Long-Time Observations of Contracfion Joint Opening in Concrete Pavements Measurement and Evaluation

Long-time measurements of contraction joint opening were performed during a 25-year period for several pavement systems [concrete full depth construction, concrete pavement on a temperature insulated, cement treated (CTS) and bituminous subbase]. The data obtained were analyzed and the mean opening of the joints, the standard deviation, the coefficient of variance, the asymmetry and the excess of the openings were plotted independent of the temperature in the middle of the concrete pavement. The diagrams show that at the same temperature the opening increased with time in all pavements. Omitting the expansion joints, which has been customary in Germany since the 70ies,and bonding between the concrete and the CTS result in a good long-time performance.