National Concrete Pavement Technology Center

Project description

The failure of concrete pavement as a result of pavement growth has become a serious concern as it causes blow-up distress and damages the adjoining structures, such as bridge abutments and decks. This further adversely impacts the road user, and the roads thus require costly maintenance and reparations. Pavement growth is caused by pressure generated from rising temperature and moisture content in the concrete pavement. The trigger temperature for pavement growth (TTPG) is the temperature at which all transverse cracks and contraction joints between the expansion joints begin contracting and generating an axial compressive force in the pavement section. This is a critical factor affecting pavement growth. However, the evaluation of TTPG has not been documented yet. TTPG is affected by the accumulation of concrete slab expansion resulting from the alkali-silica reaction, amount of incompressible material infiltrated in the joint or cracking. The rate of this accumulation depends on the environmental conditions, pavement age, pavement configuration, and pavement materials. Therefore, this study examines the factors affecting TTPG of in-service pavements, using the Long-Term Pavement Performance Seasonal Monitoring Program database. According to the results, TTPG is significantly affected by pavement age, precipitation, and joint spacing. The paper further presents an empirical equation to estimate the TTPG of concrete pavement under the given conditions based on the generalized linear modeling regression method.