Keep A Watchful Eye On The Bridges Reading Passage
Keep A Watchful Eye On The Bridges Reading Passage
Paragraph A:
The Interstate 40 bridge over the Rio Grande River in Albuquerque provided the researchers with a rare opportunity to test their ideas. Chuck Farrar, an engineer at Los Alamos, explains: “The New Mexico authorities decided to raze this bridge and replace it. We were able to mount instruments on it, test it under various load conditions, and even inflict damage just before it was demolished.” In the 1960s and 1970s, 2500 similar bridges were built in the US. They have two steel girders supporting the load in each section. Highway experts know that this design is “fracture critical” because a failure in either girder would cause the bridge to fail.
Paragraph B:
After setting up the microwave dish on the ground below the bridge, the Los Alamos team installed conventional accelerometers at several points along the span to measure its motion. They then tested the bridge while traffic roared across it and while subjecting it to pounding from a “shaker”, which delivered precise punches to a specific point on the road.
Paragraph C:
“We then created damage that we hoped would simulate fatigue cracks that can occur in steel girders,” says Farrar. They first cut a slot about 60 centimeters long in the middle of one girder. They then extended the cut until it reached the bottom of the girder and finally, they cut across the flange – the bottom of the girder’s “I” shape.
Paragraph D:
The initial, crude analysis of the bridge’s behavior, based on the frequency at which the bridge resonates, did not indicate that anything was wrong until the flange was damaged. But later the data were reanalyzed with algorithms that took into account changes in the mode shapes of the structure – shapes that the structure takes on when excited at a particular frequency. These more sophisticated algorithms, which were developed by Norris Stubbs at Texas A&M University, successfully identified and located the damage caused by the initial cut.
Paragraph E:
“When any structure vibrates, the energy is distributed throughout with some points not moving, while others vibrate strongly at various frequencies,” says Stubbs. “My algorithms use pattern recognition to detect changes in the distribution of this energy.” NASA already uses Stubbs’ method to check the behavior of the body flap that slows space shuttles down after they land.
Paragraph F:
A commercial system based on the Los Alamos hardware is now available, complete with the Stubbs algorithms, from the Quatro Corporation in Albuquerque for about $100,000. Tim Darling, another Los Alamos physicist working on the microwave interferometer with Migliori, says that as the electronics become cheaper, a microwave inspection system will eventually be applied to most large bridges in the US. “In a decade I would like to see a battery or solar-powered package mounted under each bridge, scanning it every day to detect changes,” he says.
Paragraph G:
Most road and rail bridges are only inspected visually, if at all. Every few months, engineers have to clamber over the structure in an attempt to find problems before the bridge shows obvious signs of damage. Technologies developed at Los Alamos National Laboratory, New Mexico, and Texas A&M University may replace these surveys with microwave sensors that constantly monitor the condition of bridges.
Paragraph H:
“The device uses microwaves to measure the distance between the sensor and the bridge, much like radar does,” says Albert Migliori, a Los Alamos physicist “Any load on the bridge – such as traffic-induced displacements, which change that distance as the bridge moves up and down.” By monitoring these movements over several minutes, the researchers can find out how the bridge resonates. Changes in its behaviour can give an early warning of damage.
Also See: IELTS Academic 2024 Reading Resources
Keep A Watchful Eye On The Bridges Reading Questions and Answers
Discover exciting and informative IELTS reading answers about Keep A Watchful Eye On The Bridges
Questions and Answers 1-4
1. How did the traditional way to prevent damage to the bridges before the invention of the new monitoring system
- Bridges have to be tested in every movement on two points.
- Bridges have to be closely monitored by microwave devices.
- Bridges have already been monitored by sensors.
- Bridges have to be frequently inspected by professional workers with naked eyes.
2. How do the new microwave monitors find out the problems of bridges?
- by changeling the distance between the positions of the devices
- by controlling the traffic flow on the bridges
- by monitoring the distance caused by traffic between two points
- by displacement of several critical parts in the bridges
3. Why did the expert believe there is a problem with the design called “fracture critical”
- Engineers failed to apply the newly developed construction materials.
