With the rapid development of Chinaâ€™s economic construction and urbanization in recent years, the scale of the city has been expanding. There are more and more high-rise and special types of modern buildings. The huge differences in the use of functions, building materials, structural forms, space, facilities, and personnel intensive between these buildings and traditional buildings pose many problems for fire safety. In the event of an accident, they can easily cause death and injury. And huge losses. Including the sudden increase in the probability of building collapse accidents, the consequences of the disaster are very serious, resulting in major casualties and property losses, and has caused adverse social impact. For example, in the United Statesâ€™ â€œ9.11â€ incident, the World Trade Center collapsed after a terrorist attack. More than 300 firefighters and thousands of people were buried in the building, shocking the world; the â€œ11.3â€ fire in Hengyang, Hunan, collapsed and the residential building collapsed. The name of the fire officers and soldiers was precious; in 2008, Fengxian, Shanghai, â€œ7.18â€ factory fire, the collapse of the plant beams resulted in 3 deaths and 9 injuries to the fire brigade. Therefore, we are earnestly studying and mastering the basic causes and general laws of the collapse of buildings, analyzing their characteristics, and studying and formulating disposal strategies to make them serve our fire fighting and rescue work.
Second, the basic causes of collapse of buildings
(A) contrary to the norms, arbitrary construction. During project design, excessive pursuit of economic benefits violated the national architectural design specifications and arbitrarily reduced the design standards. During construction, construction areas and building layers were not added without authorization, and some did not even obtain the approval of the planning department. , not designed by the design department, illegal building.
(B) illegal operations, ignore the quality. The construction unit does not strictly control the selection of construction materials and the purchase channels for private interests, cutting corners and materials, stealing materials, and adopting unqualified raw materials, concentrating on the â€œblack heart projectâ€ and â€œbean curd slag projectâ€.
(c) neglect management, potential hidden dangers. Unauthorized change of building structure and layout, unauthorized removal of the internal load-bearing structure of the building, uneven load-bearing structure, uneven force; unauthorized change of use and function of the building, the building can not meet the new use of functional requirements, become a dangerous house It does not comply with the "secondary decoration of interior decoration design fire protection code" and ignores the requirements of the nature of the use of the building, and increases the fire load inside the building.
(4) Burning and causing damage. The surface of the wood structure was ablated, weakening the cross-section of the load, and the load-bearing structure was overwhelmed. After the steel structure was heated, plastic deformation occurred. About 15 minutes after the fire broke, the load-bearing parts became soft and lost their load-bearing capacity; The internal thermal deformation and looseness of the material, and the prestressed reinforced concrete structure encounters heat, loses the pre-stress, and the bearing capacity of the structure decreases. In addition, under the high temperature conditions of fire, the mechanical properties of building materials have undergone major changes, as well as the shocks and vibrations generated by explosions inside buildings, the impact of water flow during fire extinguishing, and the sudden cooling of high-heat building components.
Third, the main features of the building collapse accident
(1) Abruptness is strong and it is difficult for people to escape. Affected by natural or human factors, building collapse accidents can occur at any time, and the accident precursors are not obvious, allowing people to escape very quickly. This suddenness makes people unable to escape in time and can easily cause heavy casualties.
(2) Facilities are damaged and it is easy to cause secondary disasters. Sudden construction collapse accidents may cause destruction of gas, power supply and other facilities inside the building, which may lead to fires. In particular, collapse of structures such as chemical installations may easily lead to chain reaction, causing toxic gas (liquid) leakage and explosion burning accidents. happened.
(3) Heavy casualties and heavy social influence. The catastrophic collapse of the building resulted in heavy casualties and significant negative social influence. In October 1963, the Veolia Reservoir accident in Italy, the human bombing in Shijiazhuang in China in 2001, the September 11th incident in the United States, the collapse of the Longmen tower crane in Shanghai CSSC Shipbuilding in 2001, and the Shanghai section of the Beijing-Shanghai high-speed railway in 2009 The collapse of the tower crane, the â€œdownside downâ€ incident in Shanghai and the collapse of the bridge in Rajasthan in India have caused panic to society and the entire world.
