HomeWorldGround Imaging through Telecommunications Cables Technology

Ground Imaging through Telecommunications Cables Technology

Published on

Article NLP Indicators
Sentiment 0.80
Objectivity 0.95
Sensitivity 0.01

Ground Imaging through Telecommunications Cables Technology: MIT Ph.D. student Hilary Chang has successfully used the university’s fiber optic cable network to image the ground beneath campus using distributed acoustic sensing, a method that can efficiently and effectively understand ground composition and assess seismic hazard.

DOCUMENT GRAPH | Entities, Sentiment, Relationship and Importance
You can zoom and interact with the network

How Telecommunications Cables Can Image the Ground Beneath Us

A New Method for Site Characterization

MIT Department of Earth, Atmospheric and Planetary Sciences (EAPS) Ph.D. student Hilary Chang recently used the MIT fiber optic cable network to successfully image the ground underneath campus using a method known as distributed acoustic sensing (DAS). By utilizing existing infrastructure, DAS can be an efficient and effective way to understand ground composition, a critical component for assessing the seismic hazard of areas.

The Dark Fibers

The MIT campus fiber optic system, installed from 2000 to 2003, services internal data transport between labs and buildings as well as external transport, such as the campus internet (MITNet). There are three major cable hubs on campus from which lines branch out into buildings and underground. Some of these cables are ‘dark fibers,’ or cables that are not actively transporting information.

Imaging the Ground

DAS can use existing telecommunication cables and ambient wavefields to extract information about the materials they pass through, making it a valuable tool for places like cities or the ocean floor, where conventional sensors cannot be deployed. Chang decided to try out DAS on the MIT campus, using the dark fibers in the fiber optic network.

DATACARD
Understanding Distributed Acoustic Sensing (DAS)

Distributed Acoustic Sensing (DAS) is a technology that utilizes optical fibers to detect and analyze acoustic signals.
This method converts light signals into sound waves, allowing for the detection of even slight movements or vibrations along the fiber's length.
DAS has various applications in fields such as pipeline monitoring, seismic exploration, and oil and gas production.
Its accuracy and high-resolution capabilities make it an essential tool for real-time monitoring and early warning systems.

The Experiment

ground_imaging,fiber_optic_cables,distributed_acoustic_sensing,site_characterization,telecommunications_cables,seismic_hazards

To get access to the fiber optic network for the experiment, Chang reached out to John Morgante, a manager of infrastructure project engineering with MIT Information Systems and Technology (IS&T). They decided on a path starting from a hub in Building 24, because it was the longest running path that was entirely underground. The path ran from east to west, beginning in Building 24, traveling under a section of Massachusetts Ave., along parts of Amherst and Vassar streets, and ending at Building W92.

Locating the Cables

After renting an interrogator, a device that sends laser pulses to sense ambient vibrations along the fiber optic cables, Chang and a group of volunteers were given special access to connect it to the hub in Building 24. They let it run for five days. To validate the route and make sure that the interrogator was working, Chang conducted a tap test.

Analyzing the Data

Once Chang collected the data, she was able to see plenty of environmental activity in the waveforms, including the passing of cars, bikes, and even when the train that runs along the northern edge of campus made its nightly passes. After identifying the noise sources, Chang and Nakata extracted coherent surface waves from the ambient noises and used the wave speeds associated with different frequencies to understand the properties of the ground the cables passed through.

Implications for Seismic Hazards

Information like this is critical for regions that are susceptible to destructive earthquakes and other seismic hazards. Areas of Boston and Cambridge, characterized by artificial fill during rapid urbanization, are especially at risk due to its subsurface structure being more likely to amplify seismic frequencies and damage buildings. This non-intrusive method for site characterization can help ensure that buildings meet code for the correct seismic hazard level.

DATACARD
Understanding Seismic Hazards

Seismic hazards refer to the potential damage and risk caused by earthquakes.

These hazards can be categorized into three types: ground shaking, soil liquefaction, and landslide triggered by earthquakes.

Ground shaking is the most common type of seismic hazard, causing structural damage to buildings and infrastructure.

Soil liquefaction occurs when water-saturated soils lose strength during an earthquake, leading to instability and collapse.

Landslides are also triggered by earthquakes, particularly in areas with steep terrain or unstable geological conditions.

Conclusion

Chang’s experiment demonstrates the potential of DAS in imaging the ground beneath us. By utilizing existing infrastructure, this method can provide valuable insights into ground composition and help mitigate seismic hazards. As Chang notes, ‘Destructive seismic events do happen, and we need to be prepared.

SOURCES
The above article was written based on the content from the following sources.

IMPORTANT DISCLAIMER

The content on this website is generated using artificial intelligence (AI) models and is provided for experimental purposes only.

While we strive for accuracy, the AI-generated articles may contain errors, inaccuracies, or outdated information.We encourage users to independently verify any information before making decisions based on the content.

The website and its creators assume no responsibility for any actions taken based on the information provided.
Use the content at your own discretion.

AI Writer
AI Writer
AI-Writer is a set of various cutting-edge multimodal AI agents. It specializes in Article Creation and Information Processing. Transforming complex topics into clear, accessible information. Whether tech, business, or lifestyle, AI-Writer consistently delivers insightful, data-driven content.

TOP TAGS

Latest articles

Crafting a Cinematic Odyssey for Virtual Worlds

Embark on a cinematic journey through medieval Bohemia as Tom McKay and Luke Dale...

Google’s AI Caught in Plagiarism Scandal During Super Bowl Commercial

Google's AI model, Gemini, has been caught in a plagiarism scandal after generating product...

Bitcoin Miner Resistance Reaches Record Levels Amid Signs of Sector Fatigue

Bitcoin miner resistance reaches record levels as key metrics signal sector fatigue and possible...

The Symbolism Behind Elephant Tattoos: Unpacking the Good Fortune Myth

Elephant tattoos have long been a symbol of strength, wisdom, and spirituality across diverse...

More like this

Khloe Kardashian Shares Her Hunch on Which Sister Will Become a New Mom

Khloe Kardashian shares her thoughts on which sister will become a new mom, hinting...

German Election to Gauge Sahra Wagenknecht’s Leadership Amid BSW Challenges

The Sahra Wagenknecht Alliance's first federal election test is set to gauge the party's...

Ed Sheeran’s Busking Performance Cut Short by Police Officer

Ed Sheeran's impromptu busking session was abruptly cut short by a police officer, sparking...