Project Details
RESEARCHERS
Shreenath Rao, Hesham Abdualla, Hyung Lee, Michael Darter
SPONSORS
Wisconsin Department of Transportation
KEYWORDS
Buckling, Concrete pavements, Field tests, Literature reviews, Pavement joints, Thermal expansion
Project description
Buckling of concrete pavements is a serious problem in many states, but even more so in Wisconsin due to a combination of factors including climate, construction practices, maintenance practices, materials, and design. Although the incidences of buckling in concrete are fewer than other distresses such as cracking and spalling, they disproportionately affect the traveling public due to potential safety concerns requiring immediate repair, which is expensive and can be difficult. The research team investigated buckling in Wisconsin by conducting a thorough literature review, interviewing agency and industry representatives from other states and countries, reviewing neighboring agency standards and specifications, performing field investigations of eight buckling sites and three control sites in Wisconsin, analyzing the field data, and simulating the risk of buckling using analytical modeling. Based on the research activities, the research team noted factors that increase the risk of buckling and provided recommendations to reduce the occurrences of buckling in Wisconsin. Specific recommendations include considering single cut sawed joints filled with low modulus sealant to reduce amount of incompressibles and water infiltrating through the joints, reviewing and making changes to cold weather concreting practices to reduce likelihood of low neutral temperature thus effectively increasing the concrete temperature at which buckling happens, specifying strong and more durable concrete to increase concrete’s resistance to compressive stresses, using concrete with lower coefficient of thermal expansion when possible to reduce expansion and associated compressive stresses, repairing spalled joints with concrete full- or partial depth patches as soon as practical to improve joint integrity, providing positive drainage in areas susceptible to moisture to reduce concrete damage, using a stabilized base course to increase friction and reduce compressive stresses, and using wider paved shoulders and vegetation beyond shoulders to help reduce the availability of incompressibles to the mainline joint and crack. Wisconsin Department of Transportation should also experiment with forcing joints to activate to reduce the number of dominant joints and consider using pressure relief expansion joints as a last resort when other options have been exhausted.