Earthquakes are natural disasters that cause immense damage to life and property. They not only leave thousands of people homeless, but also ruin the lives of millions across the globe. Earthquakes affect many parts of the world every year. Every year, more than 50 thousand people die from earthquakes. Since 1990, earthquakes have been responsible for more than 800 thousand deaths and have left 17+ million people homeless. The annual damage resulting from earthquakes is estimated to be USD 35 Billion.
Also, earthquakes further lead to tsunamis and volcanic eruptions causing even more damage. The destructive effects of earthquakes are from landslides, tsunamis, fires, and fault rupture. The violent shaking of the ground produces the greatest property losses and personal injuries.
Earthquake destruction begins with the earth’s violent shaking that can rupture the earth, trigger landslides and turn the surface of the earth to liquid. The damaging shaking of major earthquakes can be felt hundreds of miles away. Ground shaking is the vibration of the ground during an earthquake. The shaking triggers other hazards such as liquefaction and landslides. Most earthquake damage results from the seismic waves passing beneath buildings, roads, and other structures. The primary earthquake hazard is surface rupture. It can be caused by vertical or horizontal movement on either side of a ruptured fault. Ground displacement, which can affect large land areas, can produce severe damage to structures, roads, railways and pipelines.
An earthquake generated within the Pacific Ocean floor will generate a tsunami, which is actually a series of very long waves. Large tsunamis which travel to the ocean floor to the surface are dangerous to human health, property, and infrastructure. Long lasting effects of tsunami destruction can be felt beyond the coastline. Earthquake damage facts show fires caused by earthquakes are the second most common hazard. Earthquake fires start when electrical and gas lines are dislodged due to the earth’s shaking. Gas is set free as gas lines are broken and a spark will start a firestorm.
In earthquakes, although much of the human losses derive from damage to urban housing, the economic impact instead arises from damage to critical infrastructure such as transport including communications, airports, passenger rail, roadways; fuel and energy, electric, and water systems. Furthermore, significant interdependencies can exist between infrastructure systems in an urban area, meaning that damage to one system may result in disruption to other critical infrastructure.
Earthquake prone countries
Earthquakes refer to shaking of earth caused when large plates (size of continents) below the surface of earth continually push against each other and at certain time, one of the plates may slide over one another. The impact of an earthquake (at any location) is characterized by two primary characteristics, Intensity measured commonly on Ritcher Scale which measures magnitude of the event on Logarithmic scale which means that an earthquake measuring 6.0 is 10 times more powerful than an earthquake measuring 5.0. The second is Epicenter, that denotes the exact location, where the earthquake originated.
Several million earthquakes occur worldwide every year according to statistics collected and reported by the U.S. Geological Survey. Most of these are of the low magnitude variety and, on average, less than 1,500 quakes register anything higher than a magnitude-5 score. About once a year, however, some area of the world is rocked by a tremor which surpasses a magnitude-8 score, which can cause considerable damage to entire communities and shift buildings from their foundations.
Japan tops the list of the earthquake prone areas. The country has a long history of witnessing disastrous earthquakes since it is situated on the Pacific “Ring of fire”. If estimates are to be believed, a citizen in Nepal is more likely to be killed by an earthquake as compared to any civilian in the world.
Ecuador has several active volcanoes making the country an extremely dangerous for high- magnitude quakes and tremors. India has also experienced a series of some deadly earthquakes due to the movement of the Indian tectonic plate at the rate of 47 mm every year. Due to the movement of tectonic plates, India is prone to Earthquakes. In Philippines, earthquakes with high magnitude have led to deadly volcanic eruptions in the past. Indonesia is quite vulnerable to earthquakes as well as other natural disasters.
Another earthquake prone country is Pakistan, which is geologically situated atop the Eurasian and Indian tectonic plates. Mexico is another earthquake prone country, which has faced several earthquakes of high magnitudes in the past. China is another most earthquakes prone country, with its more than 49 percent of its territory and 50 percent of its urban area being located in high intensity quake zones.
In April 2015, magnitude-7.8 earthquake resulted in deaths in Nepal as well as in neighboring countries India. China and Bangladesh. A major aftershock registering a magnitude-7.3 hit the same region a few weeks later, killing dozens and injuring thousands. By mid-May, the official death toll from both quakes surpassed 8,500 people and the disaster became the deadliest earthquake to ever strike the country of Nepal.
In California, the collapse of buildings, roads and infrastructure produced eight of the ten costliest earthquakes in the last one hundred years. The U.S. Geological Survey reports there is a 72 percent probability that an earthquake of magnitude 6.7 or larger will strike the San Francisco Bay area within the next 30 years. Southern California has a 60% chance of experiences an earthquake measuring magnitude 6.7 in the same timeframe.
