HIGHWAY ROAD DAMAGE: CAN BIG WHEELS KEEP ON ROLLING?

This article, which considers the question, can our pavements handle heavy truck loadings? reviews the history of pavement design, and answers yes to the question. It is noted that an increase in the average weight of trucks by 20 percent can cut the expected life of a concrete pavement in half. However, it is pointed out (according to the AASHTO Design Guide), that an increase of 1 additional inch of concrete pavement thickness will double the load carrying capacity of the pavement. The cost of providing this additional inch of concrete at the initial construction stage is much lower than the cost of future rehabilitation of the roadway under traffic conditions. There is a need to think of the total life cycle of the highway rather than seek the lowest possible initial cost. It is also suggested that truck lanes separate from the rest of Interstate traffic lanes but running parallel to them may be in the best overall public interest.