As the Minnesota Department of Transportation (MnDOT) continues to pursue building thinner concrete pavements, the design and performance of the pavement can change: One such feature is sawing the concrete into 6’ by 6’ panels and eliminating the dowel bars, which has caused some faulting of the smaller panels. Through MnROAD (Minnesota’s Cold Weather Pavement Testing Facility) and National Road Research Alliance (NRRA) solution, the MnDOT has been testing the addition of macrosynthetic fibers to the thin concrete pavement.
Previous research at MnROAD has shown that fiber-reinforced concrete pavement contraction joints at MnROAD were not cracking (“activating”) as frequently as non-fiber reinforced concrete:
Joint Sealant Testing at MnROAD:
MnROAD hosted the “Louisiana Multi-Functional Materials Group LLC” the week of June 24, 2019 to install their innovative concrete joint seals. The video shows them installing their shape memory polymer-based seal, designed to react thermally opposite to common physics.
• When the concrete heats up, the seal contracts to prevent it from squeezing out of the channel.
• When the concrete freezes, the properties of the polymer seal allow it to relax and fill the joint.
Guoqiang Li, Professor-Louisiana State University, and his team installed this at MnROAD to test the seal’s behavior in a cold climate. Similar trial installations of the material are occurring in Louisiana. To compare performance, the MnROAD team installed several control joint sealants.
MnROAD researchers will monitor the performance of the sealant for 2 years under a research partnership agreement partially funded by the National Science Foundation.
For the ISCP June 2019 posted VIDEO affiliated with this article titled “VIDEO: Testing Joint Seals at MnROAD”, please go to: https://www.concretepavements.org/2019/06/28/video-testing-joint-seals-at-mnroad/ (or click on the adjacent video on the ISCP Home Page: www.concretepavements.org)
For the description of the study, please go to: http://www.dot.state.mn.us/mnroad/nrra/newsletter/currentissue.html?utm_content=&utm_medium=email&utm_name=&utm_source=govdelivery&utm_term=#joint