Is it Possible to Protect Homes from Damaging Tornados?

While architects are continuing to make strides in designing large commercial buildings that can provide more protection from natural disasters, the powerful EF4 and EF5 strength tornados that have occurred through parts of Alabama, Missouri, and Oklahoma over the last few years have demonstrated that single family, wood-framed homes offer little protection.  Not one of those styles of homes that were in the direct path of the forceful storms survived.  Moreover a recent report from Lloyd’s of London regarding the increasing risk of tornados finds that statistically the U.S. has more tornadoes than anywhere else in the world. 

Since many of the wood-frame structures destroyed by tornados were built with the most commonly used minimum standards of the International Residential Code, some people think the standards should be raised.  Though many experts that study the destruction of tornados think it is undesirable to try and build a fully tornado-proof home.  In order to be effective, it would have to be a windowless concrete bunker. 

There are some methods that can make your home more resistant to the damage from strong winds and flying debris that occurs during tornados.  A structural engineer from Simpson Strong-Tie, which makes high-strength metal connectors, suggested in an article from MSN that to resist strong winds, “Homes must be built with what is called a ‘continuous load path.”  The goal would be to create a “series of reinforced connections that tie every element together from roof to foundation, like a chain.”  

While this could be helpful in preventing some of the damage that might occur during a tornado, FEMA recommends that you do not try and tornado-proof your whole house.  Their suggestion is for those in highly prone areas to build a “safe room”.  These rooms can be a retrofitted closet or bathroom or a newly built space in your home and should effectively protect your family against the strongest wind forces.  A safe room does not need to be very large as tornados are over quickly.  They are typically built using reinforced concrete and compared to other ideas are a relatively inexpensive solution for a homeowner.  

Conco is one of the leading commercial concrete contractors in Sacramento and has been delivering first-rate services in the area since 1959.  We are experts at creating cost-effective solutions that take advantage of the most up-to-date techniques.  Our concrete services include commercial, educational, parking and other construction development as well as public works projects and highways.

Since Conco is hard at work on the Wilshire Grand Center in L.A., which will be the tallest skyscraper in the U.S. west of the Mississippi, we thought it only fitting to do a blog series on “super tall buildings.”  Keep in mind that skyscrapers are ranked by the Council on Tall Buildings and Urban Habitat (CTBUH) and they use set criteria to designate the official height for each building.  According to the Council, “measurements are from the level of the lowest, significant, open-air, pedestrian entrance to the architectural top of the building.  This includes spires, but does not include antennae, signage, flagpoles or other functional-technical equipment.”  

For the new blog post in our series on tallest buildings in the world, we come to the fourth one, which is right here in the U.S.  The ultra-modern One World Trade Center in downtown Manhattan was designed by the renowned architect David Childs, of Skidmore, Owings and Merrill, LLP.  The building has received the designation as the tallest building in the U.S. and the fourth tallest in the world after some controversy regarding its height.  Recently the CTBUH declared that the mast on top of the building is a spire since it is a permanent part of the skyscraper’s architecture, which means the One World Trade Center is officially 1,776 ft. tall. 

The skyscraper is built with safety in mind as well as sustainability and has received LEEDS Gold certification.  According to the Port Authority of New York and New Jersey who own the building, “Its structure is designed around a strong, redundant steel frame, consisting of beams and columns. Paired with a concrete-core shear wall the redundant steel frame lends substantial rigidity and redundancy to the overall building structure while providing column-free interior spans for maximum flexibility.”  The One World Trade Center is expected to open later this year.  

Conco is a leading supplier of concrete services for the Western United States and is once again involved in doing concrete work for a major landmark project. The new Wilshire Grand Center will reshape the Los Angeles skyline as the tallest building west of the Mississippi.  As a part of the project, Conco successfully poured the largest continuous mat foundation ever done in the U.S. on February 15, 2014.

 

Third Tallest Building in the World - Mecca Royal Hotel Clock Tower

Conco is currently providing concrete services on a landmark project in downtown Los Angeles where the tallest building in the U.S. west of the Mississippi is currently being constructed.  The Wilshire Grand Center will earn a place in the record books which got us thinking about other skyscrapers.  For our blog series regarding super tall buildings, we discover that the third tallest in the world is the Abraj Al-Bait Tower, which is also known as the Mecca Royal Hotel Clock Tower. 

The Mecca Royal Hotel Clock Tower is located in Mecca, Saudi Arabia and was completed in 2010.  The Tower and the surrounding complex of six additional buildings are all owned by the government with the Tower standing well above all of the other buildings.  The official height of the tower is 1952 ft. including a 233 ft. sphere, which makes it the tallest building in Saudi Arabia and the second tallest building in the Middle East after the Burj Khalifa in Dubai.  It has occupied space up to 1,833 ft. with an observatory deck at that level.  On the building’s façade is displayed the world’s tallest and biggest clock face.

The hotel was built to accommodate the many Muslims who make yearly pilgrimages to the mosque at Makkah, which is located directly across the street.  The Tower contains a 4-story shopping mall with regional and themed Arabian items for sale and a garage that can hold over a 1,000 cars.  The Tower and the surrounding residential buildings were all a part of the King Abdul Aziz Endowment Project and are designed to be the iconic symbol of hospitality in the Holy City.

Conco is a leading supplier of concrete services for the Western United States and is once again involved in doing concrete work for a major landmark project. The new Wilshire Grand Center will reshape the Los Angeles skyline as the tallest building west of the Mississippi.  As a part of the project, Conco successfully poured the largest continuous mat foundation ever done in the U.S. on February 15, 2014.

The Earliest Cranes

A crane is a type of machine that creates a mechanical advantage for moving heavy objects that are beyond the normal capacity of a man.  It can lift and lower objects and move them horizontally to transports heavy materials from one place to another using a hoist or winder, wire chains, and sheaves (wheels or rollers).  A crane is an essential piece of equipment in the construction industry, the transportation industry, and the manufacturing industry.

The invention of the crane has had important implications on the advancement of our civilization.  It is thought that the most powerful hand crane in history could multiply the force it imparted to the operator by 632 times.  When looking at what the Egyptians accomplished with the building of the Pyramid, 50 men were utilized to move a 2.5 ton stone block, which translates to about 50 kg per person.  During the Roman Empire, a Roman crane increased the lifting capacity of a person to about 3,000 kg or 60% higher. 

Historians believe that the Ancient Greeks were the first to invent cranes in the late 600 BC and were powered by men or animals.  Archeologists have discovered distinctive cutting marks on stones from early Greek temples that prove they were lifted by cranes.  These early cranes were made of wood and enabled the Greeks to construct taller buildings. 

The Romans further advanced the development of the crane that allowed for larger and heavier weights to be lifted.  They invented cranes that were powered by groups of men or animals and used extensive pulley and rope systems.  The Roman Polyspastos crane consisted of 3 ropes and 5 pulleys which were worked by 4 men to move 3,000 kg.  

Conco is one of the leading commercial concrete contractors in Sacramento and has been delivering first-rate services in the area since 1959.  We are experts at creating cost-effective solutions that take advantage of the most up-to-date techniques.  Our concrete services include commercial, educational, parking and other construction development as well as public works projects and highways.