Foundation System of Burj Dubai

Foundation System: The Tower is founded on a 3700mm thick high performance reinforced concrete pile supported raft foundation at -7.55 DMD. The reinforced concrete raft foundation utilizes high performance Self Compacting Concrete (SCC) and is placed over a minimum 100mm blinding slab over waterproofing membrane, over at least 50mm blinding slab. The raft foundation bottom and all sides are protected with waterproofing membrane.

See figure above for the Raft Foundation System. The piles are 1500mm diameter, high performance reinforced concrete bored piles, extending approximately 45 meters below the base of the raft. All piles utilize self compacting concrete (SCC) with w/c ratio not exceeding 0.30, placed in one continuous concrete pour using the tremie method. The final pile elevations are founded at -55 DMD to achieve the assumed pile capacities of 3000Tonnes.

Raft Foundation System

A robust cathodic protection system for both the bored piles and the raft foundation system protects the foundation and the reinforced concrete raft against the severe and corrosive environment (chloride and sulfate)
of the soil at the Burj Dubai site.

Layout of Raft Foundation System

Lateral Load Resisting System of Burj Dubai

Lateral Load Resisting System

The tower’s lateral load resisting system consists of high performance, reinforced concrete ductile core walls linked to the exterior reinforced concrete columns through a series of reinforced concrete shear wall panels at the mechanical levels.

The core walls vary in thickness from 1300mm to 500mm. The core walls are typically linked through a series of 800mm to 1100mm deep  reinforced concrete or composite link beams at every level. 


Due to the limitation on the link beam depth, ductile composite link beams are provided in certain areas of the core wall system. These composite ductile link beams typically consist of steel shear plates, or structural steel built-up I-shaped beams, with shear studs embedded in the concrete section. The link beam width typically matches the adjacent core wall thickness.

At the top of the center reinforced concrete core wall, a very tall spire tops the building, making it the tallest tower in the world for all categories. The lateral load resisting system of the spire consists of a diagonal structural steel bracing system at level 156.

Floor Framing System


 The residential and hotel floor framing system of the Tower consists of 200mm to 300mm two-way reinforced concrete flat plate slabs spanning approximately9 meters between the exterior columns and the interior core wall. The floor framing system at the tips of the tower floor consists of a 225mm to 250mm two-way reinforced concrete flat plate system. The floor framing system within the interior core consists of a two way reinforced concrete flat plate system with beams.

Foreshock, Main shocks, Aftershocks and Earthquake Swarm

When a series of earthquakes with shallow focal depths occur within a limited time and area and if there is an event, which is much larger than the rest, this event is called the main shock. Earthquake occurring before the main shock are called aftershocks. A series of earthquakes without a main shock is called an earthquake swarm.

The patterns of earthquake occurrence in tome domain can be generally divided into three groups:

1. Foreshock-main shock-aftershock,

2. Main shock-aftershock, and

3. Earthquake swarm.

Foreshocks are rarely observed while aftershocks are always observed after every large earthquake. Foreshocks are important for earthquake prediction and aftershocks are vital for the study of the mechanism of the rupture of the main shock. The area where aftershocks occur is called the aftershocks region. The distances from the focus and the epicenter to an observation point are called focal distance and epicenter distance respectively. The observation point is termed the station. Seismic destruction propagates from the focus through a limited region of the surrounding earth body, which is called the focal region. The larger the earthquake, the larger the focal region. When evaluating earthquake parameters, it should be kept in mind that the data may contain inaccuracies. The dates of old earthquakes are often not accurate in the catalogs and descriptions of the size of the earthquake and its effects are sometimes imprecise. For recent earthquakes, the data are usually accurate. Origin time is known with an accuracy of a few seconds for earthquakes in the second half of the 20^th century. The accuracy decreases with elapsed time and depends on the number of recording stations and on the accuracy of the time service. Most instrumental epicenters are now determined with a standard error of 10 – 20 km; the earlier instrumental determinations are known with a low accuracy varying according to the number, position, and reliability of recording stations.  

Skid Steer Bucket Concrete Mixer

A skid-steer bucket concrete mixer is a skid-steer forklift attachment that combines the benefits of a loader and a concrete mixer into a single piece of equipment. With this innovative and compact piece of equipment, your company can combine the benefits of a loader and a concrete mixer into a single device. This one of a kind concrete mixer allows you to produce thoroughly mixed concrete quickly and efficiently without the assistance of a third party and with no time delays. It also allows you to transport the concrete to pour sites located in areas too small for larger concrete mixers to reach.

A skid steer-bucket concrete mixer features a design that allows it to be lowered like a bucket to scoop sand and gravel. The mixer can then be tilted back into the upright position, exposing a bag splitter that allows you to break bags of cement and pour their contents directly into the unit. You can then add water, mix it with the sand, gravel, and cement, have concrete ready to pour in a matter of minutes. The skid-steer bucket concrete mixer discharges its contents either through a chute on the side, or by being tilted downward. This allows the unit greater flexibility in reaching hard to get to places.

Skid steer bucket concrete mixers provide work crews with an economic alternative to manual loading that can lead to back injuries. They save a great deal of time for work crews who normally have to wait on ready-mix companies to bring in trucks. It is much better to get the job done right then and there without having to depend on a third party that may actually charge you for more materials and services than you actually need. Because ready-mix companies tend to avoid selling small quantities of concrete, contractors often have to meet minimum volume requirements when ordering concrete, plus they have to pay for the labor.

