Construction lift accident cases

In the construction of high-rise building projects, vertical transportation often uses machinery such as building lifts. Due to improper use or management of machinery, major safety accidents often occur, and often involve mass casualties and mass casualties, which have a great impact on society. It is serious and has a major negative impact on the creation of a harmonious society. This article analyzes multiple accident cases and proposes specific reasons and countermeasures for the use and management of construction lifts and other machinery.

1 Accident case and cause analysis

Case 1; In December 2008, a construction elevator carriage fell accident occurred at a 33-story high-rise building construction site in Changsha City, Hunan Province, causing 18 People die. The elevator was rated to carry 12 people, but on the day of the accident, it actually carried 23 passengers. When it reached the 17th floor, it carried 5 people. When it was ascending from the 17th floor, the carriage suddenly fell, that is, it fell from a height of 49.3 meters. , 18 people died.

The direct cause of major fatal accidents is illegal overloading. The anti-fall safety lock of the elevator was not regularly tested and violated Article 8.1 of the national standard "Safety Regulations for Construction Elevators" (GB10055-2007), resulting in a serious lack of safety in the elevator.

Case 2: At 10:00 on November 14, 2007, a major accident occurred at a construction site in Wuxi City, Jiangsu Province. The west cage of an SCD200/200 construction elevator suddenly fell from the 11th floor. 17 workers in the cage (including the lift operator) fell to the ground with the cage, resulting in 11 deaths and 6 injuries. After analysis, the accident was caused by a mechanical and electrical failure of the lifting equipment and the failure of the safety device.

Case 3: In April 2003, a project in Ningbo had a total height of 32 floors, and the SC100/100J construction elevator had been removed to the 12th floor. The cage fell from the ceiling while it was in operation. Three people fell to the ground with the cage and died. The cage was seriously damaged.

The main cause of the accident: The analysis is that the height limit and three-phase limit limit failed. After reaching the top, the elevator drive and anti-fall gears slipped out of the rack, causing the cage to tilt outwards, and the safety above the cage The hook plate bolts were loose and broken, and the electromagnetic brake and anti-fall device were activated and the vehicle fell. On the surface, this accident was caused by the operator's carelessness and careless operation, and the roof of the cage collapsed. However, further analysis showed that this type of lift has serious safety risks because it has no counterweight device and no capping device at the top of the standard section. In addition, although the disassembly and assembly personnel and operators have certificates, they have not received systematic training. After the construction lift is partially disassembled, the upper limit limit and the three-phase limit limit must be installed as required, and tested and must be effective. During the operation, the operator must carefully observe the floor position and the operating conditions of mechanical and electrical appliances, and do not regard the upper and lower limits as automatic stopping points.

Case 4: On June 2, 2003, during the installation of a material hoist in a project in Xiaoshan, Hangzhou, a major accident occurred in which the material hoist collapsed due to serious violations of regulations and operating procedures, resulting in 3 people died. After analysis, the main reasons are: the installation unit did not obtain the special equipment manufacturing and installation license, and did not prepare a special construction plan for the installation; the installer worked without a certificate and seriously violated the regulations, and started the hanging basket without setting up temporary cables and wind ropes and other fixed facilities in time. . At the same time, the construction unit did not adequately supervise the safety of the installation process.

Case 5: On September 9, 2002, in a project in Hangzhou City, during the downsizing and disassembly operation of the building’s dual-purpose construction elevator for people and goods, the installer was working without a certificate and seriously violated regulations. The operation resulted in a major casualty accident when the construction elevator cage fell, resulting in 3 deaths and 1 serious injury.

2 The main reasons for accidents in construction lifting machinery

Through a brief analysis of the causes of the above five major safety accidents, combined with the major safety hazards that often occur at the construction site, a summary of construction lift accidents The main causes of various types of accidents are as follows.

2.1 The safety management system of each participating party is not perfect

The specific manifestation is that the construction general contractor uses contract management, the project department does not have professional management personnel, and does not carry out regular or Irregular safety inspections; the installation unit pays attention to the initial installation and disassembly, but does not pay attention to the raising operation of the construction elevator. Sometimes the raising operation is completed by non-professionals from the general contractor or the leasing unit, or the raising operation is delivered for use without acceptance. . In addition, the project supervisor did not have professional knowledge of lifting equipment, resulting in safety supervision work being unable to be implemented.

2.2 The machinery installation team is not standardized

In order to save costs, some installation and dismantling teams arbitrarily rely on formal unit qualifications and entrust unlicensed migrant workers to perform installation and disassembly. Because the installation personnel have not received systematic professional training, there are no process plans and safety technical measures for installation and disassembly, and the installation, lifting and disassembly of the equipment are not carried out in accordance with the requirements of operating procedures and product descriptions, the result is that it is extremely easy to cause accidents during installation, disassembly and use. safety incident.