- There was not enough finance to repair the bridges.
- The supporting parts of the bridges may crack and cause the bridge to fail.
- There were bigger traffic load conditions than the designers had anticipated.
4. The defect was not recognised by a basic method in the beginning
- until the mid of the faces of bridges fractured.
- until the damage appears along and down to the flanges.
- until the points on the road have been punched.
- until the frequency of resonates appears disordered.
Keep A Watchful Eye On The Bridges Reading Answers with Explanations (1-4)
Type of Question: Multiple Choice Questions
These types of questions in IELTS reading involve identifying the right choice from the given options using the given paragraph.
How to best answer:
- Understand the Context: Read the entire passage carefully to grasp the overall context and main ideas before answering questions.
- Identify Keywords: Focus on keywords in the question and options. Match these keywords with specific information in the passage.
- Eliminate Wrong Choices: Use the process of elimination to rule out clearly incorrect options, narrowing down your choices.
- Look for Synonyms: Be aware of synonyms or paraphrased terms in the passage that may differ from those in the question or answer choices.
- Double-Check Your Answers: Ensure that your selected answer fits grammatically and logically within the context of the passage.
Reference: From Paragraph A, "Most road and rail bridges are only inspected visually, if at all. Every few months, engineers have to clamber over the structure in an attempt to find problems before the bridge shows obvious signs of damage."
Explanation: Traditional methods involved visual inspections where engineers physically examined the bridge structure every few months to detect issues before they became visible. This method was less advanced and relied heavily on manual observation.
Reference: From Paragraph H, "The device uses microwaves to measure the distance between the sensor and the bridge, much like radar does. Any load on the bridge – such as traffic-induced displacements, which change that distance as the bridge moves up and down."
Explanation: The new microwave monitors measure the distance between the sensor and the bridge by detecting changes caused by traffic loads. These changes in distance, due to the bridge’s movement, help identify any potential structural problems.
Reference: From Paragraph C, "Highway experts know that this design is 'fracture critical' because a failure in either girder would cause the bridge to fail."
Explanation: The design was termed "fracture critical" because it relies on the integrity of each steel girder. If one girder fails, it compromises the entire structure, leading to potential bridge collapse.
Reference: From Paragraph D, "The initial, crude analysis of the bridge’s behaviour, based on the frequency at which the bridge resonates, did not indicate that anything was wrong until the flange was damaged."
Explanation: Initially, basic frequency analysis did not detect the damage until it became severe. It was only when the flange was damaged that the problem was identified, demonstrating the limitations of early detection methods.
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Questions and Answers 5-8
Keep A Watchful Eye On The Bridges Reading Answers with Explanations (5-8)
Type of Question: Diagram Labelling
To answer a Diagram Labelling question in the IELTS reading section, carefully examine the diagram provided and match the labelled components or sections with the corresponding information found in the passage.
How to best answer:
- Read Instructions Carefully: Ensure you understand what is required, noting word limits and specific instructions.
- Examine the Diagram: Familiarize yourself with the diagram, noting labels, arrows, and any provided details.
- Identify Keywords: Look for keywords in the questions and match them with parts of the diagram.
- Use Context Clues: Use any provided text to help understand the diagram and find the correct labels.
- Stay Within Word Limits: Ensure your answers fit within any given word limits and match the exact requirement.
Reference: From Paragraph B, "After setting up the microwave dish on the ground below the bridge, the Los Alamos team installed conventional accelerometers at several points along the span to measure its motion."
Explanation: The microwave dish was positioned on the ground beneath the bridge to gather data on the bridge’s structural behavior. It emitted microwave signals that interacted with the bridge, allowing the team to track any movements or displacements. This data was crucial for detecting any potential issues or changes in the bridge's condition over time.
Reference: From Paragraph B, "After setting up the microwave dish on the ground below the bridge, the Los Alamos team installed conventional accelerometers at several points along the span to measure its motion."
