Visitors take the elevator up the top floor’s observatory deck to see the breathtaking city panorama. Families and couples dine or drink champagne by the window glistening with city lights. It is the celebratory scene of US National Skyscraper Day on September 3.

This rather glamorous day commemorates the birthday of an American architect, Louis H. Sullivan also known as “father of skyscrapers” who built one of the earliest. Since then, the onset of skyscraper construction has brought about the advanced construction technology around major cities of the world.

As skyscrapers are typically approximately 40 floors (492 ft, 150 m) or taller, its construction involves impeccable framework and state-of-the-art technology for upmost safety— to support its weight and protect its habitants from natural disasters. To achieve such a feat calls for steel, the sole material relied for its unique high-strength-to-weight ratio.

Empire State Building, Landmark of the City that Never Sleeps

Originated from “Empire State”, the nickname of New York, this sparkly landmark featured in the silver screen to popular songs is the prestigious international icon of New York City. A reason why we are probably most familiar with this particular skyscraper. Located at the heart of Manhattan, the west side of Fifth Avenue, the multi-colored tower lights of the Empire State Building take the lead in decorating the city’s night skyline. Originally built as a symbol of hope during the nation struggling through the Great Depression, this famed landmark has been recorded as the tallest building in the world for 40 years in between 1931 to 1971 with its magnificent 102-story status and height reaching up to 1,454 feet (443.2 m) including its antenna.

All the while it had exceeded the height of the tallest skyscraper in the vicinity, the Chrysler Building, by as much as 204 feet. It took a tremendous amount of manpower of 3,000 workers to complete the construction in record time—as short as 13 months. The Empire State Building set the record as the tallest skyscraper in the world, a title retained until the completion of the World Trade Center in 1972.

Visitors to the 360-degree open-air observation deck on 86th and 102nd floor observatory attracts around 4 million visitors where expansive sunrise and night view of the entire city and beyond is visible, overlooking the Central Park, Hudson River, and Statue of Liberty.

Designed to withstand the building’s heavy gravitational pull and strong winds, the structural frame of the building took 57,000 tons of steel columns and beams that formed a 3-D grid throughout.

Dubai’s Burj Khalifa, the Mega Tower Overlooking the Earth

Located in the exuberant city of Dubai, this thin, needle-shaped skyscraper is gaining more and more prestige each year as millions of visitors marvel at its glamorous status of 829.8 meters (2,722 feet). This $1.5 billion-worth super scraper is currently the tallest architecture in the world since its construction in 2009. Taking five years to complete, more than 12,000 workers took part in the process for what is twice the height of Empire State Building and three times that of the Eiffel Tower in Paris.

This superstructure taking center stage in the scenes of “Mission Impossible: Ghost Protocol”(2011) where Tom Cruise pulls an edgy stunt scene moving about the walls of the building with suction gloves, gaining further worldwide stardom.

The city’s breathtaking skyline is observed  from “At the Top” deck on the 124th floor where the neighboring country, Iran’s shores can be seen during days of high visibility. In the making of this magnificent structure, 31,400 metric tons of steel rebar was used.

Lotte World Tower, Guaranteed Security among the Clouds

POSCO provided 41,000 ton-worth of high-strength steel for the construction of Lotte World Tower(Source: Tourmate)

Soaring 555 meters into the clouds, Lotte World Tower situated in Jamsil, Seoul, is the fifth tallest skyscraper built incorporating the newest cutting-edge technology. It is the home to world’s highest glass-floored observation deck creating a thrilling sensation of vertigo on the 117th to 118th floor. The observation deck reveals Seoul’s mountainous landscape afar during the day.

Leading edge construction technology from around the world was integrated into the process, and POSCO’s exclusive technology played a considerable part in the project. Thick plates (usually over 100 mm) applied in the domestic market was no more than 80 mm. However, to construct the highest building in the domestic scene, POSCO supplied 41,000 ton-worth of 120 mm thick plates and HSA800 high-strength steel. HSA800 is POSCO’s world premium product of which is highly suitable as the construction material for high-rise buildings. Even a 1mm² amount of HSA800 could support a human being weighing 80 kg (176 lb) without trouble.

Shanghai Tower, the World’s Greenest Skyscraper

Shanghai Building is spotlighted as a sustainable mega-tall tower(Source: Asiantowers)

China’s tallest, and the second tallest in the world, the Shanghai Tower is one of the recent high-rise construction recognized for its efforts in sustainable architecture. Towering 632 meters high, this China’s newest architectural invention prides on the world’s fastest elevators, highest hotel, and restaurants, as well as the tallest observation deck.

By reducing the amount of construction material needed by 25 percent, it saved approximately $58 million in construction costs. It collects rainwater and reduces wastewater for energy conservation while combining the cooling and heating power system that cuts tons from carbon footprint. Furthermore, the engineers installed 200 wind turbines at the top of the power which generates about 10 percent of the building’s electricity.