(4) The rescue is difficult and the combat time is long. Once a large-scale building collapse accident or natural factors such as an earthquake causes the collapse of large buildings, it often leads to more casualties and disasters, and the rescue is extremely difficult. After four days of excavation of all the victims in Hengyang, Hunan province, it was required that all rescue personnel should be prepared for continuous operations ideologically. At the same time, the rescue forces will involve the public security, medical rescue, tap water, gas, and transportation departments; due to the large number of trapped people who are buried under pressure, due to equipment restrictions, the effectiveness of rescue operations will be weakened. Therefore, post-disaster relief will be Prolonged continuous operations.
IV. Main features and basic countermeasures of rescue work in collapsed buildings
(I) Main features
1. There are many combatants and it is difficult to direct and coordinate. After the collapse of the building, in addition to the public security firefighting force, local government, tap water, power supply, gas, public security, medical rescue, local garrison and many other unit departments all need to attend the rescue operation. In addition, the top leaders who arrived at the scene did not fully understand the rescue procedures and measures. There were often people who commanded everything and everyone had the final say. However, no one could direct it and nobody said anything. The on-site identification is unclear, personnel are mixed, and the operational tasks of various functional departments are unknown, and it is difficult to form an effective synthetic rescue command system. For the firefighting force, it is also involved in commanding multiple squadrons to cooperate in the war.
2. Long rescue time and heavy logistics support. The rescue of buildings collapsed lasted for a long period of time. Many units participated in the war broke through the original security system. In addition to the need to properly ensure the protection of machinery, equipment, fuel, and food, it was necessary to do a good job in the long-term operation of machinery and equipment. Maintenance work.
3, special disaster accidents, high equipment standards. At the scene of the accident, detection equipment such as life detectors, combustible gases and toxic gas detectors, life-saving equipment such as fixed-body airbags and automatic resuscitator, and manual, mobile, and chemical cutting equipment are required.
4, little rescue experience, psychological pressure. Although through training, the officers and men of the armed forces are well aware of the procedures for handling various types of disaster accidents. However, once they come to the scene and participate in disposal operations, the gap between theory and practice will be revealed. In addition, the atmosphere of the rescue scene is tense. The fire officers and soldiers are constantly facing pressure from all sides and will have a certain influence on the decision-making and judgment of the commanders and the rescue operations of the combatants.
(b) Basic countermeasures
1. Highlight key points and actively save people. The firefighting force must take action within the first time to actively save people. The so-called first time refers to the time when the fire-fighting force receives the police and arrives at the scene. After the building collapses, the fire brigade arrives at the scene within the first time. The commanderâ€™s decision must not be delayed. He must not hesitate to wait until the arrival of the rescue force. At the same time, the fire-fighting force first followed the guiding principle of "persevering people first" in the process of handling collapsed accidents. To reach the scene of the accident, the local people must first be asked to understand the basic situation of the accident. At the same time, it is necessary to rapidly form multiple rescue teams, and to make full use of methods such as life detectors and fire dogs to accurately determine the specific location of trapped persons. According to the on-site environment and the number of rescue personnel, rescue the person in distress in the quickest time. In the process of saving people, we must follow the principle of saving the majority and saving the living. We must first make a deep and deep, easy first and then difficult. When using large-scale tools during rescue, we must proceed from the top to the bottom and from the edge to the depth to ensure the rescue. The number and quality of people.
2. Define responsibilities and coordinate actions. After the rescue forces at various levels arrive at the scene, they must promptly establish a general rescue and rescue headquarters to coordinate the coordination of various functional departments. The general command shall be served by the head of the regional government. The government shall lead the united command and shall mobilize the public security, transportation, medical, municipal, electrical and other departments and the garrison troops to jointly carry out emergency rescue operations. Public security departments set up alert areas to clean up unrelated personnel, family members, and the masses. If they need to enter the site, they must be approved by the site commander; the traffic department should evacuated the traffic; the medical department should be responsible for rescuing the wounded; the municipal department should dispatch cranes, forklifts and other machinery. On-site lifting and transport operations; power departments cut off power supply, and on-site power transmission, lighting, etc.; and the public security fire department is the main force of emergency rescue, so in the emergency rescue process, we have to take the initiative to undertake, careful planning The principle of actively reporting and promptly acting shall be carried out at the scene of emergency rescue, providing advice and suggestions for emergency rescue headquarters, and being a good adviser and assistant for the chief commander and coordinating the strength of the participating forces in all aspects in accordance with the joint action. The rescue service for the overall situation.