Tools and technologies
There is no natural disaster sneakier than an earthquake. Hurricanes can be predicted and tracked weeks in advance, and even tornados, monsoons and blizzards at least have seasons. But earthquakes strike entirely without warning.
Many new tools and techniques are being developed through large research and development efforts that are saving thousands of lives from this disaster. Technology can play very important role in preventing disasters, rapidly respond and deliver relief care to the affected population after an earthquake, search for survivors, provide backup to damaged critical infrastructure including communications e.t.c.
Technologies such as seismographs, creepmeters, and laser beams are used to detect seismic events. A seismograph is an instrument designed to measure earthquake intensity and seismic vibrations during an earthquake.
Social media apps like Facebook and Google have developed tools designed to help users quickly learn that their contacts are in a safe place. Facebook’s Safety Check identifies which contacts are safe and which are yet unaccounted for, while Google’s Person Finder operates as a missing person database.
Earthquake Early warning
Earthquake early warning systems use earthquake science and the technology of monitoring systems to alert devices and people when shaking waves generated by an earthquake are expected to arrive at their location. The seconds to minutes of advance warning can allow people and systems to take actions to protect life and property from destructive shaking.
There are a few seconds between an earthquake starting to rupture and its possibly devastating effect on population and infrastructures. Earthquake Early Warning (EEW) Systems address the issue of how to take advantage of this delay by triggering alerts and actions that may mitigate losses. The first weaker seismic signals (P waves) radiated by a potentially damaging earthquake travel about twice as fast as the later large amplitude (S or surface waves) that are more likely to cause damage. The information about the earthquake source size and location, as inferred from real-time processing of the early seismic waves collected in the vicinity of the source, can be sent to more distant sites in advance of the arrival of strong shaking.
EEW Systems are advanced seismic monitoring infrastructures able to detect the ongoing event, estimate its potential damage and send a warning to a target site. Such a warning can alert a community and activate security measures, that may contribute to the real-time vulnerability reduction to minimize losses, or in directing rescue operations immediately after an earthquake for emergency preparedness.
Even a few seconds of warning can enable protective actions such as:
Public: Citizens, including schoolchildren, drop, cover, and hold on; turn off stoves, safely stop vehicles.
Businesses: Personnel move to safe locations, automated systems ensure elevators doors open, production lines are shut down, sensitive equipment is placed in a safe mode.
Medical services: Surgeons, dentists, and others stop delicate procedures.
Emergency responders: Open firehouse doors, personnel prepare and prioritize response decisions.
Power infrastructure: Protect power stations and grid facilities from strong shaking.
US earthquake early warning system
The backbone of an earthquake early warning system is a widespread and robust network of seismometers. In the United States, the first regional seismic networks were begun by research institutions and universities like Caltech; University of California, Berkeley; and the University of Washington. These regional networks and others were later brought together and coordinated by the Advanced National Seismic System (ANSS) in 2000.
Around the same time that ANSS formed, seismometers were advancing from analog to digital recordings, which allowed them to log data much more quickly and accurately. Additionally, high-bandwidth data communications were becoming more common, allowing seismic stations to quickly transmit their data across greater distances.
Meanwhile, other countries had set up or begun exploring earthquake early warning systems of their own, often following tragic earthquake disasters. Mexico, for example, began its public earthquake early warning system in 1991 after the deadly 1985 magnitude 8.0 Guerrero earthquake, while Japan began theirs in 2007, spurred on by the lethal 1995 magnitude 6.9 Kobe earthquake. Scientists and planners in the United States hoped to be able to put those hard-learned lessons in effect here before a deadly earthquake struck within our borders. The stage was now set for the United States’ own earthquake early warning system, which would come to be known as “ShakeAlert.”
A demonstration EEW system called ShakeAlert began sending test notifications to selected users in California in January 2012. The system detects earthquakes using the California Integrated Seismic Network (CISN), an existing network of about 400 high-quality ground motion sensors. CISN is a partnership between the USGS, State of California, Caltech, and University of California, Berkeley, and is one of seven regional networks that make up the Advanced National Seismic System (ANSS). Earthquake early warning systems like ShakeAlert work because the warning message can be transmitted almost instantaneously, whereas the shaking waves from the earthquake travel through the shallow layers of the Earth at speeds of one to a few kilometers per second (0.5 to 3 miles per second).
When an earthquake occurs, both compressional (P) waves and transverse (S) waves radiate outward from the epicenter. The P wave, which travels fastest, trips sensors placed in the landscape, causing alert signals to be sent ahead, giving people and automated electronic systems some time (seconds to minutes) to take precautionary actions before damage can begin with the arrival of the slower but stronger S waves and later-arriving surface waves. Computers and mobile phones receiving the alert message calculate the expected arrival time and intensity of shaking at your location. It is reported that Chinese seismic network showed dramatic increase in speed of response by releasing the preliminary report within few minutes of the earthquake hit.
