The Pratt Truss Bridge: Originally Founded By Caleb And Thomas Pratt

A simple beam bridge that is flat across and supported at the two ends. A longer beam bridge can be held up along the middle by piers standing in the river. The weight of the bridge itself, plus the load that it carries, plus gravity are the downward forces are spread evenly across the length of the bridge. The upwards forces that hold the bridge up come from the piers. The Confederation Bridge in Canada is a famous beam bridge.

The first completed steel bridge was the Eads Bridge, in St. Louis Missouri. Steel was a very new material and was just starting to become commercially available. Steel was a smart choice to use because it is extremely hard and resists rusting. The Eads Bridge was the longest arch bridge in the world, of 510 feet long. St. Louis became a very important city in the midwest and had to really compete with Chicago during the Civil War. After the Civil War, St. Louis started growing in all directions. “.... the city of St. Louis wanted to reestablish its prewar dominance as the economic powerhouse of the midwest” (Ostrow 75). The main reason to build the Eads Bridge was to connect settlers from the East to the lands of the West. At the time there

In the small town of Waco, Texas who would have thought it was once well known for the structure of a bridge, the Waco Suspension Bridge to be exact. Up until 1870, the Brazos River was just a simple river that had no special meaning to it. The land around it was empty, occasionally you would find cattlemen pushing their cattle across stream, but that was only because you could not find one bridge that spanned the eight hundred miles of river flowing through Central Texas. This caused a serious transportation issue for merchants and travelers. It became clear that a better means of crossing the river was necessary.

I was merely walking to work when I thought I saw death. I never saw so much horror and disgust as I walked across the Edmund Pettus Bridge over the Alabama River on March 7, 1965. I was never a part of the march, I was going to work but as a black man that didn't matter.

Initially, suspension bridges before 1940 were made of piers, towers, wires, anchorages, and roadways. Piers were the main foundation for the suspension bridges. There usually were two of them, which were made out of cement and were entrenched in ground underneath the body of water that the bridge was spanned across. Towers were built on top of the piers to provide a means of connection for the roadways and wires. Wires were connected to the towers, roadways, and anchorages to provide tension support for the weight of the bridge. The anchorages were large cement platforms that were planted into the ground on either side of the land so that the wires could be connected to it. Lastly, the roadways were the main point of the suspension bridge. They usually were wide enough to provide four lanes of traffic and stretched from one side of the bridge to the other. This was the basic design of the suspension bridges

The Hannibal Bridge opened up many opportunities for Kansas City, turning from a small frontier town, into a generous city that outgrew all others in the region. Without railroads, Kansas City’s would eventually be at a great disadvantage due to the lack of north/south connection across the Missouri River. With congressional backing and the support of the Hannibal and St. Joseph, construction on Hannibal Bridge could begin. Engineer and bridge builder Octave Chanute, took over the project and when completed the bridge spanned an impressive quarter of a mile on seven piers sunk deep into the riverbed. Knowing the significance of this bridge, 40,000 people turned out for the festivities. The Hannibal Bridge helped connect Kansas City to Chicago

Each separate truss (of the dimensions 920x5x50mm) consisted of a Pratt truss with nine diagonal members on each side of the centre. The model was tested in sufficiently isolated condition by tutors. It successfully passed the initial weight test, and satisfactorily resisted horizontal forces. Once fitted onto the testing rig, loads were applied and increased incrementally. Slight deformation was observed before failing at 12.5 kg, at which force a collection of members failed in succession, concluding the test.

In the short story “An Occurrence at Owl Creek Bridge”, a man being killed is having an out of body experience while he is being hanged from the bridge (Bierce). He experiences himself escaping death, but in the end everything he was feeling was just himself dying, suspended from the bridge (Bierce). In his eyes, he experienced dying while staring into his wife’s eyes as he was about to embrace her, he was shot in the back of the neck (295). When in reality, all along, he was hanging by a rope from the bridge (295). His body died on the bridge, but his soul did not die until it stood in his yard staring at his wife (295).

Structurally, the bridge is a composition of two key metals steel (2 x 1011 Nm-2) and aluminum. These metals are common in bridges due to their properties of high strength and

Maintains clear detailed records of meetings and events that take place during the construction process.

Truss bridges have been around for a long time. I see truss bridges the most out of all the different types of bridges and to me it seems like the most popular type of bridge. In addition there are thirty different types of Truss bridges which means that there is a bigger variety of Truss Bridges instead of just having one type. Truss bridges have triangular shaped beams that go all across the bridge. The bridge also is above the roadway instead of under the roadway like the arch bridge. Truss bridges could also stretch very far. The longest cantilever Truss bridge that goes is called Crescent City Connection and it is 13,418 feet long with a width of 52 feet. There is also a really long Truss bridge that is near Hoboken, the name of the bridge

“Where are you Stephanie”, a voice called, bringing her back. The scene evaporated, no longer in a bedroom,

About eighty years ago, engineers were able to build a bridge on time and within budget with no problem; today, most of the projects take extra time and money to finish. What exactly happened between now and eighty years ago that caused such a drastic shift? It is clearly not the engineers nor the technology; in fact, those have only improved over time. Today, engineers are faced with much more than designing and building the infrastructure, as they were before. They compete with politicians for funds, fight for the safety of workers, and protect our environment by adhering to the numerous laws and acts set forth by the government. In the future, we can only expect more costs, longer time periods for projects, and an increase in costs and

It is shaped in a way to transfer weight to the towers and anchors with its tension (O'Connor, 1971, p. 372). Cables are made of high strength wires spirally bound to form a rope (O'Connor, 1971, p. 372). Vertical cable suspenders that are fastened to the main cables hang the actual roadway. Stiffening girders and trusses are along the side of the bridge to distribute concentrated loads and help to keep the motion of the bridge at a minimum (Troitsky, 1994, p115).

Superstructure bears the load that is being passed over the bridge and it transmits the forces caused by the same to substructure. Load received from the decking is transferred on to the substructure by Bearings. They also distribute the load evenly over the substructure material as it may not have sufficient strength to bear the superstructure load directly. Piers and Abutments are the vertical substructures which transfer the load to the earth in the foundation. Wing walls and returns are constructed as the extension of