• Korean Journal of Construction Engineering and Management
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• v.14 no.2
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• pp.96-107
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• 2013

Tower crane hoisting plan is one of the key element for the success of entire High-Rise Building construction. Hoisting time is the basic factor to appropriate hoisting plan which need to the hoisting load estimate and tower crane selection. With this reason, accurate hoisting time is needed to the proper hoisting plan. The current hoisting time estimation for High-Rise Building focus on the hoisting cycle time estimation with historical data. However, this method underestimated the external influences like environmental factor. Thus, this paper aims to develop the hoisting time estimation model with discrete event simulation which include the wind influences with certain height. According to the simulation result, the hoisting time which applied wind influence is increasing with height growth. Because of the high speed wind, the upper area of building has more operation delay time than the mechanical operation time. Seoul, the research area, has the most fastest wind speed on April and the least on October. Due to these differences of wind speed, the hoisting time is estimated with significant differences between April and October. This hosting time estimation model would be used for estimating the influence of wind. Moreover, this could apply to make the realistic hoisting plan.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.9
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• pp.1461-1467
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• 2001

This paper proposes a new approach for the ant-swing control of overhead cranes. The proposed control consists of a model-based anti-swing control scheme and a practical path planning scheme. The anti-swing control scheme is designed based on the Lyapunov stability theorem; the proposed control does not require the usual constraints of small load mass, small load swing, slow hoisting speed, and small hoisting distance, but guarantees asymptotic stability while keeping all internal signals bounded. The path planning scheme is designed based on the concepts of minimum-time control and anti-swing control; the proposed path planning generates near-minimum-time trajectories independently of hoisting speed and distance. The effectiveness of the proposed control is shown by computer simulation.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.472-475
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• 2004

The objective of this study is to develope reasonably accurate prediction models to assess hoisting times of tower cranes in the high-rise building construction. The efficient use of the tower crane is critical to achieving the Planned floor cycle time. This research describes the derivation of mathematical models to predict the hoisting times in using a tower crane. 28 factors such as nature of load, characteristics of tower cranes, hoisting movements, operation of cranes, weather conditions and so on is considered to influence hoisting times. In order to develop the predicting hoisting times Correctly, it is divided hoisting upward and downward. Then multiple regression models for predicting supply and return hoisting times have been built up separately.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.64-65
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• 2016

According to the recent increase in the height of supertall buildings, construction lift became one of most important equipment for vertical transportation of resources. However, increase in lifting load during peak time in which the resources are concentrated often causes a risk of construction delay. This study suggests a concept of Double-Cage construction lift, which is a lift with two cages attached together allowing transportation of resources on two consecutive work floors simultaneously. The aim of this study is to present a simulation model suitable for calculating hoisting time of Double-Cage construction lift. The proposed model is expected to be utilized when applying Double-cage construction lift for its efficient operation and management.

• Journal of architectural history
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• v.30 no.5
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• pp.7-16
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• 2021

According to 「Hwangnyongsa Temple Central Column Record」 among the remaining documents, under reconstruction the pagoda of Hwangnyongsa&s 9th floor was completed in July 872 on the lunar calendar. At that time, King Kyeongmun worried about sarira under its central column, saying the central column does not move, and then He ordered to lift the central column. So his servants lifted it on November 6th 872 and checked the sarira and put it back on November 25th on the lunar calendar. 「Hwangnyongsa Temple Central Column Record」 did not document how to lift the central column which is tens of meters. therefore, this study inferred the way the central column of the pagoda of Hwangnyongsa was lifted in 872, left as a mystery. For that, this study set various hypotheses and it researched and analyzed hoisting technique that is a way to lift the pagoda of Hwangnyongsa and a column. In conclusion, this study inferred the most suitable hoisting technique for the pagoda of Hwangnyongsa at that time, based on the research and analysis of each chapter.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.221-225
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• 2015

To hoist construction workers to their working space is directly related to the productivity of building construction since hoisting tasks are carried out during the working time. In order to reduce hoisting time in the condition that the number of construction lift-cars is limited, various types of the lift-cars group operation plans such as zoning and sky-lobby have been applied. However, previous researches on them cannot be compared in the performance due to their methodological limitation, discrete-event simulation methods, and cannot be find better solution to increase the performance. Therefore, this research proposed the simulation-based optimization model combining the agent-based simulation method to the scatter search optimization methods. Using the proposed model, this paper carried out the comparison analysis on the performance of typical operation plans and also optimize an operation plans by controlling the service range of lift-cars, the size and number of service zones. In this case study, it is verified that better alternatives than typical operation plans can be exists and it is possible to increase the productivity of building construction.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.192-200
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• 2017

