performance of asphalt pavements in tehran

this paper identifies eleven types of asphalt pavement distress types, commonly occuring in tehran metropolitan area. of these, five distresses namely: corrugation; utility cut depression ;pot holes; alligator cracking; and loss of bridge deck surfacing are rather common. however, others namely: shear failure; shrinkage cracks; lane joint cracks; bleeding; and shoulder distress are less prevailing. also in this paper, the probable causes of these distresses are discussed, and proper methods of preventive, as well as, corrective maintenance are pointed out.