Increasing the Service Life of Bridge Decks by Incorporating Phase-Change Materials to Reduce Freeze-Thaw Cycles

During a freezing event, pore solution in cementitious bodies expands and creates stresses that can cause damage; therefore, reducing the number of freeze/thaw cycles experienced by a structure will extend the structure’s service life. The incorporation of phase-change materials (PCMs) to reduce the number of freeze/thaw cycles experienced by bridge decks has been investigated by modeling, mechanical testing, calorimetry, and X-ray microtomography. Models identified geographical regions in which freeze/thaw damage is not a significant concern and regions where this technology may be practical, increasing the service life of a bridge deck by at least 1 year. The incorporation of PCM reduces strength by varying amounts and for varying reasons, depending on which PCM is used and how it is introduced into the concrete. Because a variety of methods exist to address this loss in strength, PCM incorporation shows promise as a technique for addressing one aspect of worldwide infrastructure maintenance challenges.