Abstract There have been many catastrophic incidents involving fire throughout history with countless of lives lost and billions of dollars’ worth of damages. The lessons learned from these incidents have led to changes in the way we plan and how we build high-rise structures. These changes evolve into codes and building standards with people’s safety in mind. Early building construction laws were enacted to prevent building collapses as early as the Roman Empire. Laws were passed that limited the height of buildings, first to 70ft and then to 60ft.
Later in history, laws were passed to prevent fires and preventing its spread; in early North American cities, structures were built in close proximity to one another and often construction started before proper building codes were in place. (Cote) After the Great Chicago Fire of 1871, tall buildings were built with safety in mind. The National Board of Fire Underwriters (NBFU) and now the American Insurance Services Group, organized in 1866, began to emphasize safe building construction, the prevention of fire spread, improvements of water supplies and fire departments.
As a result, buildings would be built of concrete and steel. In 1906, the NBFU wrote that “San Francisco has violated all underwriting tradition”; although the city had concrete and steel buildings, most of the structures consisted of wood shacks. Following the damage of the San Francisco fire, the information gathered was used for the basis of early fire protection and building codes. (Cote) There have been many factors that have shaped modern building codes. The development of the insurance company and the concept of mitigating risks has been a part of building codes for years.
As social organizations were created to improve building conditions, building codes were enacted to meet those needs. Chicago was the perfect location; it is near waterways. The city had to build quickly so they built with wood. It was quick, cheap and it was easy. There was plenty of wood coming through the city. Many of the buildings although they had a hard shell made of masonry but the insides were made out of wood. Since the city was growing, quickly there was no proper planning on how to correctly build a structure and there were no rules.
There were homes next to lumberyards next to businesses’ and by 1871; Chicago was the fastest growing city in the world. (The University of Chicago Library, 2009) The swamps by Lake Michigan made visionaries into millionaires. The summer of 1871, was extremely dry and by October, people were suffering from a drought. (Billington) On the evening of October 8, 1871 on the city’s west side, a small fire erupted at a barn owned by Catherine and Patrick O’Leary. The night operator sent a telegraph to firefighters; but failed to inform the firehouse closest to the fire.
By the time firefighters reached the O’Leary barn, about 20 minutes after the first alarm, the fire had spread throughout the block. (Bales, 2004) The winds pushed the fire north and east by the banks of the river. Most people did not expect the fire to cross the Chicago River but by 11:30 PM, the river was in flames. The river was lined by wood buildings, wood ships, and the water itself had an oily residue due to pollutants. After jumping the river, the fire tore through the city’s business district.
The heat of the fire helped it generate its own wind by sucking in oxygen while the rising flames spread upwards like a fiery tornado. Around 2:30 am, the fire jumps the river once again sending fiery ambers into the city’s North District towards the city’s only water pump station. The wooden roof ignites and eventually collapses cutting all water supplies to the city. Nearly 30 hours after it began, rain extinguished what was left of the city. The fire burned 4 square miles destroying banks, department stores, hotels, and offices.
According to Bales, 2002, three hundred people perished and 100,000 were left homeless. Years after the fire, the city became conscious about pre-fire planning and they established new building codes. (The University of Chicago Library, 2009) In early 1906, San Francisco’s downtown area consisted of some steel and concrete buildings but most of the city’s construction consisted of wood. On an April morning, the city experienced a massive earthquake that destroyed 28,000 buildings of which 24, 678 were wood structures and killing 3000 people.
There were 3,168 brick buildings lost. (US Department of the Interior, 2011) The fires that burned for the next four days and nights caused the majority of damage. The earthquake damaged much of the water mains and firefighters did not have many resources to fight the fires. (Schussler, 1906) People were setting their houses on fire due to insurance companies not paying them for damaged caused by the earthquake but paying for damages caused by the fires. (Wildman, 1906). Not surprisingly, the earthquake and subsequent fires lead to changes in building codes.
New constructions would have to be built with reinforced concrete, which politicians had previously blocked. Buildings would have to be steel framed and able to withstand lateral wind forces of 30 pounds per square foot. That number would later be reduced to 15 pounds per square foot in 1920. (University at Buffalo, 2008) “The destruction of the World Trade Center (WTC) on September 11, 2001 was not only the largest mass murder in U. S. history but also a big surprise for the structural engineering profession. No experienced structural engineer watching the attack expected the WTC towers to collapse.
No skyscraper has ever before collapsed due to ? re. (Bazant, 2007, p. 308)” One of the most important events of New York City in the 1960’s was the construction of the World trade center. The design and construction of the towers took years and the effort of thousands of people. A project of that size created challenges that demanded the use of dramatic new engineering concepts. Final plans called for a complex of low-level buildings surrounding two 1350-foot towers. Their great height was made possible by the use of load bearing walls.
