One of the simplest things to take for granted when traveling is the concrete beneath the tires. Throughout the last century, concrete has played a major role in the United States’ transportation systems, from creating new roads to repairing existing highways. The country’s highway system, including its nearly-45,000-mile interstate system, carries about 40 percent of total traffic. This figure includes 90 percent of tourist traffic and 70 percent of commercial traffic. Pairing concrete preparation with construction drying solutions is crucial to the nation’s transit infrastructure as it improves a road’s safety and minimizes disruptions to traffic.
The Benefits of Concrete Drying
While many roads and highways use asphalt, approximately 60 percent of the interstate system is concrete, particularly in urban areas. The reason: Concrete is more durable. With proper concrete drying, the material offers additional advantages, including:
- Concrete supports heavy loads
- Concrete experiences less deformation than asphalt in spite of heavy loads
- Concrete is a cost-effective alternative for new construction and maintenance
- Concrete usually lasts twice as long as asphalt, up to 30 years without the need for major repairs or resurfacing; asphalt lasts up to 12 years
How Concrete Keeps America Connected
Modern Vehicles Give Rise to Modern Roads
The history of concrete highways in the U.S. began with a 9-foot wide, 24-mile long, 5-inch thick strip of pavement constructed near Pine Bluff, Arkansas, in 1913—five years after Ford introduced its Model T. A year after the construction of the first U.S. highway, contractors used cement to pave 2,348 miles of roadway. In 1916, President Woodrow Wilson signed the Federal-Aid Highway Act, directing the federal government to assist the states with road construction.
Oregon became the first state to implement a fuel tax on gasoline to fund road construction in 1919. Other states soon followed suit. As a result, fuel taxes became—and still remain—the primary means of funding road maintenance and construction.
Using Concrete to Advance American Infrastructure
During the 1930s and 1940s, technical advances and design developments made paving roads with concrete faster, more durable and less expensive. Before these advancements, roads were about 6 inches thick in the middle and up to 9 inches thick along the edges. The developments allowed contractors to build roads with a uniform depth, saving money and time because concrete drying did not take as long.
In the late 1930s, roads began experiencing increased pumping, a phenomenon in which concrete slabs lose support and crack when the wet soil particles and clay under them shift due to increased heavy truck traffic. To solve this problem, contractors constructed roads with sub-bases made of gravel, slag or crushed stone. By the 1940s, some highways used soil-cement sub-grades. Around this time, contractors also developed a new technique to make pavement joints. They sawed the concrete after it partially hardened, rather than lump the cement up to either side of the joint when it was still fully plastic. The change made road surfaces more even.
During the 1940s, transportation specialists learned that concrete preparation that included the introduction of tiny air bubbles into the aggregate mixture reduced scaling, or peeling, on road surfaces that resulted from freeze-thaw cycles and deicing salts. This discovery led to the creation of air-entrained concrete, which many roads in the U.S. use.
Highway construction in the country boomed during the 1960s and 1970s, when contractors built thousands of miles of roads. Concrete-related innovations over the last several decades have made it possible for contractors to resurface and rehabilitate highways with minimal interruptions. Today’s fast-track concrete is ready for commuters in 12 or fewer hours because of its lower water content, which improves its strength and reduces salt permeability. The addition of steel bars in slab joints extended the life of concrete highways by up to 15 years.
As concrete continues to advance, contractors will continue to rely on construction drying solutions to ensure the proper drying and curing of road surfaces. Polygon’s custom drying solutions help prevent project delays and ensure that concrete, whether it’s on a road or a warehouse floor, is durable and acts reliably. Get in touch with a specialist at Polygon to learn more.