Earthquake Resistant Building Design

Means of creating earthquake resistant buildings in an…

HIC

  •  Computer controlled weights in the roof help to reduce movement by travelling around to specific places to balance out the movement of the building, and help prevent it from toppling
  • Steel frames can sway, which reduces strain on the building during movement, so reducing the chance of a collapse
  • Automatic window shutters prevent any glass that breaks from falling on anyone
  • Open areas close to buildings allow anyone who has been evacuated to assemble. This allows people to be checked for so that emergency services know how many people are missing, and  means that even if something does collapse, it is less likely to fall on anybody
  • Foundations are sunk into the bedrock to avoid clays. Clay can easily enter liquefaction, which makes collapses more likely and also more devastating when  occur
  • “Birdcage” style interlocking frame on the exterior provides a stronger overall structure, meaning less of the building will collapse if there is damage
  • Panels are attached with flexible joins to the outside. Materials  to be flexible so that the sudden strains that the earthquake applies cause less damage, which stops them from bending or snapping
  • Road system built to allow quick access for emergency services. This allows faster response times after an earthquake, and helps limit secondary impacts, such as fires, from occurring, and saves some of the victims’ lives
  • Rubber shock- absorbers take the initial impact before the main foundations can be hit

 

LIC                         

  • Education and training – show people, especially poor people, how to build more robustly, and how to use resources more sustainably and cost-effectively
  • Incorporate new engineering techniques – lighty reinforced flat slab foundation below two layers of reinforced hollow concrete bricks (designed to cause minimal damage in the case of a collapse) forming the base of the wall, covered by damp proofing (to protect against moisture and insects). Wall frames formed of timber latticed with treated bamboo gives high strength and flexibility to a fairly light structure. Galvanised chicken mesh is attached to this so that outer materials, such as cement render can hang on it.
  • Replacing old materials – remove heavy clay roof tiles and replace them with a lightweight corrugated cement-fibreboard roof. This reduces the load on the walls, and in turn, both the chance of collapse and risk of injury if it does collapse
  • Reinforced steel corner pillars provide strength and flexibility to the structure
  • Any work with mixed stone pieces can use parts of other homes which collapsed during quakes- this would prevent the accumulation of debris, and quick action to gather it could assist aid workers.

 

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Philippines mudslide 2006

On 17th February 2006, a mudslide hit the village of Guinsagon in southern Leyte province in the Philippines. The slide covered 9km^2, was 3km wide and in places 30m thick. Half a mountain collapsed on the single village. .

Causes

The main cause of the mudslide was a La Ninya event in the Western Pacific. 200cm of rainfall fell in 10 days, weakening the slope strength. Slopes in the region are mostly very steep and mass movement and mudslides occur frequently.

Widespread deforestation during the past 70 years have also increased slope instability. The slide was ultimately triggered by a small local earthquake of magnitude 2.6Mw.

Exposure in that area of the Philippines is high. In 1991, 5,000 people were killed when typhoons triggered landslides, and a similar event in 2003 killed 133 people. Mudslides and landslides are a constant threat due to:

  • heavy and prolonged rainfall from typhoons
  • Steep hillsides largely built of weathered volcanic rock
  • Extensive faulting and earthquake activity

Many villages are located at the base of steep slopes in the direct path of mudslides, and rural populations are high. The people are very poor and have high population growth. Southern Leyte is one of the poorest areas of the Philippines. Between 1995 and 2000 the population grew by +2.73%, placing pressure on environmental resources.

Logging bans have not been enforced by the government, largely due to political corruption. Even where sustainable logging has been practiced, in many places trees with shallow roots have replaced trees with deep roots, and thus made the slopes far less stable.

Impacts

Survivors described how a “wall of mud” descended on the village, killing over 1,000 people, including 246 children at a primary school. Almost every one of the 300 homes was destroyed. The slide killed thousands of livestock and buried the farmland; around 16,000 people were affected.

Response

Hazard mitigation maps have been made of Southern Leyte, but are not very detailed, so that villages that will be effected by mudslides cannot be identified. Following heavy rains and the deaths of 20 people in a nearby village, warnings were issued between the 4th and 17th of February, and several hillside villages were evacuated. However, many people chose not to leave.

