KINDA BORING, BUT WORTH KNOWING DEPT.
Drivers put up with flats, damage to their vehicles and even crashes due to our many-potholed roads, but it’s not just a local phenomenon. From 1995 to 2005, the weight load on urban highways increased by half due to the increased weight of trucks on our streets and highways, according to Federal Highway Administration statistics.
Our bridges are also feeling the strain; a 2006 study by the Department of Transportation Inspector General of 43 bridges in Massachusetts, New York and Texas found that at least 12 of them allowed vehicles to cross that were heavier than the bridge’s maximum weight limit. 11 of those did not have the required posting signs. Some engineering experts speculate that the wear and tear over the years of heavier loads could be one of the factors that triggered the collapse of the interstate bridge in Minneapolis August 1.
“More weight wouldn’t be a problem if the highway system was regularly and adequately maintained because well-kept roads and bridges can handle the added weight,” says University of Texas civil engineer professor C. Michael Walton. The maximum amount of truck weight New York City roads allow is 73,280.
Clayton Boyce, a spokesman for the American Trucking Association, said it is unfair to single out trucks. “Yes, (the deterioration is due to) an increase in traffic and an increase in cumulative truck weight, but there has been a similar increase in the number of automobiles,” Boyce said.
Mark Berndt, chairman of the truck weight committee for the National Academies of Sciences’ Transportation Research Board, said the United States has some of the strictest weight limits of any industrialized nations, limiting trucks on the federal interstate system to 80,000 pounds, a limit that has been around for decades. State roads, however, can allow heavier trucks. Trucks in Europe can go up to 97,000 pounds and Canada and Mexico allow up to 100,000 pounds, he said.
“There’s no doubt that the truck has more of an impact on a bridge than a car, but it’s really being driven by the nature of our economy,” said Berndt. “Certainly truck traffic has increased far more than anyone predicted. That’s been one of the big issues in transportation in the last 10 to 15 years. Berndt also said farmers who used to drive small trucks are now using bigger and heavier tractor trailers in rural areas. – Josh Max, AutoGigolo