School of PE Blog

Construction on roadways is almost impossible to avoid, especially when traveling more than a few hours. Although some may find running across an orange construction zone sign irritating, roadwork is extremely important for not only your car's maintenance but your safety too. Driving over a bumpy road or driving over a deep pothole can cause wear on tires and can even cause steering difficulties and car accidents.i Without proper pavement construction and maintenance performed by professional civil transportation engineers, roadways we drive on every day would be extremely dangerous to travel on. Ensuring that pavement is durable and can withstand various factors, such as weight and weather conditions, will yield safer travels for drivers.

When evaluating pavement performance, there are many factors that can affect the longevity of the pavement. Below are three of the top variables that will determine how durable the pavement can remain for a set amount of time.

1. Traffic Load

Out of all of the variables that could affect pavement performance, traffic is the top influencer. Configuration, loading magnitude, and the amount of load repetition via heavy vehicles has a large impact on pavement durability. According to an article published in the Journal of Mechanical and Civil Engineering, "The damage caused per pass to a pavement by an axel is defined relative to the damage per pass of a standard axle load, which is defined as a 80 kN single axle load (E80). Thus a pavement is designed to withstand a certain amount of standard axle load repetitions (E80's) that will result in a certain terminal condition of deterioration."ⁱ

2. Subgrade Quality

The subgrade is known as the soil that withstands the weight of the applied wheel loads. A weak subgrade will cause immense flexing of the pavement, which can lead to various issues such as cracking and surface deformation. Addressing the natural variations of the subgrade prior to laying pavement down will yield positive impacts on overall pavement performance and life span. The subgrade quality can also be affected by moisture when moisture seeps into the subgrade laterally. "The result of moisture ingress is the lubrication of particles, loss of particle interlock and subsequent particle displacement resulting in pavement failure."ⁱⁱ

3. Quality of Construction

Original construction and the quality of periodic maintenance work can improve pavement longevity. During construction work, layer thickness, moisture conditions, and compaction analysis must be carried out to ensure overall high pavement quality. If these factors are not put into consideration when performing construction or maintenance, then pavement quality will decrease and may yield disintegration or surface defects.

The above factors of pavement durability are extremely important to consider when performing pavement work. Without professional civil transportation engineers, our roadways would be lacking in overall safety. Since road safety and pavement durability is extremely important, School of PE offers an 84-hour PE Civil exam review course to assist future civil transportation engineers prepare for their licensing exam.

If you want to prepare for the PE Civil transportation exam and make a big impact in the world of roadway safety, sign up for School of PE's PE Civil exam review course today!

References

i Top 25 Causes of Car Accidents. Retrieved from
https://seriousaccidents.com/legal-advice/top-causes-of-car-accidents/

ii Adlinge, S., & Gupta, A. Pavement Deterioration and its Causes. Retrieved from https://www.iosrjournals.org/iosr-jmce/papers/sicete(civil)-volume6/60.pdf