Paved roads as we know them did not exist prior to the twentieth century. While some roads, primarily freeways, have concrete surfaces, the majority of road paving in the United States is done with asphalt. Asphalt Houston consists primarily of tar from crude oil mixed with sand and gravel, called aggregate, to form a very strong bond. This strength is the main reason that 96% of all modern roadways are covered with this black, sticky material.
The first records we have of paved road surfaces are in the Babylonian civilization, where some highways were covered with large stones. Thousands of years later, some early British highways employed timber as a short-lived surfacing material. Sand, gravel, and water formed most roadway surfacing materials until the beginnings of the twentieth century, when the automobile made the creation of better highway surfaces a necessity, not a luxury.
Modern highway construction was given a boost through the efforts of two Scottish engineers named Telford and McAdam. They both worked on modern highway prototypes, and were the first to actually create drainage in raised roadways, in addition to making adjustments for traffic, sloping and highway alignment. When covered with tightly laid stones, the hard surface was vastly superior. From McAdam came the word macadam, a word still in wide use today.
The product is a mixture of substances left over from fuel refining, primarily bitumen. A component of crude oil, bitumen is a very thick liquid. When mixed with the proper amount of sand and gravel, however, it dries quickly and strongly, eliminating long road-repair delays. In addition to road surfacing, this product is used in a number of other applications, including roofing shingles.
Blacktop not only saves money in the manufacturing process, but also in finished projects. Because it is so easy to use, and quick to be laid down, the costs saved in labor alone are enough to recommend it. As a surface, it offers superior skid resistance, and resists hard-to-see-through back-splashes from large trucks during wet weather. Because of its dark color, it gathers heat for melting a snow cover more quickly than concrete, and stamped road directions are easily marked and seen.
There are some issues, however. During construction, the unmistakable sulfur smell travels far and wide, and if breathed closely for long periods may be harmful to workers. In addition, traffic including large numbers of trucks and other heavy vehicles may cause rapid wear-down. Concrete roadways do not form potholes as quickly, especially in very cold regions where constant freezing and melting wreaks highway havoc.
Advantages outweigh problems, however. This is the only road surfacing material that enjoys an 80% recycling rate. The old asphalt Houston can be easily deconstructed with a bulldozer, and sent to plants where it can be remelted, and then remixed and reapplied. Even though it is originally made from crude oil, there is none of the wastage common in burned fossil fuels. It actually is part of the solution to our landfill and waste disposal issues.
asphalt Houston
The first records we have of paved road surfaces are in the Babylonian civilization, where some highways were covered with large stones. Thousands of years later, some early British highways employed timber as a short-lived surfacing material. Sand, gravel, and water formed most roadway surfacing materials until the beginnings of the twentieth century, when the automobile made the creation of better highway surfaces a necessity, not a luxury.
Modern highway construction was given a boost through the efforts of two Scottish engineers named Telford and McAdam. They both worked on modern highway prototypes, and were the first to actually create drainage in raised roadways, in addition to making adjustments for traffic, sloping and highway alignment. When covered with tightly laid stones, the hard surface was vastly superior. From McAdam came the word macadam, a word still in wide use today.
The product is a mixture of substances left over from fuel refining, primarily bitumen. A component of crude oil, bitumen is a very thick liquid. When mixed with the proper amount of sand and gravel, however, it dries quickly and strongly, eliminating long road-repair delays. In addition to road surfacing, this product is used in a number of other applications, including roofing shingles.
Blacktop not only saves money in the manufacturing process, but also in finished projects. Because it is so easy to use, and quick to be laid down, the costs saved in labor alone are enough to recommend it. As a surface, it offers superior skid resistance, and resists hard-to-see-through back-splashes from large trucks during wet weather. Because of its dark color, it gathers heat for melting a snow cover more quickly than concrete, and stamped road directions are easily marked and seen.
There are some issues, however. During construction, the unmistakable sulfur smell travels far and wide, and if breathed closely for long periods may be harmful to workers. In addition, traffic including large numbers of trucks and other heavy vehicles may cause rapid wear-down. Concrete roadways do not form potholes as quickly, especially in very cold regions where constant freezing and melting wreaks highway havoc.
Advantages outweigh problems, however. This is the only road surfacing material that enjoys an 80% recycling rate. The old asphalt Houston can be easily deconstructed with a bulldozer, and sent to plants where it can be remelted, and then remixed and reapplied. Even though it is originally made from crude oil, there is none of the wastage common in burned fossil fuels. It actually is part of the solution to our landfill and waste disposal issues.
asphalt Houston
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