With a smaller, bucket concrete mixer you can control yourself, you can pay for only the materials that you need. Existing work crews on site can handle the mixing, and you don't have to wait for delivery. Adding the bucket concrete mixer to your skid-steer, you can transform an existing piece of equipment with a simple attachment that minimizes procurement costs and better enables you to meet project deadlines.

A number of features enable skid-steer bucket concrete mixers to function in a fast, ergonomic, and accurate manner. A new, improved design uses a revolving paddle to mix cement. This method is much more efficient than the use of augers and produces a more blended constituency. These paddles are driven by a hydraulic motor that attaches to your skid-steer's hydraulic system through a chain and sprocket drive. This eliminates the need for a separate power source, and it allows the skid-steer itself to power the concrete mixer. The chain and sprocket drive also allow for paddle reversal and protect the skid-steer bucket from shock.

While skid-steer bucket concrete mixers are made for cement mixing, not mixing grout, they can be adapted to mixing grout if you incorporate 3/8" of pea gravel into the mix design. The total grout or concrete mixing capacity of the skid steer bucket is 9 cubic feet. These attachments are intended for mounting on universal quick-tach skid-steers rated at 1600lbs or greater.

Sanitary Landfill Site Selection

The following important factors must be considered when evaluating potential landfill sites for disposal of solid wastes:

1. It is important to ensure that sufficient land area is available for disposal of solid wastes for a reasonable period of time, preferably greater than one year 9(minimum), because for short periods, the disposal operation becomes more expensive.

2. Haul distance will have significant impact on operating cost. Although minimum haul distances are desirable, other factors like collection route location, local traffic patterns and access conditions must also be considered.

3. It is important that the cover material should be available at or near the landfill site. Therefore the soil conditions and topography of the site must be considered,

4. Climate conditions, e.g., wind patterns and local surface water hydrology of the area has to be considered because these will have impact on the access to landfill sites.

5. Geologic and hydrogeologic conditions are the most important factors in establishing the environmental suitability of the area and are required to assess the pollution potential of the proposed site. It is to be ensured that the movement of leachate and the gasses from the landfill will not contaminate the ground water aquifer.

6. Extreme care is necessary in the operation of the landfill so that it is environmentally acceptable with respect to noise, odor, dust, vector control. Flying papers and plastics must also be controlled.

7. The issue of the ultimate use of the completed landfill site is to be considered prior to the layout and designed the proposed landfill.

Hazardous waste disposal

Hazardous waste may be defined as wastes or a combination of the wastes that pose a substantial present or potential threat to human health or living organisms because:

1. Such wastes are non-degradable or persistent in nature;

2. They can be biologically magnified;

3. They may otherwise cause or tend to cause cumulative detrimental effects.

From practical standpoint, wastes are categorized into five groups. These are:

a. Radioactive substance;

b. Toxic chemicals(acids)

c. Hazardous biological wastes (hospital wastes);

d. Flammable wastes (oil);

e. Explosives (ordinance materials).

Collection, processing, treatment and disposal of hazardous wastes:

The hazardous waste is collected in sealed container to deliver it to a treatment or disposal facility. The processing of hazardous waste in undertaken for recovering useful materials and for preparing the waste for disposal. The treatment of such waste can be accomplished by physical, chemical, thermal or biological means depending upon the nature of wastes. Most hazardous waste and disposed of either near the surface or by deep burial. In some cases, they are disposed into controlled sanitary landfill sites.

High-Rise Quality Building Supplies and Services

Applying the right building supplies and implementation of high standards of engineering makes a successful high rise construction industry.

Construction industry centers by and large on the building process of infrastructures, edifices, roads, bridges, stadia, and even man-made bodies of water. Certain industry firms focus on high rise constructions.

High rise buildings have taller structures than the utmost height people would be eager to walk up. These buildings have motorized vertical haulage such as elevators and escalators. High rise buildings consist of corporate buildings, commercial infrastructures, residential condominiums, and hotels.

Detailed and efficient strategy is imperative for the success of the implementation of a construction undertaking. Project managers, construction engineers, and general contractors are the ones usually involved in this matter. These professionals are also the ones taking charge of every phase of operation of the industry.

High rise construction is a wide ranging endeavor as there several aspects that need to be considered. Some of these very important aspects are negotiating bids, applying the right building supplies, and implementation of high standards of engineering.

Thorough knowledge of cost estimation is critical. If the bid is too low, revenues may soon drop and may end in business failure. Conversely, if the bid is too high, other industry competitors will prevail.

Making use of high standards of engineering not only produces well built structures but emphasizes safety as well. For instance, the capacity of any infrastructure to survive an earthquake, whether it is of wooden framework, concrete or steel depends on whether the infrastructure was painstakingly engineered and built to defend against the sideways weight produced by the earth's shaking. Thus engineers have to thoroughly design and plan structures that can provide safety to its occupants.

The availability of superior quality building supplies is so essential to creating solid, sturdy high rise buildings.

For example, steel structures are more frequently implemented in high rise buildings. Taiwan's Taipei 101 Tower the, world's tallest building with the height of 509.2 meters above ground (The Burj Dubai will rise to 512.1 meters once completed) was put up using heavy-duty steel.

Steel has the capacity to manage remarkably heavy materials and that is why it is one of the most frequently employed materials in producing I-beams. I-beams are kinds of joist crafted from steel. They are employed as main brace trusses in buildings to make sure that an infrastructure is properly and strongly built. Other components such as aluminum are occasionally employed to assemble I-beams. Composite I-beams are also on hand, with other materials coating the outer surface of the steel I-beam to camouflage it as either wood or something else. As the name implies, I-beams' shapes look a lot like the capital letter "I".

