Frost laws and seasonal weight restrictions
It stands to reason that hauling over-sized freight becomes more complicated in the winter months. Treacherous road conditions and large heavy loads do not equal a formula for easy transport. However, hauling heavy loads in the spring can actually cause more damage to roadways than hauling them in the winter. Many U.S. states and Canadian provinces have enacted “Frost Laws” or “Seasonal Weight Restrictions” to protect their roadways.
In geographic areas that experience below freezing temperatures during the winter as we do here in New Jersey, the potential damage to roads becomes greater as the temperatures rise, and the roads begin to thaw. Prior to freezing, water seeps into cracks in the pavement. As the water freezes, its volume expands. As the water that has seeped into the cracks in the pavement freezes, it expands and makes the cracks bigger weakening the surrounding pavement. As the springtime thaw intensifies, the ice inside of the various layers of the roadway melts and the void left behind leads to significantly weakened parts of the road itself.
Most major roadways are supported by a base layer with a sub-base layer under that. Then between four to six inches of pavement are laid on top of the base layers. On some highways, the total measurement of the three layers combined can be as much as three feet. During the thawing period, if trailer axles are overloaded, the layers of the roadway can compress and cause the road to bend and become deformed.
Roads are engineered to tolerate a certain level of axle weight. Numerous factors are involved in the calculation, including a “normal” level of residual moisture in the roadbed itself. That factor goes up during the thaw, and restrictions are put in place due to the weakened state of the road because of the excess moisture. As the moisture completely thaws and drains away, the road returns to its engineered level of strength and stability, and the restrictions can be lifted.
It is essential to be aware of frost laws and seasonal weight restrictions when planning to haul an over-sized load. Routes need to be carefully planned and sometimes altered, in order to be compliant with these seasonal mandates. Certain loads may need to wait until after the seasonal restrictions are lifted to be safely and legally moved. De Mase Trucking and Rigging has over 45 years of experience in hauling over-sized loads. Don’t hesitate to consult with us and put our expertise to use in planning your heavy haul.
Be sure to watch for our upcoming blog where we will go into more detail regarding seasonal weight restrictions in various geographical areas.
