The earthquake on the night of the 7th, when strong shaking with a seismic intensity of over 5 was observed in Tokyo and Saitama Prefecture.
Not only did many people have difficulty returning home due to the suspension of the railway, but more than 75,000 elevators have stopped, and some have not yet been restored.
In addition, water leaks were found in 29 locations in the Tokyo metropolitan area due to damage to water pipes, which had a major impact on daily life.
Elevator confinement 28 cases No injuries
According to the Ministry of Land, Infrastructure, Transport and Tourism, 75,738 elevators stopped mainly in the Tokyo metropolitan area due to the earthquake on the night of the 7th, of which 28 cases were trapped in the elevators in Tokyo, Kanagawa, Chiba, and Saitama prefectures. It means that there was a case.
All the trapped people have already been rescued by the fire department, and no one has been injured.
As of the evening of the 8th, there are cases where it has not been restored.
On the other hand, in Minato Ward, Tokyo, the elevator of the building stopped due to the earthquake, and there are cases where it has not been restored even as of the evening of the 8th.
In the 9-story building in Higashi-Azabu, Minato-ku, Tokyo, where the offices and residences of the company are located, the elevator has stopped immediately after the earthquake on the night of the 8th.
Yaeko Kuwahara (84), the owner of the building, contacted a company that maintains and inspects elevators, and explained that "there are many elevators that require restoration work, and there is still no way to start work in this building." It means that.
After that, the company contacted me saying, "Recovery work will be done in the middle of the night or at dawn tomorrow."
Mr. Kuwahara puts a sticker at the entrance of the elevator to inform him of the stop, and asks the building users to use the stairs.
On the stairs to the 8th floor of the doctors and care helpers who visited the home visit
In addition, Mr. Kuwahara lives on the 8th floor with her husband who is bedridden and needs long-term care.
On the 8th, doctors and care helpers who visited her husband's home visit used the stairs to come to the room up to the 8th floor.
Mr. Kuwahara said, "I also have a bad knee and it is difficult to go up and down the stairs. I am worried about when the elevator will move. I want you to recover quickly."
Some people have more than 10 round trips to the 8th floor
In addition, Yutaka Koyamauchi, who is the president of a system development company that plans to open a new office on the 3rd floor of this building from next month, delivered 12 chairs and partitions from the shipping company on the morning of the 8th.
However, the elevator was stopped and the person in charge of the transportation company and two people carried the stairs more than 10 round trips.
Mr. Koyamauchi said, "It was very difficult to carry on the stairs because it was a large baggage. I think that it is unavoidable because the elevators are stopped in various buildings, but I hope that it will be restored soon." rice field.
Elevator First swaying feeling Stop at the nearest floor
According to the Ministry of Land, Infrastructure, Transport and Tourism, elevators have been obliged to install an "earthquake control operation device" from September 2009, and when they feel the first shaking of an earthquake, they stop at the nearest floor.
And if the shaking is not so great, the elevator door will open to prevent users from being trapped.
Inspection by a technician to restart The higher the floor, the longer it takes
Many elevators need to be inspected by a technician to safely stop and then restart.
The technician goes to the site to check if there are any abnormalities in the ropes and weights used to move the elevator, and then perform a test run.
However, the higher the number of floors in the building, the longer it takes to confirm the test run, and the technicians use the stairs, so it takes time to move for work.
For this reason, it may take some time to restore the elevator depending on the building.
Leakage due to water pipe breakage 29 locations in total in the Tokyo metropolitan area
According to the Ministry of Health, Labor and Welfare, as of 5 pm on the 8th, water leakage damage due to damage to water pipes was found in a total of 29 locations in the Tokyo metropolitan area.
Location
▽ Tokyo's 23 wards is 23 places to suit
▽ Misato City, Saitama Prefecture is three places
▽ Kawaguchi City, Saitama Prefecture is two places
▽ Ichihara, Chiba Prefecture, is in one place
that is already a repair has been completed except in Misato City That is.
In Misato City, repairs have already been completed at one location, and the remaining two locations are expected to be completed within 8 days.
There are no reports of water outage damage.
In addition, there are no reports of damage to medical institutions or social welfare facilities.
Expert "Is it the center of" short cycle "sway?"
Professor Yuki Sakai of the National Research Institute for Earth Science and Disaster Prevention, Kyoto University, who is familiar with the relationship between earthquake shaking and damage, analyzed the waveforms of seismographs installed by the National Research Institute for Earth Science and Disaster Prevention in various parts of the Kanto region.
As a result, it was found that the shaking with a short cycle of 1 second or less was conspicuous, and the shaking with a cycle of 1 to 2 seconds, which was prone to damage such as the collapse of structures such as houses, was small.
In Chiba City and Katsushika Ward, Tokyo, where seismic intensity 5 lower was observed, shaking with a short cycle of about 0.5 seconds is conspicuous.
Water pipes have been damaged one after another in this earthquake, but shaking with a cycle of less than 1 second is easy for people to feel, and in addition to mechanical equipment such as water pipes, furniture, roof tiles, block walls, etc. are damaged. It means that it will be easier.
Professor Sakai says, "In urban areas, the density of structures such as water pipes is high, so damage is likely to increase, and as a result, damage is thought to have occurred."
Is it a big ground effect due to shaking in a place away from the epicenter?
In addition, this time, the shaking became larger in Adachi Ward, Tokyo and Kawaguchi City, Saitama Prefecture, which are slightly far from the epicenter.
Regarding this, Professor Sakai points out the depth of the epicenter and the influence of the ground.
Professor Sakai said, "Since this earthquake occurred in a deep epicenter, the tremor was transmitted over a wider area, and it is thought that the tremor was amplified in areas where the surface ground was soft and the ground was not very good. In the case of a river, the surface of the reclaimed land is soft and liable to shake. The research institution discloses the condition of the ground, and I would like you to be aware of the easiness of shaking in your own home in advance and use it as a countermeasure. " ..
If an "earthquake directly under the capital" occurs, take measures against different damages
Furthermore, Professor Sakai pointed out that the expected "earthquake directly under the capital" is one size larger than this time, and shaking with a maximum seismic intensity of 7 is expected, so we would like you to take the opportunity to take measures against this earthquake as well. increase.
Professor Sakai said, "The magnitude of the expected" earthquake directly under the capital "is 7 classes, which is more than 30 times larger than this time. It is thought that the damage will not be necessary, and there is a risk of life-threatening damage such as the collapse of the building. I would like you to take this opportunity to take measures. "