This report covers the superstructure design of the new US 69 Bridge proposal along with a cost estimate for this portion of the project. The old bridges will be replaced with a new four-lane bridge along with a shared use path. The dimensions of this bridge are 77 feet across and 2250 feet in length. Traffic barriers will be placed along the edge, between traffic directions and between traffic and the shared use path.
A total of nine spans will used with three being 450 feet in length and six being 150 feet in length. 70 kips per square inch steel will be used for all structural members. Seven girders will be used for each span, all with slender webs, compact flanges and transverse stiffeners for buckling support. The dimensions for the 450-foot
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This was done to accommodate future additions that might be added to the bridge as this would add weight and increase the bending moment and shear envelope. The final design uses 70 kip per square inch steel for all girders with the 450-foot span girder having both flanges sized at 45 x 3 inches with a web of 144 x 0.75 inches (Figure 8). The 150-foot girder has both flanges sized at 18 x 2 inches with a web of 62 x 0.5 inches (Figure 8). The design moment and shear resistance for both girder sizes is shown in Table 1. Figure 8: Dimensions for each girder size
Table 1: Required and design parameters for each girder size
Span Required Moment, MU Required Shear, VU Design Moment, ΦMN Design Shear, ΦVN
450 Foot 107,725 kip * ft 904 kip 110,340 kip * ft 963 kip
150 Foot 11,195 kip * ft 254 kip 13,242 kip * ft 560
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The first is for control of buckling in the main girders during construction. The wet concrete imposes significant bending of the bare steel girders and the compression flange needs to be restrained against buckling. The second function is that bracing can be used to distribute the vertical bending effects between the main girders, and to ensure that lateral effects such as wind loading and collision loading are shared between all the girders. The third function is dimensional control, as a result of unequal loading, the horizontal distance between the flanges of adjacent girders will vary if not constrained. Bracing was placed at every transverse stiffener location for both girder sizes. 4 x 4 x ½ inch angles were used for bracing elements (Figure
71,300 tons of structural steel, 931,000 tons of concrete 42,000 miles of cable wire weighting 11,840 tons, 4,851,700 steel rivets and 1,016,600 steel bolts were all used in the building of the Mackinac Bridge. 1,024,500 tons in total weight is what all this ends up weighting to (Mackinac Bridge 3) (Mackinac Bridge 8). The Main Mackinac Bridge towers reach 554 ft above water and 210 ft beneath the surface to bedrock (Mackinac Bridge 8). To contain temperature changes, high winds and changes of weight on the Mackinac bridge, the deck can move left or right as much as 35 ft at center span. (Mackinac Bridge 9). The total Building time of the bridge was 48 months/ 4
It became a link between Fort Erie, Canada and Buffalo, New York. The bridge is over one mile long, 5,800 feet, and holds three lanes of traffic. The center lane may go north or south depending on the volume of traffic. In 1934, the Great Depression caused a change.
A connecting rod subjected to an axial load F may buckle with x-axis as neutral axis in the plane of motion of the connecting rod, {or} y-axis is a neutral axis. The connecting rod is considered like both ends hinged for buckling about x axis and both ends fixed for buckling about y-axis. A connecting rod should be equally strong in buckling about either axis [8].
At the time of its construction in 1929, the Ambassador Bridge was the largest spanned suspension bridge at 564 meters until the George Washington Bridge was built. It was an engineering masterpiece at the time. The total bridge length is 2,286 meters and rises to 118 meters above the river. Suspension cables support the main span of the Ambassador Bridge and the main pillars under the bridge are supported by steel in a cantilever truss structure. In total, the McClintic-Marshall masterpiece is comprised of 21,000 tons of steel. The immense socio-economical impact that the Ambassador Bridge has on transportation and trade is imperative for daily interaction between the Un...
