The major considerations in the evaluation of a slab's condition, where surface defects exist, are the number of defects, their type and size. It is possible for a slab to contain a large number of surface intrusions without being appreciably damaged, if the impairments are all very small. On the other hand, only a few very large defects would be very damaging. Certainly, the most satisfactory condition would be the complete absence of blemishes.

In the surveys which have been made since the beginning of these pavement investigations, soil holes, chert pop-outs, shale pitting, trash imbedments and cracks have comprised nearly one hundred percent of the defects observed. The defects are listed in declining order of damaging effect to the slabs inspected. By far, the most prevalent types of defects are soil holes and chert pop-outs. These surveys have been made, insofar as possible, to include all defects which were one-half inch or more in diameter and all transverse cracks.

Report Date


Report Number

No. 169a

Digital Object Identifier