2.3 The management of safety protection devices is not in place

The elevator fence boarding door and cage entrance door should have electromechanical interlocking according to the requirements of the regulations, but some machines lack it or after frequent use Failure; some elevators are equipped with mechanical door interlocking devices, which have better effects. The lift brake is prone to failure if maintenance is not strengthened, and the cleaning of the automatic gap adjustment mechanism is not in place.

2.4 The daily maintenance and management of lifts is not standardized

Who is responsible for the daily maintenance of the machinery is not clearly stated in the contract, resulting in poor on-site management of the machinery and a disconnect between equipment rental, management and use. . The hanging cage was seriously damaged and was not repaired in time; the hanging cage contained unlimited signs and operating procedures. The wire rope was not checked in time, and the broken wire was not replaced in time.

The guide wheels and pulleys were seriously worn, and the brake and electrical components were damaged and were not repaired in time.

3 Major Accident Prevention Countermeasures

3.1 Strengthen the safety management of each construction party

Construction is a high-risk operation field, so the safety of construction during construction is Control cannot only be expressed in the form of slogans, but a project leadership team with all-round functions should be established to monitor all potential safety hazards that may arise. In all aspects of construction lift installation, upgrading, and disassembly, construction general contractors, leasing, and installation units conscientiously strengthen the safety management of equipment, establish a safety responsibility system, and have emergency rescue plans for safety accidents; supervision units should strictly perform safety supervision responsibilities , with special emphasis on program control and standardized work processes.

3.2 Strengthen the management of construction machinery installation and disassembly units

The installation and disassembly units should have the corresponding qualifications and safety production licenses issued by the competent department of the Ministry of Construction, and have their qualifications permitted We undertake the installation and disassembly of machinery within the scope. Government authorities should resolutely investigate and deal with the phenomena of selling brands and engaging in affiliations that currently exist in the construction market. For some projects, the simple and extensive management model of contract management and large contract work by project managers should be fundamentally rectified. For those who do not have the necessary qualifications, Those with qualifications should be resolutely eliminated from the construction market, otherwise construction safety accidents will still happen. In addition, after the installation and disassembly unit completes the task, it shall be supervised and inspected by the local inspection and testing agency with corresponding qualifications before acceptance. The user shall then organize the leasing, installation, supervision and other relevant units to conduct acceptance inspection, or entrust inspection and testing with corresponding qualifications. The institution shall conduct acceptance inspection, and it may be put into use only after passing the acceptance inspection.

3.3 Strengthen the management of mechanical equipment by machinery users

Designate dedicated management personnel, conduct regular inspections and maintenance, and do daily operation and maintenance of lifts and other machinery; and train operators in safe operating skills Long-term, prevent workers from operating illegally.

3.5 Supervision units strengthen supervision and inspection

Strictly review the manufacturing licenses, product certificates, manufacturing supervision and inspection certificates, and filing certification documents for construction lifts and other mechanical equipment; review installation units, usage The unit’s qualification certificate, safety production license and special operation qualification certificate of special operators; review the special construction plan for installation and disassembly projects; supervise whether the installation unit conscientiously implements the special construction plans and safe operating procedures for installation and disassembly projects; supervise and inspect the construction The use of lifts and other machinery;

Construction lifts and material hoists are currently the main vertical transportation equipment in construction. Due to the high risks and many management problems, the "Construction Safety Inspection Standards" ( JGJ59-99) has included it in the special inspection content and requires all units to manage it carefully. However, accidents still occur from time to time in various places. Failure to comply with laws and regulations is the fundamental reason for casualties in construction elevators. This series of accidents highlighted the imperfection of the safety production supervision and management mechanism in the construction industry, the failure to implement the safety production responsibility system, and the weak awareness of safety production among managers and workers who are responsible for safety production during the project construction process. Therefore, it is necessary to establish a liability investigation system, which not only requires those responsible for illegal acts to be held criminally responsible in accordance with the law, but also holds corporate leaders with management responsibilities to be held administratively accountable in accordance with the law. Only through strict regulations and implementation of responsibilities can casualties and accidents be effectively controlled. In addition, construction lifts are stereotyped equipment. The country has "Construction Lift Standards" on how to use and inspect them. If all units strictly follow these standards, most accidents can be avoided. Finally, the safety awareness and skills education and training and various inspections of construction machinery managers and operators must not be a mere formality, and it is also necessary to effectively strengthen management.