Eads Bridge Summary
The Eads Bridge, located in downtown St. Louis, is the oldest remaining bridge across the Mississippi River, spanning over 145 years. Built by James Eads between 1867 and 1874, it was a groundbreaking engineering feat that connected St. Louis to the western United States.
Key Features:
- Oldest remaining bridge across the Mississippi River
- 145+ years old
- Truss bridge design with arches between piers
- Constructed using limestone, granite, iron, and steel from across the United States
- First use of chromium alloyed steel in bridge construction
- Tubular support systems for archways
Construction Challenges:
- Building during the steamboat era, requiring minimal obstruction to river traffic
- Going down to bedrock over 100 feet below the water’s surface to stabilize the bridge
- Using pneumatic caissons to scour out the river bottom and construct piers
- Workers faced intense air pressure, leading to the discovery of caisson disease (the bends)
Legacy:
- Over 1,500 people worked on the bridge, with 24 boats used in its construction
- Designed with replaceable parts for maintenance and longevity
- Still stands today as a testament to Eads’ innovative engineering and perseverance
- Offers a unique perspective on the city and the Mississippi River’s location and legacy
| Term | Definition | Example Usage |
|---|---|---|
| Truss Bridge | A type of bridge that uses a structure composed of connected elements to provide support and stability. | The Eads Bridge is an example of a truss bridge, with its arches between piers providing additional strength. |
| Pneumatic Caisson | A construction technique that uses compressed air to excavate and build underwater structures. | The Eads Bridge was constructed using pneumatic caissons to scour out the river bottom and build piers. |
| Caisson Disease | A medical condition that occurs when the body is exposed to rapid changes in air pressure, also known as the bends. | Workers on the Eads Bridge project suffered from caisson disease due to the intense air pressure during construction. |
| Chromium Alloyed Steel | A type of steel alloy that contains chromium, which provides increased strength and corrosion resistance. | The Eads Bridge was the first to use chromium alloyed steel in its construction, providing added durability. |
| Tubular Support System | A system of tubes or pipes that provide additional support and stability to a structure. | The Eads Bridge features a tubular support system for its archways, adding to its overall stability. |
| Bedrock | The solid, unbroken rock that lies beneath the earth’s surface, often used as a foundation for structures. | The Eads Bridge was built on bedrock, which was reached by going over 100 feet below the water’s surface. |
| Replaceable Parts | Components of a structure that are designed to be easily replaced or maintained, extending its lifespan. | The Eads Bridge was designed with replaceable parts to ensure its longevity and ease of maintenance. |
| Steamboat Era | A period in history when steam-powered boats were the primary mode of transportation on rivers and lakes. | The Eads Bridge was constructed during the steamboat era, requiring minimal obstruction to river traffic. |
| Groundbreaking Engineering Feat | An innovative and pioneering achievement in the field of engineering that sets a new standard or milestone. | The construction of the Eads Bridge was a groundbreaking engineering feat that connected St. Louis to the western United States. |
| Perseverance | The ability to persist and continue working towards a goal despite obstacles and challenges. | James Eads’ perseverance was key to the successful completion of the Eads Bridge project, despite the numerous challenges faced during construction. |
Eads Bridge Vocabulary Quiz
Test your knowledge of the Eads Bridge with the following 5-question multiple-choice quiz:
Answer Key:
- Arch bridge design with arches (Correct answer: Truss bridge design with arches)
- Caisson disease (the bends) due to intense air pressure
- Chromium alloyed steel
- Pneumatic caissons
- Over 1,500 people
Using the Present Perfect Continuous Tense to Describe Ongoing Situations
| The present perfect continuous tense is used to describe an action that started in the past and continues up to the present moment. It is formed using the present tense of the auxiliary verb “have” + “been” + the present participle of the main verb (e.g., “has been standing” or “have been working”). In the context of the Eads Bridge, this tense can be used to describe the bridge’s ongoing existence and the activities related to its construction and maintenance. For example, “The Eads Bridge has been standing for over 145 years” or “The engineers have been working on the bridge’s maintenance for decades.” |
|---|
Now, let’s test your understanding of the present perfect continuous tense with the following quiz:
1. The Eads Bridge ____________________ across the Mississippi River for over 145 years.
A) has stood
B) has been standing
C) was standing
D) stands
2. The engineers ____________________ on the bridge’s maintenance for decades to ensure its longevity.
A) work
B) have worked
C) are working
D) have been working
3. Over 1,500 people ____________________ on the bridge during its construction in the late 19th century.
A) have worked
B) worked
C) were working
D) had been working
4. The Eads Bridge ____________________ as a testament to innovative engineering and perseverance since its completion.
A) stands
B) has stood
C) had been standing
D) has been standing
5. The construction team ____________________ with intense air pressure while building the bridge’s piers.
A) has faced
B) faced
C) was facing
D) had been facing
Answer Key:
1. B) has been standing
2. D) have been working
3. B) worked
4. D) has been standing
5. B) faced