3, do a good job of protection, careful war. From the recent collapse accident, firefighters have suffered different degrees of injury. The scene of the collapse accident is very complicated. Secondary disasters and repeated collapses will pose threats to the officers and men participating in the war. Therefore, we must ensure that all links are implemented to prevent unnecessary casualties caused by personal protective equipment problems or improper use in rescue operations. On the premise of strengthening personal protection, actively eliminate the threat of secondary disasters and repetitive collapses to the officers and soldiers participating in the war. Those who can eliminate the dangers should be promptly eliminated. Guardianship measures must be taken if they cannot be eliminated. Personnel from different grades should take protective measures according to levels.
4, contact flow, accurate information. The complex accident scene, many of the participating teams, caused many inconveniences to the command and communication work. Therefore, it is especially important to ensure the smooth flow of information and the accuracy of information. The commander must not only understand the pre-field situation, but also grasp the situation after the arrival. In particular, he must find out the number and orientation of the personnel to be buried, the number of people who have been rescued, and the casualties. Fire-fighting forces should pay more attention to the establishment of on-site organizational structures. They should also strengthen the construction of dispatching and command centers, especially the use of technologies such as on-site image transmission, emergency road traffic control, and large-screen displays, so that local party and government leaders and senior commanders can command centers. The implementation of the command, to achieve "strategic, decisive victory", to avoid the presence of too many leaders and long-term command and personnel injuries. If there is a danger of repetitive collapse at the site, experts must be invited to assist in decision-making so as to avoid new casualties caused by improper rescue operations.
5, strengthen the equipment, special training. "For a worker to do something good, he must first sharpen his tools." To a certain extent, emergency rescue depends entirely on the equipment in our hands. The equipment determines the tactics and techniques of rescue and rescue, and determines the overall combat capability of the rescue team. The lack of corresponding special rescue and rescue equipment often leads to further deterioration of disaster accidents and unnecessary casualties for rescue workers. While the public security fire brigade is actively raising funds to purchase necessary equipment and equipment, it should guide the officers and soldiers to strengthen the familiarization and operation training of the equipment in the duty service training, carry out targeted tactical training and synthetic drills, and maximize the use of equipment and equipment. Maximum efficiency, the real realization of the best combination of man and equipment.
6. Improve the quality of commanders and combatants. Commanders at all levels should focus on learning modern fire fighting and common rescue methods, as well as emerging new situations to improve commanders' on-site resilience. Understand the operating procedures of firefighters protective equipment performance, working principle and operation methods and maintenance. Combatants should learn and master the necessary professional knowledge, such as general fire fighting methods, firefighting and rescue combat operations, and the performance and operation of the equipment and equipment of the vehicle, especially the use and maintenance of firefighters' protective equipment. In response to emergencies in disaster accidents.
V. Rescue Operation Request for Building Collapse Accident
(1) The on-site general commander shall be the fire commander. The main force of the rescue shall be undertaken by the firefighters to prevent the personnel from changing the original structure of the building too much and increasing the chance of surviving the rescue personnel. At the same time, the public security fire brigade should strengthen cooperation with other participating units and jointly implement rescue operations.
(2) Rescue workers should enhance their operational safety and should not enter the interior of the building where the building structure has apparently collapsed; they must not board the balcony, floor, roof, etc. that have been subjected to unbalanced forces; they must not venture into the unstably supported building. Ruins below.
(c) Strengthen the monitoring work on the collapsed site and prevent the recurrence of the collapse accident.
(d) In order to rescue the lives of people in distress as much as possible, at the initial stage of rescue, attention should be paid to the humanized operation. Construction machinery vehicles such as large-scale forklifts, cranes and bulldozers shall not be used to clear the site. Persons in distress should be protected from crushing, injury from falling objects, and cutting sparks and other injuries. At the same time, it is necessary to stabilize their emotions as much as possible, reduce their physical energy consumption, and implement measures such as infusion, oxygen delivery, and bandaging according to circumstances. For those who are difficult to rescue at a time, they should follow a soft landing, light elevation, and steady rescue to maximize the protection of the life of the rescued person.
(5) If flammable, explosive gas or chemical dangerous goods are leaked at the site of collapse, measures shall be taken to eliminate it quickly.
(6) Disposal of building collapse accidents generally requires long combat time. It is necessary to organize the rotation of participating personnel and do a good job of logistics support.
China Labor Insurance Network
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