While steel can be incredibly advantageous, concrete can offer budget friendly options. A primary benefit of concrete for high rise constructions is its natural solidity and heaviness that can withstand horizontal movement, making it a material alternative for many tall structures particularly in New York City in the past years.

Concrete along with asphalt, are typically produced combining cement with aggregates. Aggregates are an expansive classification of rough materials utilized in constructions. Gravel, sand, and stone and lightweight clay and pumice are aggregates. Portland cement is one of the popular types of cement employed for all varieties of construction projects including high rise buildings. Its main ingredients are cement cinder added with small volumes of calcium sulfate.

The right engineering and the right materials are what makes the high rise construction industry continue to go sky-high.

The Facts About Asbestos Exposure

Knowing the facts about asbestos exposure will help you to protect yourself and your loved ones. The U.S. and many other governments have compiled fact sheets and created guidelines and laws for handling and reporting asbestos exposure, as well as strict guidelines for asbestos removal and abatement. Being informed about asbestos and the dangers of asbestos exposure can help you avoid becoming a statistic.

Why Asbestos Exposure is a Problem

The danger of asbestos exposure arises from inhaling and swallowing tiny dust particles and fibers. Those particles are released when asbestos is broken up or disturbed in anyway. Once the asbestos fibers have been inhaled or swallowed, they may lodge in the lining around the lungs, heart or abdominal cavity and go unnoticed for decades.

Eventually, though, they cause scarring and cell changes that can become a malignant cancer known as mesothelioma. Even when mesothelioma does not develop, asbestosis and other asbestos related conditions can cause pain, restricted breathing and other difficulties.

How Asbestos Exposure Happens

There are many ways to be exposed to asbestos, but the most common type of asbestos exposure is occupational, or work related. Asbestos was used in the construction industry, the auto industry, on the railroads and in shipyards and in many factories that made items coated with or woven with asbestos.

When the asbestos was broken, moved, sanded, poured or otherwise manipulated, fine particles and dust was released into the air, where it was inhaled and swallowed. Family and household members of people who worked with asbestos were also often exposed to the dust when it was carried home in clothing and hair.

People who lived in the vicinity of asbestos plants may have been exposed to asbestos in the environment. According to the Agency for Toxic Substances and Disease Registry, residents who lived near asbestos plants may have been exposed to asbestos by breathing the air within a few blocks of the plant, playing in waste piles of rock near the factories and moving or handling waste rock from processing plants.

In addition, there is a significant risk of exposure to asbestos in some older buildings where asbestos laced materials were used in construction. These materials are safe as long as they are covered and/or in good condition. However, asbestos may be disturbed during renovations, demolition or when flooring, ceilings and walls become damaged.

How to Protect Yourself from Asbestos Exposure

Although the use of asbestos in new products is now heavily regulated, there are still ways that you might be exposed to asbestos. If your home was built before 1978, for instance, it likely contains many materials that were made with asbestos.

Most of these materials only become a concern when they are disturbed or start to decay. Asbestos exposure can become a significant risk if you are renovating or dealing with the aftermath of a flood, fire or other event that damaged your home. If you're not certain about materials in your home that may contain asbestos, it's best to contact your local town offices or health department to find out about having your home evaluated for asbestos and what sort of asbestos abatement regulations apply in your area.

What You Can Do If You Believe You Were Exposed to Asbestos

Mesothelioma affects thousands of people every year. Because its earliest effects are often mistaken for the symptoms of a cold, virus or flu, it's often not diagnosed until it has progressed beyond the treatable stage.

For that reason, anyone who worked or works in a job with a high risk of asbestos exposure should have regular medical checkups that include lung x-rays, and be especially watchful for respiratory ailments which may be the earliest symptoms of mesothelioma.

In addition, when asbestos exposure combines with smoking, your risk of developing lung cancer increases astronomically. If you were exposed to asbestos in the past and you smoke, quitting now can significantly reduce your chances of developing lung cancer.

Why Asbestos Exposure is a Legal Issue

Asbestos was one of the most widely used industrial minerals through the early to mid 1970s. The companies that mined, distributed and used asbestos were very aware of the danger that asbestos posed to their workers.

Instead of warning them and providing for safer handling, the industry deliberately hid those dangers from the public, their workers and the government. In doing so, they callously exposed hundreds of thousands of workers and their families to a deadly carcinogen.

Because these companies were aware of the dangers of asbestos and did nothing to warn or protect their workers intentionally, they may be legally liable for compensating people who became ill because of asbestos and their families.

If you believe that you or a family member became ill because of asbestos exposure, a law firm experienced in handling asbestos-related cases can evaluate your claim and help you get the compensation you deserve for your loss.

Asbestos Health Risks and Litigation

Asbestos is a naturally-occuring fibrous mineral of metamorpic hydrous magnesium silicate. The term "metamorphic" is used to describe a process of extreme heat and pressure which creates specific secondary patterns of minerals with new chemical and/or physical properties. As the primary rock is heated and recooled, silicate crystals align in long rows of mineral fibers, which easily separate into tiny shards thinner than a human hair. Asbestos fibers are not a health risk as long as they are undisturbed. However, when asbestos is undergoes natural weathering, or is mined and processed, the microscopic particles waft into the air and cause disease if they are inhaled.

Asbestosis occurs when an inhaled asbestos particle irritates the body's natural defence mechanisms, causing inflammation and scarring which eventually restricts lung function. Mesothelioma is a malignant tumor of the membranes surrounding the heart, lungs and abdominal cavity. Asbestos can also cause cancer of the mouth, throat, esophagus, larynx, stomach, lung and lymphoid tissue.
Asbestos exposure can also cause non-fatal illnesses such as asbestos warts, caused when asbestos fibers are lodged in the skin, causing lumps of scar tissue to form around the irritant in the same manner as they do in the lungs to cause asbestosis; pleural plaques, discrete, sometimes calcified fibrous lesions which can be seen on X-rays but are too small to cause breathing impairment; and diffuse pleural thickening, which can cause breathing impairment if it is extensive.

