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KALAMAZOO, Mich.—A sure sign of spring is road construction. While some may dread the interruptions to their daily commute, researchers at ɫɫ�� Michigan University are helping to pave the way for ensuring the durability of Michigan bridge surfaces, minimizing disruptions and improving construction timelines.

Dr. Upul Attanayake, professor of civil and construction engineering and director of ɫɫ��’s MDOT Center of Excellence for Structural Durability, led a team from the College of Engineering and Applied Sciences that is working to determine the minimum timeline for applying epoxy overlays and protective sealers to new concrete on the surface of Michigan bridges. Attanayake’s team showed the timeline requires just 21 days not the 28 days required by policy.

“This process—applying the overlays at day 21 of curing—offers significant savings from project and road user costs without compromising concrete durability and overlay/healer sealer performance,” says Attanayake.

Attanayake’s team set out to test the performance of healer sealers at 21 days by evaluating the effectiveness of sealed cracks in preventing chloride ingress—one of the leading causes of deterioration of concrete road surfaces. The bond of the epoxy overlays and healer sealers on standard bridge deck joint repair and Grade DM concrete mix was assessed primarily by conducting a direct pull-off bond strength. The overlay performance was evaluated under standard laboratory conditions, simulated summer exposure conditions, wet and dry conditions, and the outdoor conditions representing southwest Michigan exposure; outdoor conditions were evaluated during fall, winter and summer. 

“We supported our findings by collecting overlay bond strength data over patches and repairs with new concrete on two in-service bridge decks, and healer sealer depth of penetration and bonding of concrete in an in-service bridge deck with extensive cracking,” says Attanayake.  “Basically, all that is left is to get the revised policy approved and implemented by MDOT to allow contractors to finish their work early to minimize traffic disruption on our roads.”

The study was completed in partnership with the Michigan Department of Transportation and the Tourney Consulting Group, LLC. MDOT funded the research.

The project included an extensive laboratory and field testing and provided research opportunities for 15 graduate and undergraduate students, including Naveen Ranasinghe, a mechanical and aerospace engineering major from Sri Lanka.

“As part of the team, I helped design and fabricate a mechanical drive system to simulate highway loading to evaluate the performance and service life of overlays. I am so glad that ɫɫ�� provided this opportunity to apply my knowledge and skills to develop an equipment from scratch to evaluate the life-cycle performance of highway materials,” says Ranasinghe, who plans to graduate in fall 2024.

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