Natchez Trace Bridge, Franklin, Tennessee
The Natchez Trace was a 440-mile-long path extending from Natchez, Mississippi to Nashville, Tennessee, linking the Cumberland, the Tennessee and Mississippi rivers. It was used extensively by Native Americans and early Caucasian explorers as both a trade and transit route in the late 1700s and early 1800s. Today, the trail has been commemorated with the 444-mile-long Natchez Trace Parkway which follows the trail's approximate path. (Wikipedia)
One of the most revolutionary arch bridges in recent years is the Natchez Trace Bridge in Franklin, Tennessee, which was opened to traffic in 1994. It's the first American arch bridge to be constructed from segments of pre-cast concrete, a highly economical material. Two graceful arches support the roadway above. Usually arch bridges employ vertical supports called "spandrels" to distribute the weight of the roadway to the arch below, but the Natchez Trace Bridge was designed without spandrels to create a more open and aesthetically pleasing appearance. As a result, most of the live load is resting on the crowns of the two arches, which have been slightly flattened to better carry it. Already the winner of many awards, the bridge is expected to influence bridge design for years to come. (PBS Nova)
Natchez Trace Bridge, Franklin, Tennessee
The Natchez Trace was a 440-mile-long path extending from Natchez, Mississippi to Nashville, Tennessee, linking the Cumberland, the Tennessee and Mississippi rivers. It was used extensively by Native Americans and early Caucasian explorers as both a trade and transit route in the late 1700s and early 1800s. Today, the trail has been commemorated with the 444-mile-long Natchez Trace Parkway which follows the trail's approximate path. (Wikipedia)
One of the most revolutionary arch bridges in recent years is the Natchez Trace Bridge in Franklin, Tennessee, which was opened to traffic in 1994. It's the first American arch bridge to be constructed from segments of pre-cast concrete, a highly economical material. Two graceful arches support the roadway above. Usually arch bridges employ vertical supports called "spandrels" to distribute the weight of the roadway to the arch below, but the Natchez Trace Bridge was designed without spandrels to create a more open and aesthetically pleasing appearance. As a result, most of the live load is resting on the crowns of the two arches, which have been slightly flattened to better carry it. Already the winner of many awards, the bridge is expected to influence bridge design for years to come. (PBS Nova)