Disaster management is a system to save lives and properties developed under huge costs and efforts of years. Many earthquake casualties could be prevented with more accurate systems for locating survivors trapped under thousands of pounds of collapsed rubble. The most fundamental activities to save lives during the emergency response period include: (1) Initial situation assessment (2) Search and rescue (3) First aid (4) Evacuation. The time duration from all above factors may continue for some days to weeks or months looking after the condition of severity.
In general, first seventy-two hours are considered as emergency response period. in this scenario initial situation assessment is considered as primary prerequisite for the effective and efficient earthquake emergency response. Which is a response activated just after the earthquake, it is necessary to know the extent of damage area and location of trapped victims where a rapid response team must be available there without wasting a minute. Deprived of accurate and holistic initial situation assessment the improper resource allocation could be happen especially in the first twelve hours.
Nowadays, the technology and modern tools are providing great support for rescue teams to assess the initial situation just after an earthquake, which include Remote Sensing (RS), Unmanned Aerial Vehicles (UAVs), Emergency Calls, Social media etc. All the above techniques have their own features as well as some disadvantages. For instance, remote sensing (RS) give the spatial extent observation of the damage within a short time (depending on the post disaster data accessibility) but it cannot provide information about the trapped victims which is a disadvantage of RS.
After analyzing the initial situation of the affected areas the Earthquake Emergency Response (EER) is conducted including search and rescue operation. A physical void search, audible call-out, use of fiber optics, search cameras, infrared/thermal imaging, electronic search and canine search are some of the common techniques used in search operation. Some of the other techniques including disaster response robots, FINDER (Finding Individuals for Disaster and Emergency Response) and Unmanned Aerial Vehicles (UAVs) are also used within a limited scale
After extricating the trapped victims, the next operation during an EER is first-aid and following TRIAGE for large numbers of causalities could be a primary option(TRIAGE in field) or in case of secondary option (TRIAGE by emergency physicians or surgeons of patient’s arrival at the hospital) and tertiary (TRIAGE i in ICU or Radiology)
Integration of smart watch and Geographic Information System (GIS)
Nowadays, the emergency managers and rescue teams are using GIS system because of its potential and capacity in all phases of earthquake disaster management. GIS is used as an indicator and an identifier for the earthquake emergency teams for handling of earthquake’s situation with powerful and in more energize way of reaction. GIS has the potential to minimize the impact of earthquakes by rapid risk assessment and locations’ tracking in the comparison of populations, property, and natural resources. The GIS is helpful in the determination of rare resources assignment, search priority, rescue tasks, assessment of short- and long-term recovery operations.
In all the types of GIS, the smartphone, smart-watch, smart notebook and smart TV are some powerful tools used for emergency response in disaster management making the 21st century as the age of smartness. Smart watches have distinct advantages over traditional watches. Smart watches are defined as wrist worn mini devices, which contains computational power and can be used for wireless connectivity, notification alerts, collecting and storing personal data through several different sensors . The efficiency of the existing earthquake emergency response by using real-time data from smart watches worn by victims and geographic information system (GIS).
NASA Technology Finds Nepal Survivors by Their Heartbeats
Two prototype units of that system, called Finding Individuals for Disaster and Emergency Response (FINDER), were sent to Nepal in the days following the April 25 earthquake. An international team of rescuers from several countries using the FINDER devices found two sets of men under two different collapsed buildings.
FINDER unit, about the size of a carry-on bag, is powered by a lithium battery and sends out low-power microwaves. The waves can detect subtle movements, such as the slight pulsing of skin that reveals a heartbeat. The waves can penetrate up to about 30 feet (9 meters) into mounds of rubble or 20 feet (6 meters) into solid concrete. One of the advantages of FINDER over microphones or other traditional search and rescue tools is that a person doesn’t have to be conscious to be found—the person just needs to have a pulse.
Nissan technology can Power Your House from Car
Nisan has developed a charging system running on a Nissan Leaf electric car that can be used to supply electricity to a house during a power outage or shortage. A two-way charging device that would typically convert the household electricity supply to a voltage suitable for charging the car’s battery can be reversed to feed power back into the household circuit. The technology can be very useful in earthquakes like Fukushima Daichi, that can severely damage power generation capability. The lithium ion batteries in a Leaf can store up to 24kWh (kilowatt hours) of electricity, which Nissan estimates is sufficient to power an average Japanese home for about two days.