With the acceleration of construction industrialization, the buildings that China has adopted the construction of industrialization technology are increasing day by day, and Precast Concrete (PC) Structure technology is one of the main technologies of construction industrialization. Compared with the traditional cast-in-place concrete structure, PC structure is more conducive to shorten the construction period, reduce the number of construction workers and the site construction waste. Nevertheless, PC structure improves the requirements of hoisting machinery in the construction site, and the lay-out and selection of hoisting machinery become an important factor influencing the construction cost. The paper regards the typical tower crane in China as the research object, and establishes the time optimization model for the lifting scheme. The influence of the different precast rate on the selection of the tower crane is analyzed. This paper obtains the time variation of the tower crane under different precast rate, provides a theoretical basis for the design of precast concrete structures under the influence of assembly construction, and lays the foundation for the selection of tower crane under the precast rate.

• Journal of the Korea Institute of Construction Safety
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• v.2 no.1
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• pp.1-8
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• 2019

Recently, as development of building construction technology, height of building continues increase. But, there is no clear ground of service life of tower crane. So, accident in the tower crane continues to occur. In addition to Korea, there is no clear ground for the serive life of tower cranes overseas. For this reason, this study aims to establish the maximum service life of tower crane. Accidents in tower cranes continues to increase, and the cause of the accident is that there are no ground of limitations for service life of tower cranes. Therefore, in this study, the maximum service life of the tower crane was calculated by using the information of the hoisting case of the tower crane to limit the model year of the tower crane. The results of this study are as follows; As the number and time of the hoisting work increases, the maximum service life of the tower crane decreases. In addition, since this study refers to European standards, it is necessary to establish standards for domestic situations. Result of this study, we expect decrease accidents in tower crane. And it is expected that the service life of tower crane will be more clear if this study is developed.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.1
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• pp.95-102
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• 2018

This paper proposes a dual lifting and its cooperative control system with two different kinds of floating cranes. The Mega-erection and Giga-erection in the ship building are used to handle heavier and wider blocks and modules as ships and off-shore platforms are enlarged. However, there is no equipment to handle such Tera-blocks. In order to overcome the limit on performance of existing floating cranes, the dual lifting is proposed in this research. In the dual lifting, two floating cranes are well-coordinated to add up the lift capabilities of both cranes without any loss such that virtually a single crane is lifting, maneuvering and unloading. Two main constraints for the dual lifting are as follows: First, two barges of floating cranes should be constrained as a rigid body not to cause a relative motion between two barges and main hooks of the two cranes should be controlled as main hooks of a single crane. In order words, it is necessary to develop the cooperative control of two floating cranes in order to sustain a center of gravity of the module and minimize the tilting angle during the lifting and unloading by the two floating cranes. Two floating cranes are handled as a master-slave system. The master crane is able to gather information about all working conditions and make a decision to control the individual hook speed, which communicates the slave crane by TCP/IP. The developed control system has been embedded in the real floating crane systems and the dual lifting has been demonstrated five times at SHI shipyard in 2015. The moving angles of the lifting module are analyzed and verified to be suitable for hoisting control. It is verified that the dual lifting can be applied for many heavier and wider blocks and modules to shorten the construction time of ships and off-shore platforms.

• Journal of Advanced Research in Ocean Engineering
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• v.1 no.2
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• pp.85-93
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• 2015

The nonlinear time-domain analysis method was implemented to carry out a series of integrated simulations for a deep-water crane vessel system composed of four sub components, including a floating vessel, lifted equipment, hoisting cable and dynamic positioning (hereinafter DP) system. The analysis of the coupled dynamics consists of the crane vessel and equipment connected using the crane wire, and the DP is modeled according to the wind, wave and current conditions. The DP systems were numerically implemented using a classical PD feedback controller, and various simulations of the deepwater installation were conducted using different conditions in order to evaluate the global performance of the floating crane vessel combined with the DP system.