Thi s report describes the results of a preliminary evaluati on of the nature and extent of depressed transversed cracking of asphalt pavements in Oklahoma. The primary purpose of the Phase I study was to develop and evaluate procedures for collecting field data on a larger scale in Phase II. Four sites were selected using input from Division Maintenance Engineers for detailed evalua tion. Data such as crack occurrence and distribution, crack crosssection, pavement crosssection, general topography, general soils were collected and evaluated. The results of the Phase I evaluation indicate that:

1. Transverse cracking of asphalt pavements is a prevalent problem in North Central Oklahoma.
2. The depressionsassociated with transverse cracks occur because of a combination of factors, including, at a minimum; the type of subgrade, the stiffness of the asphalt, and the size and number of vehicles.
3. The field procedure is used to collect test section data, although time consuming, worked very well .