Due to its fire resistant properties, asbestos has been used historically for household and industrial purposes. It has been found woven into burial cloths in ancient Egypt, and Charlemagne reportedly had a tablecloth made of asbestos which he would throw into a fire to clean.

In World War II asbestos was considered so important by the War Department that it was considered a strategic material, and many American workers were exposed in the World War II boom in shipbuilding. After the war, it was widely used in the construction industry.

In modern Western society, it was used for such diverse purposes as lamp wicks, brake shoes, oven insulation, electrical hotplate wiring and home insulation, roofing and flooring. For instance, some kinds of vermiculite used in home insulation into the 1970s contained asbestos. The EPA banned this product in 1977.

When a home owner discovers asbestos in an old home, it should not be a cause for immediate panic. If the asbestos looks intact and is not pulverized, it is best to leave it alone. However, because of legal liability, schools and businesses containing asbestos usually must undergo a costly removal process, hazardous in itself because disturbing the stable asbestos product causes fibers to fill the air. Special equipment must be used to insure that the removal process does not cause health problems where non existed before.

Asbestos Lung Mesothelioma

Most industrialized nations have reduced or banned the use of asbestos for at least 30 years and now use fiberglass or woven ceramic fiber as a substitute, but since asbestos-caused disease has a latency period of up to 50 years, patients are still presenting with these illness today. Every year in America, approximately 3000 new cases of mesothelioma are diagnosed, and 550 deaths occurs due to asbestosis. According to the March 1991 Report of the Judicial Conference Ad Hoc Committee on Asbestos Litigation, asbestos exposure has caused the deaths of approximately 200,000 to 265,000 Americans.

Mesothelioma due to Asbestos Exposure

Asbestos use peaked in the United States in 1973, when 1 million tons of the material were used. The EPA attempted to institute a complete legal ban on the use of asbestos products in 1989; however, this ban was largely eviscerated by the US 5th Circuit Court of Appeals in 1991, and some restricted use of asbestos, albeit in fewer products than than before, resumed. Therefor, even today some workers are being exposed to this toxic material.

Mesothelioma Tumor

Asbestos is a serious continuing concern to the Environmental Protection Agency, and their website has detailed information on asbestos and its removal.

Concerns about the health risks of asbestos exposure date back to 1898, when the Chief Inspector of Factories of the United Kingdom reported to Parliament in his Annual Report about the "evil effects of asbestos dust". He noted that the "sharp, glass like nature of the particles" when allowed to remain suspended in the air, "have been found to be injurious, as might have been expected". In 1906 a British Parliamentary Commission confirmed the first cases of asbestos-related deaths in Bristish factories and called for improved ventilation and other safety measures. In 1918 an American insurance company produced a study showing premature deaths in the asbestos industry in the United States and in 1926 the Massachusetts Industrial Accidents Board processed the first successful compensation claim by a sick asbestos worker.

Neoplastic growth encasing right lung infiltrating interlobar fissure, and invading parietal pleura and pericardium. Hemorrhagic fluid in remainder of pleural cavity, asbestosis of lung.

Today, lawsuits claiming compensation for asbestos-related illnesses are a growth industry in the legal profession. An internet search of "mesothelioma lawyer" yields 1,910,000 results. The original manufacturers of asbestos products have long since been driven into Chapter 11 bankruptcy; plaintiffs have now turned to suing corporations with peripheral connections to asbestos products. More than 70 American corporations have filed Chapter 11 bankruptcy in due to asbestos liability claims.

Mesothelioma:Asbestos Cancer

Since the 1970's, approximateley 6% of all lawsuits filed in American courts have been asbestos-related. The lawsuits now facing the courts have been described as "an elephantine mass" by the US Supreme Court, and are expected to cost between 200 to 275 billion dollars to settle. Asbestos liability is one of the largest issues facing the global insurance industry today.

Indian woman filtering Asbestos

Most

epidemiological studies expected the number of lawsuits to peak in the 1990s, but this has not occurred, either because of the long latency period of asbestos-related diseases, or because legal action is becoming more popular among asbestos-exposed members of the public due to high-profile legal cases and widespread advertising by attorneys who specialize in such cases.

Many complaints have been made by representatives of industries facing lawsuits and the insurance companies who will be expected to pay them that the asbestos-lawsuit industry is rife with fraud, with less that half of all payouts reaching the plaintiffs. Aggressive, ambulance-chasing lawyers are said to exaggerate medical disability and coach clients on their testimony.

The group of plaintiffs includes not only ill people, but also those who have merely have a history of asbestos exposure and want compensation for potential future health risks. According to the American Academy of Acturaries Mass Tort Work Group, more than 100 million Americans have been exposed to asbestos in their workplace during the past century.

MOUNT EVEREST AND VICTORIA FALLS

Mount Everest is the tallest mountains in the world. This is the part of Himalayan Mountains. The formation of Mount Everest took place in the last few million years. India moved gradually towards Asia when the super continent of Laurasia broke up millions of years ago. The seabed which existed between the 2 plates was disintegrated and was pushed up on the Northern rim of India. These 2 plates of the crust of the earth are moving continuously, this is the reason why the Himalayas are being pushed up.

