• Journal of the Korea Institute of Construction Safety
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• v.6 no.1
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• pp.27-32
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• 2024

In this study, based on accident cases of manned and unmanned tower cranes, the types and causes of accidents were analyzed and tower crane accident prevention measures were proposed accordingly. As a result, 'lack of communication' was commonly analyzed as the biggest cause of accidents. Therefore, in this study, we investigated domestic and international systems and laws regarding signalmen responsible for communication between tower crane operators and workers and proposed the following three improvement methods. First, the signalman system must be legally and institutionally reestablished. Second, national agencies and private organizations with expertise should create standardized training manuals and distribute them to signalman educators, and create checklists to manage educators. Third, in the case of a site using a tower crane, the employer must mandatorily deploy a signalman with professional qualifications. Lastly, the results of this study are expected to highlight the differences in accident types and causes of manned and unmanned tower cranes and the need for legal and institutional improvement in the signal system.

• Journal of the Korean Society of Safety
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• v.16 no.4
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• pp.147-152
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• 2001

The tower cranes are the very useful construction machine in the high place works. But they are very susceptible to the load balance, the wind load and the hanging load because they are the very slender structures and those center of gravity is located in the upper part. Therefore, the collapse accidents of tower one have repeatedly happened during the assemble or disassemble works. The correcting frame may has often used in order to correct the error in the setting of foundation anchors. The goal of this study is that propose the methods preventible the collapse accident of tower crane which is constructed by using the correcting frame. In order to accomplish the goal of this study, the field survey, the reference investigation and the structure analysis were performed for the collapse accident of tower crane using the correcting frame. This study result in the methods preventible the same accident.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.27-31
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• 2019

Various safety accidents occur frequently at construction sites due to poor operation of construction machines and insufficient safety facilities. Among them, safety accidents on the Tawerkrain have resulted in massive casualties and property damage. Therefore, the purpose of this study is to develop safety devices to prevent safety accidents in the Tower Crane. To this end, the existing safety device was explored and the model of the Tower Crane was constructed using Arduino. The weight of the object, the weight of the pendulum, and the distance from the center axis, as well as the equation of turning and experimentation, suggested mobile weights as a safety device to identify and resolve problems with existing safety devices. This is expected to minimize the limit on the salvage distance of the tower crane, thus providing a safer working environment away from the risk of a safety accident.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.44-45
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• 2019

Tower cranes are essential equipments that play a key role in the overall process of large-scale construction projects, as well as high-rise apartments construction projects. Tower cranes hoist various loads near and over people, working in crowded environments, sometimes in overlapping work areas, and often under the constraints of time, budget, and labor. This work system further increases the safety risks of sites with inherently hazardous workplaces. The methodology of this research was based on a comprehensive inquiry of a team of experts, including safety managers and equipment managers of major construction companies and previous literature search. Due to the limited resources available to improve safety and prevent accidents, more attention should be paid to all parties involved in factors that have been evaluated to have a significant impact on site safety due to tower crane operations.

• KIEAE Journal
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• v.7 no.6
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• pp.99-106
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• 2007

Tower crane is a large construction equipment which is extremely tall for its section when it is erected, with its high slenderness ratio, and it has a heavy load by itself due to large lifting stuff to handle. In line with the construction projects in these days which increasingly tend to become higher, larger and complex, the stuff and height subject to lifting are also getting larger and higher, which has also increased the risk of disastrous accidents. A stable foundation design thus to deal with the increasing self load becomes more important. When a typhoon Maemi swept the nation in 2003, as many as 43 tower cranes fell down or collapsed, causing a severe damage to the people and the properties. Considering such fatal damages, a technical evaluation of the stability to prevent the safety accident with the tower crane must be very crucial. Tower cranes operation in domestic construction sites, in fact, have been simply dependent on personal experience and intuition of the engineers. Particularly when it comes to the foundation design, it mostly depends on manufacturer's recommendation. The study hence was intended to develop the fundamental measures for granting the objective stability, instead of following the individual's experience only. The simulation model recommended in the study is expected to make a good commitment to achieving an effective lifting work as well as preventing the safety accident.

