Question

Argentina is considering constructing a bridge across the Rio de la Plata to connect its northern coast to the southern coast of Uruguay. If this bridge is constructed, it will reduce the travel time from Buenos Aires, Argentina, to Sao Paulo, Brazil, by over 10 hours and has the potential to significantly improve the flow of manufactured goods between the two countries. The cost of the new bridge, which will be the longest bridge in the world, spanning over 50 miles, will be $700 million. The bridge will require an annual maintenance of $10 million for repairs and upgrades and is estimated to last 80 years. It is estimated that 550,000 vehicles will use the bridge during the first year of operation, and an additional 50,000 vehicles per year until the tenth year. These data are based on an a toll charge of $90 per vehicle. The annual traffic for the remainder of the life of the bridge life will be 1,000,000 vehicles per year. The Argentine government requires a minimum rate of return of 9% to proceed with the project.

(a) Does this project provide sufficient revenues to offset its costs?
(b) What considerations are there besides economic factors in deciding whether to construct the bridge

Answer 1

The construction of a bridge between Argentina and Uruguay requires a financial analysis to determine its economic viability and a careful engineering analysis to ensure structural integrity and safety, considering past engineering disasters like the Tacoma Narrows Bridge collapse.

Step-by-step explanation:

The construction of a bridge, such as the proposed one across the Rio de la Plata to connect Argentina and Uruguay, requires meticulous planning and analysis to ensure both its economic viability and structural integrity. If Argentina is considering constructing a bridge to improve the flow of manufactured goods between the countries and reduce travel time, determining whether the project will provide sufficient revenues to offset its costs involves a financial analysis. Using the given data and assuming a 9% rate of return required by the Argentine government, calculations must be done to see if the projected toll collection will meet or exceed the initial and ongoing costs of the bridge over its 80-year lifespan.

Beyond economic factors, decision-making should include consideration of environmental impacts, cultural and social effects, feasibility of design, and safety. The history of bridge construction teaches valuable lessons, such as the importance of physics in design, as explored in the case of the Golden Gate Bridge and the Tacoma Narrows Bridge collapse. These examples highlight the critical role of utilizing science and mathematics in engineering to prevent disasters and ensure long-lasting structures. The failures of past projects, like the collapse of the Tacoma Narrows Bridge due to resonance, stress the necessity for thorough design and engineering practices.

Additionally, other design-induced disasters like the crashes of the British comet jets have led to significant changes in design practices within industries. Thus, while the economic analysis might suggest a project's feasibility, extensive engineering evaluations must conclude its safety and practicality. These considerations are vital for achieving successful and sustainable engineering outcomes.

Answer 2

Argentine Bridge Across the Rio de la Plata

a. The project provides sufficient revenues to offset its costs.

b. Non-economic factors deciding the bridge construction include:

Social connections and enhancement of relationships

Reduction of travel time

Infrastructural development

Step-by-step explanation:

a) Data and Calculations:

Reasons for constructing the bridge:

Connect northern Argentine coast to the southern coast of Uruguay

Reduce travel time from Buenos Aires to Sao Paulo by 10 hours

Improve the flow of manufactured goods between the two countries

Longest bridge in the world, spanning over 50 miles

Cost of the new bridge = $700 million

Annual maintenance cost = 800 million ($10m * 80 years)

Total cost of new bridge $1,500 million

Minimum required rate of return = 9% of $1,500 million ($135 million)

Estimated Revenue from the new bridge:

Vehicles using the bridge:

1st Year to 10th year = 550,000 each

Basic number of vehicles using the bridge = 5,500,000

Additional vehicles per year until tenth year = 50,000

Total additional vehicles = 450,000 (50,000 * 9)

Total number of vehicles using the bridge for the first 10 years = 5,950,000 (5,500,000 + 450,000)

Annual vehicular traffic from 11th year to 80th year = 1 million per year

Total from 11th to 80th year = 70 million ( 1 million * 70)

Overall vehicular traffic throughout the bridge's life = 75,950,000 (70,000,000 + 5,950,000)

Toll charge per vehicle = $90

Total revenue = $6,835,500,000 (75,950,000 * $90)