Quintessential Steel in High-rise Buildings

Use of steel delivers a range of advantages aside from stability. High-tech steel used for construction enables thinner walls making for more spacious interiors and more windows. The most crucial element is the safety aspect which steel delivers. Natural disasters pose a great threat to tall buildings from typhoons to fire hazards. As the quality of steel high-strength steel used in the construction of mega buildings is high, the resilience and ductility provide a significant advantage.

POSCO’s exclusive technology, HAS high-strength steel is an example of a material that is resistant to earthquakes. It is 1.7 times stronger than regular steel while 30 percent lighter in weight. A perfect high-strength steel that absorbs strong vibration.

In Japan, the country often hit by earthquakes, high strength steel is highly preferable for good welding and economic value. Up to 880 N/mm² in yield strength (tensile strength 1,000 N/mm²) is highly preferred.

The tense competition for reaching new heights in mega-tall buildings are still underway. Saudi Arabia’s Jeddah Tower will soon become the tallest in ranking, setting aside Burj Khalifa. Its expected height reaches above 1,000 meters, and Dubai’s Creek Tower is expected to be completed in 2021 as an observation tower rising up at 1,300 meters. With the advent of Jeddah Tower towering above 1 km, an even newer era of skyscrapers will begin where steel frames will play an even more significant part of the future’s architecture—raising efficiency in limited city spaces while creating installation artwork befitting in the creation of the Megacity.

Having discovered the architectural wonders of the world that have reached new heights through the application of steel, a tour to any of the tall buildings may now hold new meaning. Cheers to the pinnacle of human design.

Last year, California experienced the worst wildfires to date. (Source: Live Science)

It wasn’t just wildfires. The fire that broke out in Grenfell Tower in West London last June claimed 71 lives and sparked a public outcry for stricter building regulations around fire safety. The material used as cladding to wrap the outer part of the building came under scrutiny as it was extremely flammable and contributed to the rapid spread of the flames.

To prevent further disasters, architects, builders and policymakers need to reexamine the materials that go into building people’s homes, workplaces and public facilities.

Materials Matter

Steel is one of the most popular materials for construction as it is 100 percent recyclable, cost-effective and easy to work with. Moreover, World Steel Association’s Steel Construction Fact Sheet shows that steel is the most-researched and best-understood construction material available today. Its inherent characteristics and widely-available reinforcement options make steel the safest construction material for fire resistance.

eel is one of the strongest construction materials under high heat. (Source: CIC)

Fire resistance refers to the duration of time a building can withstand the load of the building, limit the passage of flames and gases and insulate the building against rising temperatures during a fire.

Steel is considered to be a fire-resistant material because it can retain all of its strength in temperatures up to 370ºC (700ºF). At 500ºC (930ºF), it loses 30 percent of its strength and at temperatures above 538ºC (1000ºF), unprotected steel loses close to half of its strength.

To put things into perspective, aluminum starts to decrease in strength when temperatures rise above 100ºC (212ºF), and at 204ºC (400ºF), aluminum loses 60 percent of its strength. Copper also loses 25 percent of its strength at 204ºC (400ºF).

Putting Materials to the Test

Darchem Engineering conducted the first-ever fire-resistance test in 1990 comparing galvanized steel, stainless steel, aluminum and fiberglass. Each material was exposed to temperatures from 1000 to 1050ºC (1832 to 1922ºF) for a period of 5 minutes. Both types of steel passed with minimal damage, while aluminum collapsed after 26 seconds, and fiberglass collapsed almost immediately.

Fire-resistance tests show that stainless steel is one of the most fire-resistant materials available. (Source: Applus)

They also conducted a 2-hour test with the same materials exposed to temperatures from 552 to 555ºC (1026 to 1032ºF). For stainless steel, the testing time was extended to 3 hours and it still had the least amount of damage out of all the materials. Galvanized steel passed the 2-hour mark, but did produce some molten zinc. Aluminum failed after 12 minutes, while fiberglass gave out in 6 minutes.

The results showed that steel, especially stainless steel, is the most fire-resistant material. However, one can never be safe enough when it comes to fire safety, and there are several ways to increase the fire resistance of steel that fall into 3 major categories.

Passive Fire Protection

Passive fire protection methods include boards, sprays and films that insulate the steel surface or structure against high temperatures. Fire protection boards are the most common type of passive fire protection as they can be customized and designed to fit the interior of the building. However, they are quite labor-intensive and costly compared to other options.

Boards are the most common types of passive fire protection. (Source: IPCOM)

Active Fire Protection

Active fire protection refers to any automatic or manual measure that can be taken to detect or fight fires. These include water sprinkler systems, alarms, smoke detectors, first responders and more. With advancements in AI and smart sensors, active fire protection will see vast improvements in the years to come and software systems will likely play a great role in fire prevention and protection.

