Evaluation of Rigid Pavement Joint Seal Movement

The subject of sealing concrete pavement joints has been studied for many years, and a wealth of technology exists for successfully installing pavement joint seals. However, in practice, a great deal of inadequate performance has been observed by highway agencies in the United States in recent years. A primary reason for the observed problems is inadequate control of construction processes. Another very significant factor affecting the performance of joint seals is climatic conditions. Examined are the effects of climate on the movement of rigid pavement joints. Temperature, joint movement, and other data collected as a part of the Long-Term Pavement Performance (LTPP) program data collection for seasonal sites have been used to assess actual joint movements in various climatic conditions throughout the United States and Canada. These measured data are compared with theoretically calculated joint movements. In most cases the actual movements appear to be greater than those theoretically predicted. On the basis of measured joint openings from LTPP seasonal sections, the conclusion is made that the measured joint opening values are greater than joint opening values calculated using the AASHTO equation described below. The data also provide evidence that irregular joint openings are present at all the sites evaluated.