-proprietary and is designed to use locally available materials to further reduce costs.
According to Lenci Kappes, innovations and complex structures engineer in MDT’s bridge bureau, the MSU project could potentially cut the cost of the material in half. That would mean significant savings for the state not only with construction costs but also with reduced long-term maintenance due to the material’s durability.
The future cost savings are anticipated as MDT and contractors become more familiar with procuring, mixing and installing the material with MSU’s support, according to Kappes.
The MSU collaboration with MDT is part of a federal initiative to encourage states to adopt ultra-high performance concrete, according to Berry. Montana isn’t alone in its efforts, but “you can count on one hand the number of states that have actually developed and used this material, so we’re kind of unique in that way.”
According to Kappes, Montana has lots of bridges in need of replacement or repair, so the money-saving MSU mixture is a particularly relevant material coming at an opportune time. “This is really a learning experience,” he said. “We’re excited to take what we learn and apply it around the state.”