Transverse cracks in continuously reinforced concrete (crc) pavements have various shapes in the field. The randomness of a crack increases the probability of the formation of secondary cracks and consequently increases the possibility of punchouts and y-cracks, whichare the major form of distress in crc pavements. If the factors affecting the randomness of cracks can be identified and controlled, the pavement life will be increased. So far insufficient attention hasbeen given to the shapes of cracks in concrete pavement design and construction. As a first step toward the study of randomness, a methodology for objectively quantifying the degree of randomness of the crack was developed. The concept for a randomness index, to be used as a tool to represent the degree of randomness, is introduced. The technique used in the derivation of present serviceability index (psi) was used in developing the randomness index. An example of the application of the randomness index to an experimental study is also presented. It was found from the experimental study that the construction season, coarse aggregate type, and time of crack occurrence significantly affect the randomness of cracks. This paper appears in transportation research record no. 1307, Pavement analysis, design, rehabilitation, and environmental factors 1991.
Samenvatting