Is It Cement or Concrete? What is the Difference?

The terms ”concrete” and “cement” often seem interchangeable and when used to identify pavement type it can be confusing. There are both asphalt cement and asphalt concrete, and Portland cement and Portland cement concrete. Cement refers to the binding material used to “glue” the rock or aggregate together. The right […]

Selecting The Right Pavement Type

Selecting a pavement surface is typically a choice between asphalt concrete or Portland cement concrete. In many parts of the country, AC is the first choice. In the South, PCC is more common. Pavement type selection has many factors: The primary factor is initial cost of installation. Local material cost […]

Tearing Up the Highway Like a Big Old Dinosaur

If you know me, you know I’ll take any opportunity to work a Bruce lyric into a post. But, unlike the song, a Cadillac isn’t tearing up the highway. The machine used is called a rotomill. In the photograph, it is working overnight to remove a portion of a parking lot asphalt concrete […]

The First Smart Road?

Roads have been constructed for centuries, but have intelligent roads been around for as long? A good case can be made by examining the above photograph. The roadway is found in the ancient Roman city of Pompeii.  The Romans were on to something here and you will see similar approaches used in […]

The 2,000-Year-Old Road

It has been noted that ancient Roman roads are still intact after 2,000 years but nowadays, it seems our roads are in constant need of repair. Why is that? There are many reasons for short performance lives, but for now, we will focus on the Roman road cross section.  After comparing […]

Pavements Keep Us Out of the Mud

My favorite graduate school professor, Marshall Thompson, PhD, professor emeritus at the University of Illinois, had a folksy way of boiling down engineering concepts to the basics. “Pavements keeps us out of the mud.”   During a typical lunchtime, I would sit in the reception area of Talbot Laboratory, reading […]

The Old Plank Road

Throughout history, roads have been built with local materials. The Romans used mountain and volcanic rock quarried into slabs. Gravel and cobbles were used for early roads in the United States. Where available, thick oil was poured over compacted aggregate to produce an all-weather Macadam road. For a large portion of […]