Scientists began suggesting the idea of using robots for search-and-rescue operations in the 1980s. They were driven by the prospect of bots that could operate in a range of environments, from underground tunnels to volcanic craters to the twisted maze of concrete created when buildings collapse. In short, they wanted robots that could go to places that are unreachable — or simply too dangerous — for human rescuers. Since past few decades, robots have taken an increasingly active role in these rescue efforts. Bots have battled their way through major events like the World Trade Center attacks, hurricanes Katrina and Harvey, the Fukushima Daiichi nuclear disaster and the eruption of Hawaii’s Kilauea volcano. From wheeled vehicles to drones, robots have been used in dozens of disasters over the past few decades.
These mechanical saviors can range from ground to marine to aerial vehicles — including drones that don’t just rummage through rubble for survivors, but provide reconnaissance from above. Beyond that, roboticists across the globe are building new, inventive types of rescue robots. Many projects still in development draw inspiration from the animal kingdom, mimicking designs that nature has perfected to make machines that can move through harsh environments, from droids that resemble snakes and cockroaches to a fleet of autonomous bees. And while many are still years away from being used in actual crises, they point toward a future in which — contrary to much of science fiction, where bots bring death and destruction — it’s the robots that come to our rescue.
Meanwhile, roboticists across the world were working to make more agile robots that could operate in extreme environments. With those two catastrophes as catalysts, the notion of search-and-rescue robotics shifted from an abstract idea into the domain of applied research. In the U.S., those efforts were led by Murphy, while in Japan, they were spearheaded by roboticist Satoshi Tadokoro; together, they are considered the founders of the field of disaster robotics.
“The Japanese had been working on large robots,” says Murphy. “[They] wanted big robots to rapidly remove rubble.” In the U.S., on the other hand, the emphasis was on building smaller robots to first locate people who were trapped within collapsed structures, and then figure out how to get to them. “[Both approaches] were very measured, with safe engineering practices,” she adds. “But they were two different approaches.”
For the past 20 years, scientists at the Carnegie Mellon lab have worked to develop snake robots. By tweaking previous robotics designs, they created a “unified snake robot,” or U-snake, made up of a series of identical, jointed modules that allow the bot’s body to take on a variety of shapes to move through different types of terrain. Snakes are a perfect model because their unique shape and range of motion allow them to thread through tightly packed spaces, like a collapsed building.
Earthquake resistant design
It is poor quality buildings which kill people, not earthquakes. The buildings also need to be designed to be earthquake resistant. The strengthened building codes have enhanced their survivability in both Ecuador and Japan, contributing to reduced death tolls in recent events.
Research conducted at Imperial College London, has led to the development of a structural connection for buildings which is fitted at points throughout a building’s framework to capture shockwave energy and help it to dissipate safely. The use of rubber bearings in a building’s foundation to isolate it from the ground, separating it from the tremors felt during an earthquake, has also been suggested as a useful technique for preventing damage to structures.
Iran has spent $4.5 billion on ensuring that 95,000 schools for 13 million students are safe against earthquakes, floods and fire, since the Bam earthquake which claimed over 30,000 lives in 2003. Over 80 percent of the work is complete. The deputy Prime Minister of Turkey, Yalçın Akdoğan, announced that over 11,000 unsafe buildings have been demolished since the emergency management authority AFAD was established in 2009. Hundreds of schools have been rebuilt and critical infrastructure including tunnels and bridges has been reinforced.
University of Missouri researchers have developed a new metamaterial to help buildings withstand the ground shockwaves from earthquakes
The longitudinal and sheer energy waves produced by an earthquake travel through the ground and can destroy buildings miles from the epicentre. Preventing that damage requires a solution that can withstand these multidirectional waves travelling through a solid material but that is also flexible.
Enter metamaterials, a term for artificially constructed material, usually a composite, engineered in patterns that give them unique properties often to do with the way they manipulate waves. Dr Guoliang Huang, a James C. Dowell Professor in the mechanical and aerospace engineering department at the University of Missouri’s College of Engineering leads a team that has developed a lattice-type material that protects against both types of wave and is flexible enough to wrap around the objects it is protecting – a building or vehicles, for example.
The polar metamaterial is an ideal material for elastic wave cloaking. It is constructed by a lattice structure that can bend waves or vibrations so that objects inside the polar metamaterial coating are untouched by these waves or vibrations. Therefore, it is particularly useful for protecting against vibrations that might damage a structure. The polar metamaterial was fabricated by 3D printing. We performed static tests with tension and shear loadings. We are planning to do dynamic testing in the near future, said Dr Guoliang Huang.
The US Army Research Office funds the research, which has clear defence applications, including protection against vibration in mechanical parts, such as aircraft or submarine engines, and flexible protection for soldiers and equipment against blast energy. Two papers on the research, ‘Polar metamaterials: a new outlook on resonance for cloaking applications’ and ‘Physical realization of elastic cloaking with a polar material’, were published in Physical Review Letters, a journal of the American Physical Society.
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