The first example of an external force is the static (dead) load, this refers to the gravitational forces acting on the bridge itself. Every structure has to be able to support the weight of its own materials in order for it not to collapse, this is before any live load is applied to it. Another example is dynamic (live) load which refers to traffic, from people or vehicles, which move across the bridge and apply additional weight to it increasing the magnitude of vertical forces acting on the bridge. But environmental factors such as changes in temperature, precipitation and winds can also create vertical and horizontal loads on the bridge. (Bagga
Building a Waddell A-Truss Bridge Introduction: Bridges have been used for thousands of years, beginning with natural formations, such as huge rock arches (Appendix A). The first bridges made by humans were most likely simple spans of wooden tree trunks laid across streams, or planks, such as rafts tied together (Gascoigne, 2001). These simple designs evolved over time, as new materials became available, to form the hundreds of bridges we use today. Some basic bridge designs include truss, arch, beam and suspension bridges. The most basic of these is the beam bridge (Appendix B1), which consists of a deck, spanning a relatively short distance, that is held up by a pair of abutments (vertical supports at either end). When weight is placed on
Arch Bridges: A simple arch bridge reaches across the river in an arching shape rather than straight across the river. Gravity, the weight of the bridge and all the weight creates a downwards force. But since the bridge is curved the force becomes a downwards outward force. Rather than
Case History In the late 19th century, the transportation demands of Quebec and other provinces success in transportation like Montreal’s success in railways led to proposals for bridging the St. Lawrence River. Quebec Bridge has a long story behind it, a bridge that was proposed first back in 1852 but it was not complete until 1919. It collapsed two times in this duration once in 1907 killing 75 workers and second time in 1916 killing 13 workers. In this report I will emphasize on the first collapse.
This used engineering because we had to design a scale drawing of each piece and measurement in the design. There was only little room for human error for it could have been fatal for the design. This was a much harder project than the rest and it took a substantial amount of skill to develop a good plan for the bridge. This made the students think and perform precise (as always) measurements. Lots of math was involved in the building in the bridge.
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
Calculations and load and failure predictions Calculations were performed to determine the effectiveness of the design of the platform. Allowing for a safety factor of 1.5 times the design weight of 10kg and considering the bridge must not be overdesigned; plans were made for the bridge to fail at 25kg, 2.5 times that of the design weight. According to the calculations, the bridge would hold a load of over 15kg and experience failure at 20kg in the members. These calculations were later disproven in the testing, breaking 8kg earlier than expected, due to unforseen errors. An analysis of the bridge design and calculations has been included at the end of this report.
Staring at engine components of a car as well as holding a smartphone with almost unbelievable thickness fascinated me in many ways indirectly leaded me into getting to know more through different sources about machines ranging from transportation to communication devices. Two
Problems Occurred: Furthermore, when the millennium bridge opened within the first weekend around 100,000 people had crossed the bridge. Due to such heavy traffic, this lead to something called resonance. Resonance is when the input vibrations frequency coincides with the natural frequency of the structure itself, causing large deflections to develop. The issue caused the bridge to undergo a swaying movement; hence led to its closure. After extensive research and analysis, it was found that the movement was caused by synchronized pedestrian footfall. To prevent this there were two options taken into account the lateral stiffening and the damping; both were used in order to increase the natural frequency of the structure so it did not match the footfall. In addition structures called fluid-viscous dampers and tuned mass dampers were installed to control both horizontal and vertical movements.
Newton’s first law of motion describes that an object in motion will stay in motion unless acted on by an outside force. Newton’s first law can also be called the law of inertia. This is true because inertia is an object resisting a force, until being acted on, and the first law states an object in motion will stay in motion unless acted on by an outside force, hence giving it the nickname, law of inertia. Newton 's first law happens all the time and can also be very simple.
Each group will be introduced to a bridge study unit. Teachers will cover academic material of different bridge structures in relation to U.S. common core standard requirements for social studies, science, and math. Students in Group B will be asked to select a bridge discussed in the unit. Then, they are asked to draw a blueprint for a bridge of their own inspired by the bridge they selected. Once their blueprint is complete, at a later date they are asked to construct a bridge from their blueprint with various materials that the teacher will supply. During each part of this assignment students are reminded to use/include the math and science concepts that were taught in the bridge unit. Bridge blueprints and constructions done by Group B will be presented to the class for evaluation and a benchmark test will also be dispensed to all students in Group A and Group B to collect data for
Professor Farquharson made an important observation- the bridge model underwent a “twisting motion” when faced with certain extreme conditions. From his model, he could conclude that in the event that the actual bridge
TESL 301 Different types of Bridges-Research Paper Because of advancements in today’s technology in construction field, many types of bridges are being constructed depending on the requirement and their suitability for the situations. A bridge is a structure providing path over an obstacle. When constructing a bridge, obstacle can be a river,
The independent variable is the different materials that I will use to make three bridges of the same common design, the truss design which uses triangular beams because triangles are the strongest shape to use when you build bridges. The materials that I will use to make these 3
Another strange thing about these bridges is their behavior in wind. The suspension bridge has a reputation of swaying in the wind, but how can this be possible with a road on top of it? Surely