Explanation: Conventional accelerometers were strategically placed at various locations along the bridge to monitor its movement and vibrations. These devices recorded the bridge’s dynamic responses to loads and forces, providing essential data on how the structure behaved under different conditions. This information helped in assessing the bridge’s overall stability and identifying any potential problems.
Reference: From Paragraph A, "In the 1960s and 1970s, 2500 similar bridges were built in the US. They have two steel girders supporting the load in each section."
Explanation: The bridges referred to were designed with two steel girders per section, which were crucial for supporting and distributing the load across the structure. These girders played a vital role in maintaining the bridge's stability and strength. Understanding this design was important for evaluating the potential risks associated with these bridges, particularly in terms of their susceptibility to structural failure.
Reference: From Paragraph C, "They first cut a slot about 60 centimeters long in the middle of one girder. They then extended the cut until it reached the bottom of the girder and finally, they cut across the flange – the bottom of the girder’s 'I' shape."
Explanation: The researchers intentionally created damage by cutting a slot in the girder, extending it downwards until it reached the flange, which is the horizontal section at the bottom of the girder’s 'I' shape. This deliberate cutting was meant to replicate fatigue damage and simulate the real-world impact of structural stress. By doing so, they could test the effectiveness of the new monitoring system in detecting such critical structural issues.
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Questions and Answers 9-13
9. how is the pressure that they have many a great chance to test bridges - ____
10. a ten-year positive change for microwave device - ____
11. the chance they get an honorable contract - ____
12. explanation of the mechanism for the new microwave monitoring to work - ____
13. how is the damage deliberately created by the researchers - ____
Keep A Watchful Eye On The Bridges Reading Answers with Explanations (9-13)
Type of Question: Matching Information
These types of questions involve reading the descriptions or statements provided, identifying key details or keywords, and matching them to corresponding information in the passage by comparing and contrasting the options until you find the best fit.
How to best answer:
- Skim the Passage: Quickly read through the entire passage to get a general idea of the content and structure.
- Identify Keywords: Look for keywords or phrases in the questions that are easy to locate in the passage.
- Scan for Keywords: Scan the paragraphs for the keywords or synonyms, and focus on those sections.
- Read in Detail: Once you find a potential match, read that section carefully to ensure it contains the specific information needed for the question.
- Check All Options: Make sure to check all relevant paragraphs, as the correct information might be mentioned in more than one place.
Reference: From Paragraph A, "We were able to mount instruments on it, test it under various load conditions, and even inflict damage just before it was demolished."
Explanation: The opportunity to test the bridge under various load conditions before its demolition allowed researchers to gather crucial data on its structural integrity and performance, which would not have been possible under normal circumstances.
Reference: From Paragraph F, "In a decade I would like to see a battery or solar-powered package mounted under each bridge, scanning it every day to detect changes."
Explanation: The anticipated development and deployment of affordable, battery or solar-powered microwave inspection systems across most large bridges represent a significant positive shift in bridge monitoring technology, enhancing daily structural surveillance.
Reference: From Paragraph G, "Technologies developed at Los Alamos National Laboratory... may replace these surveys with microwave sensors that constantly monitor the condition of bridges."
Explanation: The introduction of advanced microwave sensor technologies, developed at Los Alamos and Texas A&M, presents an opportunity for significant contracts, as these technologies offer a more effective and continuous solution for bridge condition monitoring.
Reference: From Paragraph H, "The device uses microwaves to measure the distance between the sensor and the bridge... Any load on the bridge – such as traffic-induced displacements, which change that distance as the bridge moves up and down."
Explanation: The new microwave monitoring system works by measuring changes in distance between the sensor and the bridge, similar to radar. This measurement detects variations caused by loads and movements, which helps in identifying changes in the bridge’s behavior and potential damage.
Reference: From Paragraph C, "They first cut a slot about 60 centimeters long in the middle of one girder... and finally, they cut across the flange."
Explanation: Researchers created damage by cutting a slot and extending it to the girder’s bottom, then cutting across the flange. This simulated realistic fatigue cracks, allowing them to test how effectively their monitoring system could detect and analyse such structural issues.
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