Bridge_project

=
__**Purpose of the bridge:**__ The purpose of the Brooklyn Bridge is connecting the New York City of Manhattan and Brooklyn. =====

=
__**Type of bridge:**__ Because of its design, the Brooklyn Bridge is considered as a Suspension Bridge. In fact, when its construction ended, it was the largest suspension bridge in the world and the first steel-wire suspension bridge. =====

=
__**Materials:**__ The Brooklyn Bridge was designated a National Historic Landmark by the federal government and a National Historic Civil Engineering Landmark by the American Society of Civil Engineers. In recent decades, the landmark structure has been refurbished to handle the traffic demands during its second century. The bridge, which now accommodates six lanes of automobile traffic, carries approximately 145.000 vehicles per day (AADT). After nearly 120 years, the bridge still has the 44th longest main span among the world’s suspension bridges. The deck is made of steel meshing, which is filled with concrete to make it stronger. Part of the concrete has been disintegrating, causing the bridge deck to weaken. Engineers retrofitted the existing trapezoidal trusses with six steel arches founded into the original masonry abutments. =====

=
__**Technology involved in its construction**__: Before the Brooklyn Bridge, the individual wires that make up the rope were made from iron. Building the Brooklyn Bridge not only required designing the bridge, but also inventing key materials. In the 1840's John Roebling started America's first wire rope manufacturing company. He developed stronger cast steel wires for the Brooklyn Bridge and spun them on site to make them of sufficient length. Wire rope is made from strands of metal precisely organized to move together under load. =====

=
__**Designers:**__ The Bridge was designed by German-born John Augustus Roebling in Trenton, New Jersey. Roebling had earlier designed and constructed other suspension bridges, such as Roebling's Delaware Aqueduct in Lackawaxen, Pennsylvania, the John A. Roebling Suspension Bridge in Cincinnati, Ohio and the Waco Suspension Bridge in Waco, Texas, that served as the engineering prototypes for the final design.=====

=
Advantages: With the construction of this bridge, the gap between Manhattan and New York was covered allowing cars, trucks and pedestrians to cross over from one side to the other. This bridge has three lanes on each side for automobiles and a bicycle/pedestrian path in a higher level. The Brooklyn Bridge was designated a National Historic Landmark by the federal government and a National Historic Civil Engineering Landmark by the American Society of Civil Engineers. In recent decades, the landmark structure has been refurbished to handle the traffic demands during its second century. The bridge, which now accommodates six lanes of automobile traffic, carries approximately 145,000 vehicles per day (AADT). After nearly 120 years, the bridge still has the 44th longest main span among the world's suspension bridges.=====

=
Disadvantages: As a disadvantage there is the fact that there were a great number of accidents and deaths during the bridge construction. Some of the worst accidents happened during the cable rigging. For an instance, In June of 1878, a cable strand secured at the New York anchorage broke loose during adjustment. The strand flew over the New York tower and into the East River, taking off the top of one rigger's head and knocking another off the anchorage along the way. Another rigger was guiding wire onto a drum. He kicked at it to keep it in line, and his foot was caught. His leg was wrapped around the drum, killing him almost instantly. Several others died due to falls or falling equipment. At least three men died of the bends (caisson disease) during the caisson work. A couple of men were crushed by blocks being swung into place. All told, roughly 27 people died during the construction of the Brooklyn Bridge.=====

=
__**Conclusion:**__ John Roebling's predicted that the promenade above the deck will be "of incalculable value in a crowded commercial city" was justified; together with his perhaps most noted statement, claiming that "the great towers...will be ranked as national monuments. ...As a work of art, and a successful specimen of advanced bridge engineering, this structure will forever testify to the energy, enterprise, an and wealth of that community which shall secure its erection."=====