The majority of active fire protection measures will become automated. (Source: Frontier Fire)

Intumescent fire protection

Intumescent fire protection includes paint-like substances that swell up in high temperatures and act as insulation against the heat. Typically, the intumescent substance will become 50 times thicker than its original state at about 200-250°C, well before steel undergoes any structural damage. Recently, intumescent paints have become much more prominent than passive types of fire protection as they are cost-effective, and can be applied on and off-site saving builders time and money.

Most recently, scientists and engineers from Nanyang Technological University (NTU) and national industrial developer JTC Corporation came up with a new intumescent fire protection paint called Firoshield. It is much cheaper than other types of intumescent paint and takes half the time to apply. The innovation will allow steel buildings to maintain its structural integrity for 2 hours with only 5 layers of paint, compared to the 15 layers required by other paints. 

Such innovations are expected to reinforce the safety of steel buildings, giving people more time for evacuation and limiting the spread of smoke and flames. On a final note, the fire-resistant qualities of steel should be taken into consideration not only for building frames and exteriors, but also for staircases, doors and other parts of a building that must stay intact for safe evacuations as well as for the safety of first responders.

Weather Events of 2017

2017 saw some of the worst natural disasters across the globe. The Atlantic hurricane season hit hard, and Hurricanes Harvey, Irma and Maria were especially devastating. Hurricane Harvey caused 82 direct deaths, and an estimated USD 180 billion worth of damage. Hurricane Irma swept across 9 U.S. states leaving 75 people dead and damage costs of USD 50 to 100 billion. Hurricane Maria is the worst natural disaster on record in Dominica with the official death toll at 51, but over 900 cremations have taken place in Puerto Rico following the storm.

The aftermath of Hurricane Harvey shows the importance of resistant housing. (Source: CNN)

In addition, typhoons, tornados and other weather events wreaked havoc on communities around the globe raising awareness for the need for better emergency and disaster relief systems and stronger shelters to withstand natural disasters.

Natural-Disaster-Resistant Homes

For people living in areas prone to natural disasters, a resistant home can make the difference between total property loss and a safe haven. Worldwide, home builders and buyers alike are prioritizing the home’s ability to withstand natural disasters, leading to innovative architectural feats.

The Tsunami House was built to withstand natural disasters. (Source: My Fancy House)

On Camano Island in Washington State, the “Tsunami House” is made to be a safe waterfront home, able to withstand stormy waters. The main living level was built five feet above ground, and the foundations are built on pilings capable of withstanding high-velocity waves. The lower home area was designed with breakaway walls. For both strength and aesthetic purposes, this house contains steel inside and out, with composite and galvanized exterior siding, aluminum windows, and milled finish steel materials indoors. A steel staircase structure ensures safe passage.

The SURVIV(AL) House is sustainable and has a safe room in case of hurricanes or tornadoes. (Source: Inhabitat)

Another example of a home built to survive natural disasters is the SURVIV(AL) hurricane proof house is a solar-powered home with a steel-encased safe room built to withstand the effects of extreme weather like hurricanes and tornadoes. Students from the University of Alabama created this home with a safe room that can withstand a two-by-four plank landing at 200 mph.

The Ophir home sits on a hillside with exposed steel frames to withstand earthquakes. (Source: Inhabitat)

The Ophir home was built in 2010 by a couple in New Zealand following a 6.3 magnitude earthquake that forced many people from their homes and community. The couple, however, built their home back up from scratch, but this time, made sure it would not collapse under any circumstances. Not only can the home withstand earthquakes, it is designed to maximize exposure to sunlight for sustainable living as well. A distinctive feature of the home is its exposed steel frames that support the concrete walls.

The Benefits of Building with Steel    

Steel is one of the most popular materials for construction, but its properties make it especially valuable for natural-disaster-resistant homes. Steel has a high strength to weight ratio for durability, without the heft and its associated transport costs. It requires very little maintenance, even when used as an exterior surface, and will withstand the effects of time. It is also an eco-friendly, cost-efficient material for construction.

Steel Frames are ideal for the construction of natural disaster resistant homes. (Source: Stratco)

In fact, steel can withstand forces up to 150 mph as an exterior material, without becoming damaged. Steel is also an excellent reinforcement when used with concrete, offering the stiffness, strength and ductility needed to help a building withstand damage from events like earthquakes. As part of a building’s foundation structure, steel reinforcements help anchor the foundation, and the entire home, keeping it where it belongs through wind, waves, quakes and rain.

The damage left behind by natural disasters this year show that the effects last well beyond the initial onset. While there is no such thing as a completely weather-proof building, steel can offer a great deal of security and help minimize the destructive outcomes of Mother Nature.

Cover photo courtesy of CENHS.