Evacuation centres were set up around St Bernard, the capital of the region. Emergency aid in these centres provided safe drinking water, sanitation and health services. The region is very poor, however, so they cannot afford communications, which slowed down response times. Two hundred rescue workers were brought into the site. Unlike earthquakes, mass movements have few survivors.

International aid was provided by the Red Cross and Red Cresent, and their appeal raised US$1.6 million.

The government has commissioned a US$1.5 million geohazards survey and mapping of Leyte to try to prevent future similar disasters.

Refugees and Italian Earthquakes

The earthquake struck on 24th August, 2016 at 3:36. It scored magnitude 6.2, with an epicentre close to Accumoli, with a depth of only 4km. 298 people were killed. There have been at least 2500 aftershocks, some of which, along with the initial quake, have been felt throughout most of Italy.

The Apennines are a very seismically active area, with many small faultlines. The faults involved recently in quakes have been SW-dipping faults.

Tourism to the rural area swelled the number of people around the area who could be affected by the earthquake. As such, 3 Brits and 11 Romanian people were killed by the earthquake.

At least 365 people had to be hospitalised, though many others had more minor injuries. 238 people were pulled out of rubble. A town near the epicentre, Amatrice, according to its mayor “is not here anymore”. Many cultural heritage sites have been lost- to the extent that structural tests were done on the Coliseum, on the other side of the country, 100km away. Dozens of people were killed in Rome, despite the distance from the epicentre.

Approximately 2,100 people went to emergency camps. 4,400 were involved in search and rescue with 70 teams with rescue dogs.

Italy has well developed emergency services which mobilised 6,600 rescue people overall. Rescue workers asked locals to turn off wifi passwords to help teams (and those needing assistance!) to communicate more easily.

A man trying to loot an empty home was arrested at one point.

A state funeral was held with coffins for 38 victims from Amatrice, including 2 children. The funeral was meant to be held in Reiti, 35 miles away, but local people protested, saying it had to be held locally, putting additional immediate strain onto builders and organisers, who were already struggling with organising basic needs. Another was held in the Marche region, nearby.

The Prime Minister, Matteo Renzi, has pledged 50 million euros in funds for rebuilding.

Refugees

In Pescara del Tronto, five asylum seekers helped out. Amadou Jallow from Gambia was one of them, and he said they had “to give back to Italian people for the good things that they have done for us”.

35 refugees and asylum seekers in Ascoli Peceno were shocked by the earthquake but started clearing rubble away quickly. A group of 70 refugees pooled their 2 euros a day allowance and made a donation of nearly 200 euros to earthquake victims- the footage they saw reminded them of the places they had fled from.

Italy generally has a very xenophobic attitude towards those of Muslim heritage- to the extent that in some schools refugee children are made to use different bathrooms to the others, due to “hygiene concerns” despite the children being perfectly healthy. Some of the intolerance is understandable:

  •  Since 2014, 400,000 refugees have arrived in Italy
  • Not all of them have enough housing
  • Not all can access schooling
  • Some politicians said the funding spent on refugees should have been spent on helping refugee victims instead.
  • Some victims think it better to be living in a migrant centre than the earthquake victim camps.
  • The emotional strain of the earthquake is going to put people on edge about any issues they encounter.

Any help the refugees gave was entirely from them understanding how stressful the situation was and genuinely wanting to help people in need; no one was trusting them enough to think they’d do anything to help.

Most don’t care about the prejudices- they’re grateful to live somewhere safe at last, and want to give back to their new communities. Some other examples of refugee community work:

  • Syrian teenagers in Seattle volunteering to help the homeless with basic necessities
  • A Syrian refugee setting up meal stations to give homeless people food in Berlin
  • Another Syrian refugee mobilising the refugee community to help in flooding in the British town they are living in.

Earthquake Proofing Controversy

Rieti was meant to have rebuilt many of its buildings after an earthquake in 1974 to improve earthquake resistance; however, an entire family was killed that sheltered within a church during the movement. A primary school in Amatrice was levelled- after 700,000 euros were spent in 2013 on “renovating” it; tests of the school’s permits shows that anti-seismic measures were faked, possibly by the mafia.

The Amatrice bell tower had been recently restored before the quake, but fell, and crushed a family of four.