The area of where the bridge was to cross the Ohio River was said to be one of the hardest places to build but came with some advantages. The section of the river had a solid rock base for the supporting pier to be built on. Since the engineers knew they could build a pier that would not settle they decided on a continuous bridge design. This design type distributes the weight so the steel trusses could be smaller and riveted together. This alone saved an estimates twenty percent of steel that was originally thought to be need to make the bridge cutting down the cost. The two continuous trusses span a collective 1,550 feet across the water. With addition of the north and south approach viaducts, for trains to go under the bridge, the superstructure’s total length is 3,463 feet. The bridge was made to hold two sets of tracks making the width 38 feet and 9 inches. The design called for 27,000 cubic yards of concrete and 13,200 tons of steel with some members being four foot square beams that span a distance of seventy feet. The design was the first step in a long process that would take several years to
According to Suspension bridges: Concepts and various innovative techniques of structural evaluation, “During the past 200 years, suspension bridges have been at the forefront in all aspects of structural engineering” (“Suspension”). This statement shows that suspension bridges have been used for over 200 years, and that people are still using them today because they are structurally better bridges. This paper shows four arguments on the advantages of suspension bridges, and why you should use one when building a bridge. When deciding on building a suspension bridge, it has many advantages such as; its lightness, ability to span over a long distance, easy construction, cost effective, easy to maintain, less risk
The architecture and engineering firm hired with the task of designing and constructing the tower, SOM, assigned Bruce Graham and Fazlur Khan to the project. They implemented a bundled tube design that was the first of its kind on such a large project that paved the way for the design and construction of future skyscrapers. This design allowed for 4.5 million square feet of office space, more customization of the floor layouts, up to 3 foot of sway within the building, and the stiffness needed to stay standing at the height in which it was built. The tubular design also allowed Sears to save about $10,000,000 on steel alone compared to previously used steel frame designs. Additionally, SOM managed to save 95% of the time usually spent welding by using prefabricated parts referred to as Christmas trees. This not only majorly sped up the process, but allowed Sear to save on labor costs. In addition to 3 trussed layers in the building, there were trusses and spandrel beams designed into every floor to help the load distribute more evenly.
People who thinks of Thornton Wilder primarily in terms of his classic novella “Our Town,” The Bridge of San Luis Rey will seem like quite a switch. For one thing, he has switched countries; instead of middle America, he deals here with Peru. He has switched eras, moving from the twentieth century back to the eighteenth. He has also dealt with a much broader society than he did in “Our Town,” representing the lower classes and the aristocracy with equal ease. But despite these differences, his theme is much the same; life is short, our expectations can be snuffed out with the snap of a finger, and in the end all that remains of us is those we have loved.
Based on the research conducted, the bridge being built will be a Pratt or Parker Bridge with a height of about 2.5 inches. Members will connect to one another through lap joints, and when a lap joint cannot be used, an end joint with two gussets securing it in place will be used. Gorilla Glue and Alteco ST50 Super Glue will be used to connect members at these joints. The glue will be applied to balsa members pinned to a workspace through a glue applicator to assist in applying a precise amount of
Because the cable stayed design allowed for support towers on the land rather than in the water, this avoided potential collisions from large ships with the support piers. The bridge deck itself was constructed in 10metre concrete segments, with the first three segments initially supported by the scaffolding (as seen in Fig 4.2.2). During construction, each segment cast of the land size was also paired with an equal segment over the water to ensure they were all adequately balanced. This segments would individually weigh around 460 tonnes. Upon the completion of the tower, the first stay cables were installed and attached to the allocated slots within the tower.
Works Cited Journal articles: • Lane, Thomas. “Crazy Angles, Soaring Steel.” Building vol. 274 no. 8588 (28) 2009, July 17, pp. 40-46.
Fanella, D. (2011). Reinforced concrete structures: analysis and design / David A. Fanella. New York: McGraw-Hill, c2011.
The height of the beam was determined for purposes of calculating the moment of inertia. Maximum permissible loads were calculated for quarter span and Midspan. The beam was loaded at the midspan in 5lb and increments done until the maximum limit was reached and the deflection recorded. The procedure was repeated for quarter span. The beam dimensions were recorded and the area moment of inertia determined. The safe loads at the mid-span and at the end of cantilever were calculated and the beam was loaded with 2lb at the mid span until the maximum load limit was attained. Deflection was determined at each point of increment. The procedure was repeated in a free end beam. A convenient reference point on the beam was chosen for deflection measurements. A single concentrated load was placed at some point and the deflection determined. The first load was removed and a second load placed at a different point and deflection determined. Both loads were applied simultaneously and the resulting deflection determined. Two non-symmetrical reference points were chosen on the beam and concentrated load (P1) applied at one point at deflection determined. The load was removed from the first reference point and a different load placed at a second reference
The one that looks like a long box that lies between the piers or abutments is the box girder. Box girders are made of steel or concrete. The plate girder looks like a T or an I if you look at the end of the beam. It supports the bridge on two