(PBS, 2000-2001) Extremely tall buildings were inefficient since structural support and elevators took up huge amounts of interior space. The exterior walls were design to hold much of the weight of the towers and as well as all of the wind loads. The only internal support for the buildings was a central support of towers. Elevators were placed in the shafts that were formed by the columns. These engineering considerations determined the towers basic design. (PBS, 2000-2001) The catastrophic events of September 11, 2001, lead to the adaptation of new building codes by the International Code Council (ICC).
Studies were conducted by numerous agencies and recommendations were made. (Mcallister, 2002) New codes call for numerous changes in building designs, construction, how the buildings would need to be maintained, more dependable fire proofing, and tougher structures among other things. Bigger exits would give people a better chance of exiting a structure in case of fire or major disaster. (Mangels, 2011) “The study’s major finding is that the collapse was the result of a hydrocarbon fire and the impact of the jetliners, not structural deficiencies.
The report’s recommendations include building redundancy and robustness into structural framing systems so that alternative paths or additional capacities are available to transmit loads when building damage occurs. Fireproofing should adhere to steel members under conditions that deform them. The connection performance of critical components in structural frames under impact loads and during fires must be quantified to improve performance and building sprinkler systems must have a reliable, redundant water supply.
The report also recommends that egress systems currently in use be evaluated for redundancy and robustness in providing adequate evacuation capacity when building damage occurs. Among the issues to consider are transfer floors, stair spacing and locations, and the impact resistance of stairwell enclosures. (Nicholson, 2002)” The ICC adopted several recommendations years later to improve on building codes and construction. The following were some of the recommendations but not limited to. * Elevators with fortified walls that firefighters can utilize during an emergency to evacuate personnel.
They must be synchronized with the fire alarm system and all elevator hoist ways must be protected with fire suppression systems. The elevators must be easily identifiable and must have key-recall switches. The emergency controls in elevator cars must be protected and they must have recall switches. * A minimum of three stairwells per floor with impact resistant walls; the stairs must be at least 66in wide to accommodate rescue personnel, evacuees, and 30-foot separation between stairs to prevent a single accident from destroying all of them.
* Sprinkler systems must cover all floors and have a backup water supply in case the main supply fails. * Buildings must have shatterproof windows laminates with clear film or backed up with Kevlar to prevent flying debris in case of explosion * Requiring evacuations plans: It was recommended that building owners be responsible for organizing and executing emergency plans for all high-rise buildings. The fire hazard emergency plan should address other hazards affecting life safety regardless of whether the hazard is initiated by accident, pre-meditated actions, or natural causes.
* Delivery areas must be protected and away from any critical building areas. * Emergency voice communication must be provided. Building must have radio amplifiers so that emergency personnel can communicate inside buildings and avoid “dead spots”. (Rodriguez, 2011) “ For such exit stair arrangements, new provisions will require that approved exit or directional signs mark horizontal components of egress paths within exit enclosures where the continuation of the egress path is not obvious. This requirement is intended to apply to both new and existing facilities.
(Puchovsky, 2007)” In closing, natural disasters or accidents causing fires will always be a part of life. People must take what they have learn from past incidents, engineers and builders must follow building codes and proper building construction practices to keep future occupants safe. They must look for ways to make tall building and structures safer for occupants should an accident occur. Resources Bales, R. F. (2002). The Great Chicago Fire and the myth of Mrs. O'Leary's cow. Jefferson, North Carolina: McFarland and Company, Inc. , Publishers. Bales, R. F. (2004, May 12).
Did the cow do it? a new look at the great Chicago fire. What do we know about the great Chicago fire. Retrieved from http://www. thechicagofire. com Bazant, Z. P. (2007). Mechanics of Progressive Collapse: Learning from World Trade Center and Demolitions. Journal of Engineering Mechanics © ASCE, 308. Billington, J. H. (n. d. ). The Library of Congress. Retrieved from America's Story from America's Library : http://www. americaslibrary. gov/jb/recon/jb_recon_chicago_1. html Cote, A. E. (n. d. ). Codes and Standards for the Built Environment. NFPA. Retrieved from http://www. nfpa.
org/assets/files/pdf/codesfph. pdf Mangels, J. (2011, August 14). Decade after 9/11 World Trade Center attacks, skyscraper safety improving. Retrieved from www. cleveland. com: http://www. cleveland. com/science/index. ssf/2011/08/a_decade_after_the_911_attacks. html Mcallister, T. (2002). FEMA: World Trade Center: Building Performance Study. Data Collection, Preliminary Observations and Recommendations. New York, New York: Greenhorn and O'Mara Inc. Nicholson, J. (2002). Joining the search: NIST’S investigation may become the impetus for code revision. NFPA Journal, 48. Retrieved from