 

Haiti Earthquake- Causes of Vulnerability

The temperature had been 28 degrees celsius average, with 137cm of rainfall average each year. This climate means that soil is often damp and therefore prone to moving easily.

The Caribbean plate moved east while the North American plate moved west. A large movement in the north section of the Caribbean plate occurred, causing the earthquake. Rocks break when the tension is released, which is what then causes the damage.

The earthquake was shallow, and the plates hadn’t shifted for years. The plate boundary ran through the capital, Port au Prince.

The epicenter was very close to Port au Prince, while the focus was not far underground.

Haiti is the poorest country in the western hemisphere, so was ill equiped for this situation. Building quality was awful- and they lacked infrastructure. They had poor architecture, and many buildings were made of low quality concrete blocks.Roo

Roofs easily collapsed, trapping people underneath. Many houses were on slopes, causing slips.

Haiti Earthquake- Short Term Impacts

The earthquake happened on the 12th of June 2010.

  • 1/3 of the buildings collapsed it the capital.
  • 200,000 people died.
  • 1/4 of a million people injured.
  • 1.3 million homeless
  • 300,000 buildings collapsed
  • Water, communications and electricity networks were all damaged
  • Little food or water available.
  • A million people forced to sleep in the streets
  • Billions of dollars worth of damage caused

Haiti Earthquake – Long Term Impacts

Due to knowledge that future quakes are likely to occur, various measures have had to be put into places.

Earthquake simulations are run to see the panic which would occur in the real situation. People can practice organising emergency services for the situation. They are also to see how children react. Lots of screaming and running around.

The emergency services are being trained to act as best they can, by staying calm instead of running around, for instance.

The earthquake has had the greatest effect on the poor long term.

Even before the earthquake, there were large inequalities. The earthquake worsened this.

Half of the population was below the poverty line; after the earthquake, this rose to 80%.

Haiti Earthquake- Long Term Management

Building resilience and Future capacity

Some people have had to spend 3 years in their camps. They had:

  • No money to build

NGOs helped the local people by:

  • Improving financial support for rebuilding
  • Improving infrastructure
  • Training stonemasons to make future settlements stronger
  • Building new settlements on outskirts

The relocated people would have had to still pay rent for housing had the refugee camps not been set up; the camps helped provide shelter for those who would not have been able to afford this in their current financial situation.

In the refugee camps, people had to travel to work. Often the fees of transport were so expensive that people could spend more money travelling to and fro between work and the camps than they would earn. So, many people had taken to just sleeping rough outside their offices during the week and only coming home at weekends.

There were toilets in the camps so there was one between every five families. One of the main aims of the new buildings was to remove this issue.

  • Have to travel to work
  • Spaced out buildings
  • No heavy tiles
  • Use local technology so homes can be fixed by local people.
  • Buildings were built with plenty of open spaces, so people can get away from falling buildings more quickly.
  • Buildings have only a few storeys, so there’s less to collapse in during future quakes, and also have timber frames, which are more flexible, so less likely to collapse in a future earthquake.
  • Lightweight structures, and only using light weight tiles means that if anything collapses in the future, it will be less damaging to anybody around.

 

 

Creditors died with the earthquake

  • Businesses have to be reset up again
  • Oxfam helped with this:
  • Financial security to support many businesses
  • Monthly allowances

Most food was imported.

Oxfam was trialing different techniques in Haiti to get good crop growth. Oxfam funded small rice mills to get a better price at the market for farmers. Unprocessed rice is worth far less, so by allowing the rice mills to be more available, farmers can get more profits, allowing rural areas to support themselves better in the aftermath. With more rice mills, it is overall cheaper to use them.

Profits from mills help pay for drainage channels which increase yield again. This is an overall positive multiplier effect.

Land reform is a necessary feature of the rebuilding. Before the earthquake, unclear laws on land ownership meant that when the earthquake hit, camps had to be built in poor sites as the owners could not be tracked down and asked permission to use any land closer to the capital. Most of the land is only claimed by a few people, and overall this makes it hard to make long term investments. Companies and investors want a guaranteed pay out, which they can’t get from the unclear laws as it was.