Mount Everest which is the highest mountain of the world grows by 2 inches every year. It is detected by the Satellite technology that the current height of the mountain is 29,107 feet. In the year 1852 it was recognized as the highest peak and the western name was given to it in the year 1862. The name of the Mount Everest was kept after the name of Sir George Everest who was a British surveyor. Surveyors did not agree on the height of this high mountain and therefore in 1800’s the British government thought that the height was 29,002 feet. In the year 1954 the Indian government declared the height to be 29,028 feet.

Till 1920’s the people from the western hemisphere were restricted to climb up this mountain due to some reasons. Edmund Hillary of New Zealand and Tenzing Norgay of Nepal were the first known climbers on this mountain. It was in the year 1953 that they climbed the mountain.

VICTORIA FALLS

Victoria falls are the highest waterfall in the whole world. This fall is on the Zambezi River, this river is like the border between Zimbabwe and Zambia. People consider it to be the most striking sights in the world! The fall is known as "mosi-oa-tunya" by the native people, this means "smoke that thunders”. The fall was formed due to the deep rift in the rock which lies across the path of the River Zambezi. This rift appeared by the movement of the earth. The falls are 5,545 feet across at the broadest point. There is a variation in the height of the fall from 255 feet to about 354 feet. David Livingstone is the name behind the discovery of Victoria Falls in 1855. The falls was named to honour Queen Victoria.

Mount Everest and Victoria Falls are among the most striking features of The Natural World!

Earthquake Hazard & Its Vulnerability Reduction in Guwahati City

One of the natural phenomenon, the earthquake give rise to seismic hazard to the part of the globe is very specific from the identification of seismic belt located in the earth crust. It is known by everybody that the Northeast India is seismically one of the six most active earthquake prone zones in the world the other five being are the Mexico, Taiwan, California, Japan and Turkey.   As concern to the possibility of tremor in the Northeast India, it is always responsible for the surrounding seismic belt located between the Indian and Eurasian Plate which are known as Himalayan colliding zone in the north and Burmese arc’s sliding zone in the east. Besides it, many intra_plate seismic boundaries (away from edge of the main plate margin) are also very active due to behavior of neo-tectonic activities in the Meghalaya, Mikkir Hills, foothills of Assam _ Bhutan region and its adjacent Region. From the USGS earthquake’s catalogue, all total 25 numbers of significant earthquakes occurred in this part during the last hundred and thirty nine years. It has also been found that the seismic frequencies are very irregular with the low gap which ranges approximately from 0 to 28 years. There are no major earthquake has been occurred in this region since the last 20 years. At the same time, diving margin in the Sumatra trench and colliding zone in Sichuan Province have been struck by innumerable numbers of tremors in the recent past. Out of 25 numbers of past earthquakes there were seven great tremors originated in intra-plate margins in Meghalaya and its adjacent region. The some great earthquakes occurred in this part in the year of 1869,1897,1930,1947,1949,1950,1988 which had caused of seismic hazard and flash floods in the past. The intraplate’s originated earthquakes in the Meghalaya Plateau are generally big in size and ground shaking duration is also longer along with medium focus depth of 60 to 80 kms. On the other hand, most of the earthquakes originated in the Arunachal Pradesh are the type of very shallow focus which ranges from 0 to 20 kms. These causes reveal that the whole Northeast part is a highly vulnerable and prone to earthquakes of intensity in Magnitude 8 or more. In general earthquakes at the Himalayan Colliding zones are very shallow focus and recent earthquake of Siuchuan Province of China was originated at a depth of 29 kms with the 7.9 magnitudes for which about 80,000 people had been killed. This epicenter was located around 200 kms away from east of international border of Arunachal Pradesh .The 1950 earthquake occurred in border of Assam –Arunachal Pradesh was also a shallow focused which caused disastrous in upper Assam.

          

Moreover, the longer the seismic gap has the possibility for occurrence of greater earthquake size which may caused more seismic intensity in terms of risk buffered hazards. There is a seismic gap in the Meghalaya plateau after the 1897 tremor in the Chidrang of Meghalaya where Dhudhnoi fault and many fault had crated in this area. It has known that the impact of earthquakes in the year of 1897,1930,1950,1988 were very significant as concern to the ground acceleration and its velocity. There is no doubt, that Guwahati is not a major concern to the possibility of significant earthquake in this part. The seismic hazard at mega city is controlled by active fault and other lineaments located within a distance of around 40 to 130 kilometers. The recent light size of earthquake having magnitude of 4.2 in the Richter scale had not a significant one but it’s a real concern for the short epicentral distance of around  38 kms from the heart of the city. The city is controlled basically by Shillong plateau, eastern foot hills of Himalayas,   some tectonic lineaments and faults in and around the city.

The country’s 12% of area falls in the zone V where NE India is itself 8% of the country’s spatial dimension. The other city falls in the zone –V is Srinagar and Bhuj. The cities such as Delhi, Dehradun, Jamnagar, Patna, Meerut, Amritsar, Jammu, Jalandhar are accrued in the Zone-IV. But theses cities are different from the Guwahati city from the point of surface, subsurface geology, position of subduction zone and occurrence of earthquake types.  The earthquake is always posing threat to the Dehradun city where it had occurred in the year of 1905 and 1991. From the views of tectonic earthquake and socio-economic position the Dehradun city is similar to the Guwahati city but some are not. These are population (around 5.5 lakhs), area of city (only 65 sq km), lithological uniform formation i.e large Doon Valley, topographic conditions (moderate slope and flat), safe physical infrastructures and its mass awareness etc. The Guwahati city is on the valley fill deposits having irregular thicknesses overlies the hard rock terrains along with the remnant isolated Precambrian Hills whenever the Dehradun city is on river terraces deposits mostly. The centre of Doon Valley, the Dehradun City has not been fabricated with abrupt high rise apartment. But, it is not necessary that in an earthquake prone area would not be fabricated by mega infrastructures in this millennium era if there are strong management plan and  preparedness s to mitigate the earthquake vulnerability.

