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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girder are 45 x 3 inch flanges with a 144 x 0.75 inch web with stiffeners sized at 1 x 11 x 144 inch, placed 9 feet from each end and at 36-foot intervals across the girder. The 150-foot girder will have 18 x 2 inch flanges with a 62 x 0.5 inch web with stiffeners sized at 1 x 6 x 62 inch, placed 4 feet from each end and at 14-foot intervals across the girder. All girders will be braced for support with 4 x 4 x ½ angles at the location of each stiffener. The cost estimate for the superstructure is $29,269,187.82, which includes removal of both bridges but does not include any concrete for the deck or driving surface as the civil group included these in their cost estimate. INTRODUCTION The purpose of this report is to show the contributions that I have made throughout the semester to this project. This report will be broken into two sections. Section 1 will be my contribution to the first draft of the final report. Section 2 will be a narrative description of work I have performed that directly contributes to the final report. SECTION 1 The structural group determined that replacement of the Fairfax Bridge and also the Platte Purchase Bridge was the best approach to this project. Both bridges will be replaced will a single bridge that includes two lanes northbound, two lanes southbound and a shared use path. The superstructure of a bridge is the portion of the structure which supports traffic and includes the deck, slab and girders. The first step in designing the superstructure of the new bridge was to develop the overall length and span sections. The overall length was determined to be 2250 feet. With levees on both sides, a railroad on the Kansas side of the bridge and only one support allowed in the river, the three longer span lengths for the bridge were designed to be 450 feet with the other six spans to be 150 feet in length (Figure 1). The same span lengths were used in order to lower production costs for the steel girders. With only having two span lengths the resulting steel girders would be limited to two sizes needed. Figure 1: Profile view of US 69 Bridge With the bridge having two lanes in each direction, a shoulder for each lane, concrete traffic barriers on the outside and between each direction of traffic and a shared use path the overall width of the bridge was designed to be 77 feet with seven steel girders used as support (Figure 2). While the Missouri Department of Transportation (MoDOT) Engineering Policy Guide (EPG) recommends at least an 8.75-inch thick deck for bridges, we decided to use a 12-inch concrete deck to minimize the maintenance costs. Based on the MoDOT EPG 751.12.2.1 (MoDOT, 2015) the New Jersey type B barrier (Figure 3) was used for all concrete barriers on the bridge. Pedestrian fencing and chain link fencing were used for barriers along the shared use path. Figure 2: US 69 Bridge cross-section Figure 3: New Jersey Type B concrete barriers Before steel girders could be sized, the dead load and live load of the bridge had to be determined. The dead load is the weight of the entire bridge, which includes the concrete deck, the barrier weight and the steel girder weight. The live load is the loading that is applied from the vehicles that move across the bridge. The live load was determined by following the MoDOT EPG 751.2.2.1 (MoDOT, 2015) which states that a uniformly distributed lane load of 0.64 kip per linear foot should be used along with a design truck that has an 8 kip front axle load along with two 32 kip rear axle loads, the first of which is spaced 14 feet from the front axle and the second can vary from 14 feet to 30 feet. For analysis purposes the girder that would have to support the largest load was used for design. This section was determined to be directly under one of the driving lanes. Rapid Interactive Structural Analysis (RISA) software was use to determine the bending moment and the shear envelope that needed to be resisted by the steel girders. Each iteration of the girder size was input into the software beforehand to properly get the dead load for calculations. The final bending moment and shear envelope for each span length are shown in Figures 4 through 7. Figure 4: 450-foot girder required moment Figure 5: 450-foot girder required shear Figure 6: 150-foot girder required moment Figure 7: 150-foot girder required shear Both girders were designed to be stronger than the strength required to satisfy the moment and shear equations used for design.
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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kip Stiffeners are secondary plates, which are attached to girder webs to stiffen them against out of plane deformations. Local buckling occurs when a cross section is slender enough for buckling to occur within the cross section, due either to compression or shear. The webs of both girders used for the US 69 Bridge are slender and are vulnerable to local buckling. Transverse stiffeners are used in each girder to increase the resistance to local buckling. The 450-foot span has stiffeners placed 9 feet from each end and at 36-foot interval across the girder. The size of each stiffener plate is 1 x 11 x 144 inches (Figure 9). The 150-foot girder has stiffeners placed 4 feet from each end and at 14-foot intervals across the girder. The size of each stiffener plate is 1 x 6 x 62 inches (Figure 9). Figure 9: Both girders with stiffener placement and size Bracing between girders provides three main functions.
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
10). Figure 10: Bracing for each span The cost estimate of the superstructure (Table 2) was computed using the 2014 MoDOT Unit Price Data sheet provided to the class. The cost estimate includes removal of bridges, structural steel, concrete traffic barriers, chain link fence, and a pedestrian fence. The cost estimate does not include the bridge deck as the civil group used all road and deck costs in their cost estimate. The total cost estimate for the superstructure is $29,269,187.82.
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.
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
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...
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 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
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.
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.
A girder bridge is made up of girders which are beams that the end rests on piers or abutments. They can be used to cross most areas. The longest span of a girder bridge is 1,000 feet(300 meters) which is the same as a truss bridge. The two main types of girder bridges are box girder and the plate girder.
Fanella, D. (2011). Reinforced concrete structures: analysis and design / David A. Fanella. New York: McGraw-Hill, c2011.
Hailed as one of the finest films ever made, Jules and Jim adapted from the book with the same name, when projected today, can still generate an emotional effect that just as remarkable as the results provoked in the young viewers of 1960s. As a represent film of the French New Wave, Jules and Jim feels like a breath of fresh air injected into the French cinema in that era. Directed by the New Wave’s leading figure Francois Truffaut, Jules and Jim, against the conventional production known as the ‘tradition of quality’, used a free manner to launch an social experimentation, a creative revolution that has been forever recorded in the French film history. This essay will explore these innovative qualities contained in the film and the novel of Jules and Jim. It will firstly begin with the introduction of the revolutionary director Francois Truffaut and discuss his creativity in the film, then examine the French New Wave movement and its influence to the film of Jules and Jim.