Asphalt in the US
Laura Ingalls Wilder, author of the beloved Little House on the Prairie,
tells of her first encounter with an asphalt pavement. She was on a wagon journey with her parents in 1894 that took
them through Topeka.
"In the very midst of the city, the ground was covered by some dark stuff that silenced all the wheels
and muffled the sound of hoofs. It was like tar, but Papa was sure it was not tar, and it was something like rubber,
but it could not be rubber because rubber cost too much. We saw ladies all in silks and carrying ruffled parasols, walking
with their escorts across the street. Their heels dented the street, and while we watched, these dents slowly filled
up and smoothed themselves out. It was as if that stuff were alive. It was like magic."
Today asphalt concrete, normally known simply as asphalt
or AC comes from the processing of crude oils. The word asphalt comes from the Greek "asphaltos,"
meaning "secure". Everything that is valuable in crude oil is first removed and
put to good use. Then what remains is made into asphalt cement for pavement.
Asphalt consists of asphalt binder and mineral aggregate mixed together then laid down in layers and compacted.
This dark, resilient material covers
more than 94 percent of the paved roads in the United States; it’s the popular choice for driveways, parking lots, airport
runways, racetracks, and other applications where a smooth, durable driving surface is required. Called at various times
asphalt pavement, blacktop, tarmac, macadam, plant mix, asphalt concrete, or bituminous concrete, asphalt pavements have played
an important role in changing the landscape and the history of the U.S. since the late 19th century.
~ National Asphalt Pavement Association