Alaska- Conflicts and Pressures

Oil

The USofA has high demands for oil and a desire to not be dependent on the supply given by other, typically less stable countries.

Oppositions to the exploitation of Alaskan oil were largely based on the fragile tundra ecosystem of the state.

  • Only a few cm of top soil thaw in the summer, so productivity is low in plant life
  • Below the arctic circle, the tundra makes way for taiga forest which has a variety of coniferous tree types
  • Supported by these environments are a wide variety of other species such as caribou, moose, bears, wolves and wolverines.

The US Government’s National Environmental Policy Act of 1969 meant that all companies had to consider the environment and recognise the rights of indigenous peoples.

  • To prevent permafrost melting, oil installations at well-heads are raised on mattresses
  • Dalton Highway (open since 1994) provides a supply route from the South to Prudhoe Bay in the North. It is built 2 m off the tundra surface on a bed of gravel and sand.
  • Workers at oil fields who do 2 week shifts through the year are flown in by Air Alaska from Anchorage (in the South) and lie in Deadhorse in raised, heated cabins
  • The Trans-Alaskan Pipeline, carrying oil 1,300 km from Prudhoe Bay to Valdez started being constructed in 1974 and was completed in 1977 at a cost of US$8 x 10^9. 5 pumping stations control oil flow. The pipeline is insulated and for most of its length is raised- both for access and to minimise environmental damage. The pipeline is built with a “zigzag” path to allow space for expansion of the pipeline in summer without the pipe breaking and leaking oil onto the tundra.
  • BP became the sole oil extractor at Prudhoe Bay in 2,000 but had to abandon parts of the oil field in 2009 as 900,000 litres of oil leaked from corroded pipes
  • In 1978 the Government increased areas of conservation in Alaska by 23 million hectare and by another 42 million in 1980

The oil is shipped out from Valdez by companies such as Exxon to refineries elsewhere in the USofA. Valdez is also dependent on commercial fishing.

 

  • The Exxon Valdez oil spill in 1989 damaged large sections of the coastline
  • Since 2006 some double-hull oil tankers, offering more protection against potential obstacles, have been operating in Alaskan waters.

The area also has a threat of earthquakes and tsunamis due to being on a destructive plate boundary.

Geological activity

On 27th March 1964 an earthquake measuring 9.2 on the Richter scale, epicentre 112 km East of Anchorage occurred resulting in land beside Prince William Sound sinking around 2 m. Tsunami over 30m high have hit Valdez before- Valdez has had to be relocated to a higher, safer site because of this.

Tourism

Tourism in Alaska is mainly concentrated in June, July and August, and in the South. Many visitors come in cruise ships.

  • Tourists are bused between National Parks to admire wildlife and scenery
  • Many anglers from around the world visit Alaska
  • Many ferries and tourist vehicles also carry rangers who identify wildlife and geographical features

Fires

32% of Alaska is covered in forest. There are 4.8 million hectares of commercial forest

  • In 2004, 272 fires were caused by lightning and 424 by people One by Dalton Highway destroyed 195,576 hectares of forest

Ash from fire can release minerals which help plant growth and also leaves areas of the forest floor exposed to sunlight so more plants can grow there.

Population

In 2,000 Alaska had 626,932 residents, and now has 736,732 in 2016.

  • To safeguard subsistence lifestyles, a government act in 1980 gave the rural people priority in hunting and fishing on federal lands. There have been subsequent disputes between rural and urban Alaskans, due to claims of being discriminated against. It is difficult for wardens to enforce this.
  • Alaskan residents have benefited from oil revenue. In 1976 the Alaska Permanent Fund was established. At least 25% of all money earned from minerals goes into this fund. By 1980 oil revenues had allowed Alaska to abolish income taxes. Alaska is now the 4th richest US state.

Politics

The Arctic may have up to 25% of the world’s undiscovered oil and gas reserves. In 2007, Russia put claims to the Arctic which has created tensions with other Arctic nations and territories, including Denmark (Greenland), Norway and Canada, as well as the USofA

 

(Image Sources: http://www.d.umn.edu/~hoef0049/pbpipeline.html http://www.pbs.org/wgbh/amex/pipeline/map/ http://nws.noaa.gov/com/weatherreadynation/news/140319_alaska.html)