Field Evaluation of Damages from Super Heavy Load Moves

Abstract

The number of superheavy load permits in the last five years has increased by a factor of 13.3. With continued economic development in Texas, superheavy load permits are expected to continue to increase. Significant efforts have been made to monitor, evaluate, and analyze pavement damage caused by the superheavy load moves. This paper documented six cases of pavement surface damage as the result of superheavy load moves. It was found that superheavy loads can cause serious damages to fresh seal coats if not properly routed. Based on these six case histories, it was concluded that seal coats are most vulnerable to damage under one or more of the following factors: (1) time after placement (the first 5 weeks are critical), (2) high temperatures, and (3) steep grades in combination with too few drive axles. The results indicate that even after repairs, the pavement condition is not as good as the original undamaged condition, as the damages are still visible approximately six years after repairs. The findings and lessons learned from these six cases can be used by other transportation authorities to improve their regulations and permitting procedures so that damage caused by superheavy load moves is minimized.