• Journal of the Korea Safety Management & Science
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• v.17 no.3
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• pp.115-123
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• 2015

The study conducted statistical analysis of survey on the 239 workers participating in national Tower Crane installation/dismantlement in order to identify work environment and health hazard exposure of Tower Crane workers. Consequently for work related safety status of Tower Crane workers, the number of installation/dismantlement work was the highest at 15-20 times per month, and safety equipments were not arranged at work and they felt highly anxious when boarding on the Tower Crane. Furthermore, it is found that they feel anxious working in the influence of the weather, noise, vibration, wind, the sun ray, and structure characteristic. They have very low satisfaction in the insecureness of workplace and the work environment, and recognizes that their work affect highly on the health. 81.6% of workers have experienced accident at work, the cause of accidents were mainly due to poor work environment, and the health abnormality they have experienced were mostly fatigue and concentration reduction. For job stress, job demand and conflict in relationship were the highest sections. Total 66.5% of workers complained of musculoskeletal disorder related subjective symptom, and back pain patients were the highest of all groups.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.5D
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• pp.705-717
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• 2011

The number of horizontal tower cranes, major hoisting machineries for lifting approximately 50% of entire materials in construction projects, is rapidly increasing, but a number of accidents related to the tower cranes are being continuously occurred in construction sites as well. In particular, telescoping works in the horizontal tower cranes have showed the greatest safety concerns such as falls and collapses. It is due to the fact that tasks inserting a new mast in the space made after raising telescoping cage by fluid pressure and ascending it to the required height in the telescoping works include a series of dangerous factors in safety aspects, and might cause very serious and unexpected accidents in construction sites. The primary objective of this research is to propose two conceptual models for automating the telescoping work in horizontal tower crane and conduct their technical feasibility analyses. In this study, a design concept, a position control system using hydraulic cylinders is suggested as a better alternative for automating the telescoping work. Its potential safety improvement rate compared to the conventional method is also analyzed and presented in this study.

• Journal of the Korean Society of Safety
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• v.28 no.6
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• pp.64-72
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• 2013

Construction machinery has been utilized to carry out construction works effectively. Using construction machinery enables a builder to reduce the time and the cost needed for the construction, but the fatal accident caused by it has been increased. This study is intended to identify risk magnitude of accident by kind of construction machinery through interviews with experts. Construction machineries surveyed in this research are excavator, tower crane, lift, mobile crane and forklift, those are the machinery which accident occurs more often than the other machinery. To evaluate the risk of the accidents identified, risk category was determined according to the US DOD system safety program (MIL-STD-882B) considering the risk degree and intensity. As a result, accident occurred in the process of material transport & handling was found to be the most dangerous. On the other hand, the accidents caused by the defective machinery and the poor safety gear were considered to be less dangerous relatively. The risk category by type of construction machinery suggested in this study is expected to provide the basic data in developing the safety guidance for construction project.

• Korean Journal of Construction Engineering and Management
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• v.11 no.1
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• pp.130-141
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• 2010

Poor expertise in equipment operation and installation, coupled with unpredictable natural disaster, usually directly leads to disastrous accidents of large lifting equipment such as tower cranes. For example, 52 tower cranes fell down due to the unstable support in Korea at the attack of Typhoon "Maemi" in 2003, which damaged property and caused loss of life. In high-rise construction projects, top-slewing or luffing-jib tower cranes needs checking the stability of lateral-support in addition to the bottom support such as the foundation. In this study, the optimization algorithm for lateral-support of tower cranes is conducted, which is expected to enhance the structural stability of tower cranes and save the cost in conflict with the safety.

• Journal of the Korean Society of Safety
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• v.21 no.4 s.76
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• pp.102-107
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• 2006

Construction accidents have not decreased in spite of much effort such as new work methods, education and research related to safety works. Specially, many fatal accidents happened in construction works which involve the apartment, building, school, church, hotel, hospital, bank work and the other works. These accidents are mainly caused by unanticipated risk factors. From these reasons, this study researched fatal accidents which happened in construction works during last 13 years($1992{\sim}2004$) and analyzed the input workers and a work period of construction work. According to the input workers and a work period, the results are as following. During 13years($1992{\sim}2004$), the fatal accidents, related to the construction work, were happened to the 1,977 cases. These results were occupied the 21.32% of the total industry accidents. According to the result of the construction, the fatal accident rate of a concrete form work was the highest rate of 16.24% (321 cases) and a temporary work, a steel frame work was the each rate of 12.39%(245 cases), 10.07%(199 cases). Comparing to other work types, the fatal accident rate of those three work types(concrete form work, temporary work, steel work) was represented highly. We surveyed input workers and work period of construction work site. From the result of survey, input workers of a concrete form work were occupied with 13,720. The risk rate of the work type, which was considered input workers and work period, was represented 0.3622(a steel frame work), 0.1142(a temporary work), 0.0782(a tower crane) and 0.0772(a concrete work).