In India, earthquake disaster management plan has geared up after the seismic hazards at Latur and Bhuj-Ahmadebad. In earlier, India’s disaster management plan was concentrated in the field of rescue operation and distribution of relief and rehabilitation. But, recent trend of thematic disaster management plan has been changed and it has given more importance in the technical evaluation of   quantitative pre disasters scenario in details. These assessments of scenario would definitely help to make favorable preparedness and response plan to mitigate the risk seismic hazards in any part .But this preparedness and response plan is different respective to the places or like cities. The awareness and capacity buildings are another two components in the seismic vulnerability reduction and its disaster management.

Under the GOI-UNDP risk management programmed, the seismic hazard microzonation of  38 numbers of cities over half a million population in seismic zone III, IV and V have mapped .The Guwahati city was included in this earthquake vulnerability reduction project and thereafter, seismic hazard microzonation of Guwahati city had also been completed at the 1:25,000 with the help of various relevant Government Organization. It is a tremendous milestone for the Government of Assam to achieve such type of seismic hazard mapping at Guwahati city because of first step and right direction to reach the goal of favorable preparedness and response plan in the probable seismic hazard at Guwahati city. The second milestones for Government of Assam to have a Finalized Guwahati Master Plan 2025 which will help not only to planning of Guwahti city but it will help also to develop a  Municipal GIS   in the forthcoming years. As a result it will be more positive action in carrying out the preparedness plan for mitigating earthquake disasters in the Guwahati city. The third achievement made by the GOA is to go for adoption of methodology for Rapid Visual Screening of the Buildings in Guwahati city which will help to carry out the type of buildings which may susceptible different grade of damages. The state capacity buildings at all levels are going on through the different project and schemes. The Incident Command Systems, a USAID-INDIA collaborative project running under the Ministry of Home Affairs, Government of India , which   is one of the methodology for growing capacity buildings through the training by the Assam Administrative Staff College to   grow professionalism and skilled human resources to give excellent response in the strategic time. Preparedness and responses through the practices of mock drills at different institutions is also an important component in the disaster management. It will help to create awareness amongst the peoples as well as to think favorable options to give better response in the probable disaster. These above components are the part of to harness the success of preparedness and response plan under the disaster management system. There is a need to do more work to harness the goal of success in this field of management of seismic vulnerability.

 Preparedness and response plan is different subject to the different geographical location of the cities. A preparedness and response plans of Guwahati city is not suited to the plan of Shillong city. Even also response plan of hilly stations between Shillong city and Mussoorie city will not be fitted. Because a preparedness and response plan to the probable seismic hazard is depend upon various factors such as geographical location, geomorphologic pattern, geological setup, probable size and intensity of earthquakes, soil conditions, population distributions, Municipal GIS including road networking system , availability of subsurface information, grade of social & Physical infrastructures, network communication including earthquake warnings, proportionate resources and equipments , efficient management and peoples participation etc. etc. 

The probabilistic analysis of seismic hazard in the database management system is a valuable tool in the recent trend of earthquake disaster management. The database format has emerged as a powerful simulation for the efficient disaster management due to its quick reliable decision and its accuracy assessment with the help of proper software including other technological facilities. The latest development in Remote Sensing, GIS and GPS are the only tools that it can help in application to carry out the disaster’s mapping and management with the help of integration of different thematic mappings. Development of a techno-legal regime is one of the components of vulnerability reduction project of GOI_UN; therefore, there is a need to strengthen infrastructure and updated facilities in the relevant Government departments in the field of Geology, Hydro_geology, Environmetal Engineering, Structural Engineering etc. As concern to the preparedness plan for seismic hazard  in the Guwahati city , it also need for detail Seismic hazards mapping after considering different thematic options such as  present seismic microzonation of city , land used , present population, physical infrastructures, more subsurface data including geo-hydrology etc. etc.. It may also require more strong seismographs network for monitoring and analysis of the seismic behaviors to provide availability of regular earthquake bulletin systems. Rapid Visual Screening of Buildings is also a methodology adopted by the Government of Assam to find out the building types and possibility of grade of damages in any earthquakes. These together will act as a seismic database of the city for effective mitigation in probable seismic hazard. The evaluation of quantitative seismic hazard is possible with the help of these thematic integrations. Once assessment has been made out it will help to find out the plan of calculative seismic disaster preparedness. Disaster preparedness involves many branches of Scientific Departments, Civil Defense, Police & Fires, Administration, Indian Metrological Departments, NGO,s , Medical etc. A disaster preparedness and techno legal component needs many thematic parameters of demographic, geomorphic, social and physical infrastructure including road networking, and infrastructures & facilities.

There is a frequently asked question that in spite of having an earthquake prone area, there are many metro cities built in the Japan then why not in Guwahati? To meet the query, firstly geographically and geologically it is not similar to Northeast Region. It is true that Japan is very experiencing country to face with an earthquake that had occurred frequently due to position of trench zone in the Pacific Oceanic region and received moderate to large magnitude of earthquakes. Secondly, they are the top as concern to the earthquake resistance technology in the world and they have strong seismic observation facilities. It is very strange, that they have all total 5904 numbers of seismographs including high sensitive seismographs, broadband seismographs and strong motion seismograph apart from 1500 of GPS, SLR monitoring the crustal deformations. The seismographs have been placed in surface, subsurface and also under the oceanic water. Recently they have developed the technology related with earthquake warning bulletins within two minutes of source of earthquakes. But it could not be successful in the Kawasakimachi prefecture due to arrival of S waves within 22 seconds. Yet, this bulletin will help in near future for forecasting of earthquakes. Thirdly, Government is very strict in promotion of earthquake resistance design along with standard quality of construction materials apart from availability of skilled lab ours and peoples are also well preparedness to mitigate the earthquake hazards. Fourthly, all the parts of Disaster management (Pre, post and during) plan are very advanced in the world. The 64000 elevators in Tokyo stopped running as soon as earthquake begins and equipments of control operation works automatically.

Forecasting of earthquake in terms of size, location and real time has not been fulfilled till now. But long term probability of earthquake prediction has been given on the basis of crustal deformation, interval occurrence etc. But there is a maximum probability for true prediction of earthquakes keeping view with worldwide advance researches. Till the true prediction we must have a pre-disaster plan in this city as well as to the region. The assessment of damages and destruction of buildings along with estimated danger of life respective to the size, depth, source of probable earthquake in different seismic belt of location will be fruitful measures with the help of integration of different thematic mappings in the field of seismic hazards. The identification of primary and secondary risk zone has come more prioritized to evaluate the assessment of damages in seismic hazard mapping. The vulnerable and risk zones are to be identified in the Guwahati city where there is a maximum possibility of damages at the earthquake disasters. To find out the vulnerable and risk zones it will have to consider different thematic options seismic, geology, socio-economic conditions, physical & social infrastructure, technology etc apart from mainly of seismic microzonation of city. The secondary risk and vulnerable zone is also a major criterion because earthquake proof buildings may collapse in the vulnerable zones due to liquefaction or submergence. This has occurred in the recent earthquakes in the Japan and China. Even the safe Assam Type house may come under high risk zone below the high rise apartment having necked short column in the ground floor situated on earth filling deposits. The secondary risks hazards may be broke out from the sources of  fire, landslides, road blocks by probable debris, electrical networking, telephone networking etc. The different themetic action plans may have been  prepared in the digital database format to mitigate the probable risk hazards in the city. These   preparedness plans are required urgently as concern to the  mitigation of the  probable seismic hazards in the Guwahati City .            

                      

Conclusion: 

Till the Pre disaster management plan is completed the citizens must have follow the suggestions during and after an earthquake:

§  Locate the safe open spaces near your house where no eclectic line passes. 

§  Try to stay in the plain level in the hilly areas and come away from abrupt elevation spot and go away from undercutting of soil and boulders.

§  Don't run, and move as little as possible to avoid falling debris. 

§  No need to panic if you are inside a building. 

§  Try to come out from the building where it is situated just near the wet land or on the beels. 

§  Avoid ground floors as these tend to be crushed first if a building collapses. If you can't escape, go under a table or desk to protect yourself from falling objects.

§  Big earthquakes usually have 3 phases of tremor. The first tremor is almost perceptible to humans, but it can be understood from the abnormal behavior of animals like dog, birds, snakes etc. A few seconds or minutes later it may strike the second tremor, which also humans can feel. Wait till it has stopped, then rush outside if you are near the exit, or go away from tall buildings.

§  Go away from the riverbanks of Brahmaputra, Bharalu and also from wet lands of the city. 

§  In general, second or third tremor is usually the most powerful. So, after the first tremor try to come out from the houses and stay for at least half an hour in open spaces.

§  Individual Public Buildings i.e. Schools, colleges, hospitals, markets, Offices should make the strategic plan for their better preparedness.

§  LPG plants at Amingaon, Storage at Bamunimaidam, Uzanbazar etc Noonmati Refinery and others should be made proper plan that fire could not break out at any instant.

§  As soon as you feel tremor immediately switch of the regulator of LPG if it is on.

§  Proportionate Machineries and equipments: Excavators, Bulldozers, Tipper Trucks, Hydraulic Jacks (Platform type), Hydraulic Cranes, Detectors, Pneumatic Cutters etc which are essentials in an earthquake prone city like Guwahati.

§  Before going to purchase a plot, to know the subsurface conditions of the area please consult with a Geologist first and see the Master Plan of Guwahati city and finally take the latest earthquake resistance design from a structural Engineer apart from concrete Government Norms and policy.

§  Before construction of high rise buildings first drill for taping ground water and analyzed your underground formation by a geologist apart from soil testing and others Governments Rule and Regulations.

§  Earthquake does not kill directly except liquefaction and sand craters but physical structure kill the peoples, so always keep in mind for earthquake resistance structures and accurate soil testing.

Toba Supervolcano

The trench is a seam of tectonic plates, the Burma and Sunda on the east, and the India Plate on the west. Deformation along the plate boundary, or subduction zone, resulted in the 2004 Indian Ocean earthquake and the ensuing deadly tsunami on December 26, 2004.

While our most immediate concern is for the Yellowstone Supervolcano, the Toba Supervolcano and it's historical perspective might just be of greater worldwide concern leading up to 2012. There are lessons that we can learn from these supervolcanos. What happened 74,000 years ago or threabouts in Indonesia, could be triggered again due to several pre-2012 events.

Does anyone remember December 26, 2004? Can you say TSUNAMI?

*

Location of Toba Lake

 

Bridge Interconnecting Mainland
to Toba Lake's inhabitants

The 2004 Indian Ocean earthquake was an undersea earthquake that occurred with an epicentre off the west coast of Sumatra, Indonesia. Sumatra just so happend to be where Toba lake reminds us of what happened to civilization 74,000 years agp. The 2004 earthquake triggered a series of devastating tsunamis along the coasts of most landmasses bordering the Indian Ocean, killing more than 225,000 people in eleven countries, and inundating coastal communities with waves up to 30 meters (100 feet). It was one of the deadliest natural disasters in history.


But that's nothing compared to what Toba did!
It's estimated that the Toba eruption sent so much ash into the atmosphere that is caused the last ice age that didn't end until 10,000 years ago. That would be 64,000 years of really, really COLD weather. The Toba caldera in Indonesia underwent an eruption of category 8 (or "mega-colossal") on the Volcanic Explosivity Index (VEI). This released energy equivalent to about one gigaton of TNT, which is three thousand times greater than the 1980 eruption of Mount St. Helens. The end result is that it reduced the world's human population (by 90%) to 10,000 or even a mere 1,000 breeding pairs, creating a bottleneck in human evolution according to a theory by Stanley H. Ambrose of the University of Illinois at Urbana-Champaign, in 1998.

Inhabitants Near Toba Lake

And we''re also going to witness a galactic crossing in 2012 too? Is there any good news guys?



There is scientific evidence that the recent earthquake activity in the area of the Java Trench could lead to further catastrophic shifting within a relatively short period of time, perhaps less than a decade. This threat has resulted in international agreements to establish a Tsunami warning system in place along the Indian Ocean coast. Meanwhile back here in the gold old US of A, Bush has authorized drilling another 10,000 oil wells in and around the Yellowstone supervolcano area.

Hello! This is not wise!

Did I mention that there is also a 100,000 mile crack in the earths magnetic field in the Southern Atlantic Ocean? The European Space Agency is sending three satellites in early 2009 to examine this and the over all earth's magnetic field. With 2010-2012 being the peak sun spot activity window, such outbursts of cosmic radiation is not what we need.

Bottom line here is that scientists from all over the world from many different disciplines are seeing things that are coming together between now and 2012 that says we inhabitnats better get on with coming together sooner rather than later.

Diaphragm Flexibility

In addition to supporting gravity loads and to transferring there loads to the columns and walls, roof or floor framing systems act as diaphragms that transfer the lateral forces to the LFR elements. A diaphragm is often assumed to behave like a deep beam: the deck (web) is designed for shear, and the edge framing elements or chords (flanges) are designed for the tensile and compressive forces from bending. A three dimensional analysis that takes into consideration the relative rigidities of the diaphragm and the LFR elements is required in order to obtain the most accurate distribution of the forces in these components. However, a more simple analysis is possible when simplifying assumptions are made concerning the rigidity (or, flexibility) of the diaphragm. For analysis purposes, diaphragms are typically classified as rigid, semi-rigid, and flexible. In details the classification is given in Table-1.

Flexibility Category	Diaphragm Definition
Rigid Diaphragm (F<1)	A rigid diaphragm is assumed to distribute horizontal forces to the LFR element incorporation to their relative stiffness
Semi-rigid Diaphragm( 1≤ F ≤10)	Semi-rigid and semi-flexible diaphragm are those that have significant deflection under load but which also have sufficient stiffness to distribute a portion of their load to the LFR elements in proportion to their stiffness. The action is analogous to a continuous concrete beam system of appreciable stiffness on yielding supports. The support reactions are dependent on the relative stiffness of both the diaphragm and the LFR elements
Semi-flexible Diaphragm( 10≤ F ≤70)
Flexible Diaphragm( 70≤ F ≤150)	A flexible diaphragm and a very Flexible Diaphragm are analogous to a shear deflecting continuous beam or series of beams spanning between supports. The supports are considered non-yielding, as the relative stiffness of the LFR elements compared to that of the diaphragm is large. Thus, a flexible diaphragm will distribute the lateral forces to the LFR elements on a tributary load basis.
Very Flexible Diaphragm(F >150)

In the case of rigid diaphragms, the forces are distributed to the walls and frames in proportion to their stiffness. A cast-in-place concrete floor is an example of rigid diaphragm. Diaphragm flexibility results in deformations that affect the lateral force transfer to the LFR elements. A very flexible diaphragm, such as that of plywood, will develop a large deformation compared to those of the LFR elements. In such case, the lateral force transferred to the LFR element can be based on tributary areas. The semi-rigid diaphragm, such as steel deck, is partly able to distribute the lateral forces into the LFR elements based on their relative stiffness. This situation is very similar to that of a continuous beam supported on yielding supports.

The rigidity of diaphragm can be ascertained by determining its flexibility factor (F). A slab is considered to be rigid diaphragm if it has a flexibility factor of less than one. A flexibility factor between 1 and 10 is considered to represent a semi-rigid diaphragm, and a factor greater than 10 indicate a flexible diaphragm. The flexibility factor for a concrete diaphragm is defined as:

where,

h  =  thickness of the slab, (in).

w_c =  unit weight of the concrete,( pcf)

f′_c   = compressive strength of the concrete at 28 days, (psi)

Assuming a minimum allowable slab thickness (h) equal to 3.5 in. and a unit weight of concrete (w_c) equal 90 pcf, above equation indicates a cast-in-place concrete slab to be rigid even for a compressive strength (f′_c) equal to 1500 psi. since these are extreme value, it is obvious that unless a concrete slab has large openings, it is unlikely that it will be anything but rigid. This simplifies the lateral force transfer analysis, since the forces will be distributed direct proportions to the relative stiffness of the LFR elements. A more refined analysis accounting for diaphragm flexibility would be required for semi-rigid diaphragms.