• Explosives and Blasting
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• v.26 no.2
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• pp.52-63
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• 2008

Recently the demand of demolition for the unnecessary cylindrical silo structure is increasing due to deterioration and unsatisfactory functional conditions and the issue of demolition is becoming a major highlight. This case study introduced the explosive demolition of the cylindrical silo structure by felling method. The results of explosive demolition conducted on cylindrical silo structure using the felling method show, A silo had collapsed precisely according to estimated direction but in case of B silo there was a minor difference. The lower colunms and ring girder support was designed to the hinge line but in reality the lower colunms of the silo did not do its structural support role and only the ring girder support did its role successfully. As for the impact vibration, most of the measurements were within the estimated range.

• International Journal of High-Rise Buildings
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• v.3 no.4
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• pp.243-254
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• 2014

In this study, a demolition analysis code using the adaptively shifted integration (ASI)-Gauss technique, which describes structural member fracture by shifting the numerical integration point to an appropriate position and simultaneously releasing the sectional forces in the element, is developed. The code was verified and validated by comparing the predicted results with those of several experiments. A demolition planning tool utilizing the concept of a key element index, which explicitly indicates the contribution of each structural column to the vertical load capacity of the structure, is also develped. Two methods of selecting specific columns to efficiently demolish the whole structure are demonstrated: selecting the columns from the largest index value and from the smallest index value. The demolition results are confirmed numerically by conducting collapse analyses using the ASI-Gauss technique. The numerical results suggest that to achieve a successful demolition, a group of columns with the largest key element index values should be selected when explosives are ignited in a simultaneous blast, whereas those with the smallest should be selected when explosives are ignited in a sequence, with a final blast set on a column with large index value.

• Explosives and Blasting
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• v.40 no.3
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• pp.54-65
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• 2022

Recently, the demand for the dismantling of large-scale industrial structures is increasing, and the construction of restoring the dismantled industrial to their original natural environment is underway. This case was an application of the explosive demolition method to the demolition of a large section turbine foundation structure which structural obsolescence and failure to meet functional requirements. As a result of the explosive demolition, the fracture condition of the turbine foundation was satisfactory, and the explosive demolition was completed without causing any damage to the surrounding facilities.

• Korean Journal of Construction Engineering and Management
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• v.14 no.1
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• pp.124-132
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• 2013

An influx of the population to the city has soared due to industrialization. As times go by, cities become densely populated so Korean government started to construct a number of buildings including apartment housings. Because they have become functionally, structurally, esthetically deteriorated over the past two decades. some improvements are needed. There are mainly two ways to improve old buildings: remodeling and reconstruction. Between the two, the first one is more popular as it is less time-consuming and more eco-friendly. Demolition work comes first for both of them and it should not give negative effects since it is regarded as a CP(Critical path) in the overall process. For this reason, a thorough construction management must be done. The reality, however, demolition is managed by the construction manager's experiences and decisions. If the key factor of demolition which is the planning of manpower and machine equipment, is determined by unscientific and subjective judgments, its period and risk also will increase. In particular, eco-friendly demolition can be more risky because it's been rarely conducted. Therefore, scientific and objective ways of demolition management are needed. In this context, this paper aims at analyzing productivity in each process of demolition focusing on manpower and machinery equipment which are the main parts of demolition assuming that the demands of eco-friendly remodeling demolition projects will be increasing. At the same time, by estimating working period through the output, this paper would be helpful to set up the plans for overall project in earlier stage.

• Explosives and Blasting
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• v.28 no.2
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• pp.99-107
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• 2010

Domestic explosive demolition techniques have been developed and applied for low-rise structures up to now. However, the demand for the development of those techniques that can be applied economically, safely and environment-friendly rapidly increases because the old high-rise RC rahmen structures that were built since around 1970s are now required to rebuild. As a result, element technologies of explosive demolition for low-rise structures were applied to take advantage of technology in high-rise structures that performed application testing at Chungang Department demolition field in Daejeon city. It could judge elements technology establishment for high-rise structure demolition and field application and suggest the improvements when the problems occurred to develop High-rise building demolition techniques for method of protection a field test and the dust reduction test. The water cannon test was applied to reduce the dust site and the drilling tests are performed to select the best components for explosives demolition elements techniques of the reliability. This paper shows that we have the ability to remove a high-rise building using environmentally friendly safe and economical explosives demolition method. It would contribute to prevent a foreign company from entering the domestic market and should contribute to acquire competitiveness of domestic demolition industry.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.3
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• pp.1007-1015
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• 2014

The importance of construction waste reusing and recycling is becoming increasingly large because the demolition industry is in current trend to pursue for sustainable growth. As the considering situation of the domestic housing construction and existing house, a scale of demolition industry is expected to be increased continuously. But the related cost regulations that are used in tendering in the demolition industry are insufficient, also the computer system for estimating the demolition costs have not been developed yet. Therefore, in this study suggests man-hours of 21EA items which are utilized to estimate demolition cost and work rate of $1.0m^3$ breaker which is used mostly in domestic demolition industry after analyzing a case study for deconstruction works. The computer system is developed for the estimating demolition cost easily, which are including five modules such as a project information, a unit cost management, a standard unit cost table, a bill of quantity, and a reporting system. This computer system is possible to apply for estimating cost of both mechanical demolition and blasting demolition. The biggest advantage of this system is to estimate cost to utilize standard WBS which is linked with standard unit table and each DB. This can help unskilled users use easily for it.

• Explosives and Blasting
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• v.25 no.2
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• pp.47-60
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• 2007

The blast demolition technology has been used to demolish various industrial facilities and tall buildings since 1950s in the advanced countries such as USA and U.K. It is now considered as one of safe demolition methods in the above countries. In Korea, several companies have tried to introduce blast demolition technology in the early days of the 1990s. However, this technology is still at the beginning stage and not fully adopted due to situation of avoiding technology transfer by overseas technical tie-up companies, lack of objects to be demolished and low level recognition on blast demolition. This technology shall be considered as a cutting edge technology to be applicable to demolition of skyscrapers, various industrial structures and factory buildings in the near future. Blast demolition of a pier structure was carried out under the site condition where there were already the constructed 2 pier structures of up and down line which had safety problems in an expressway construction project. The pier structures need to be demolished and reconstructed for a short period of time in consideration of the construction work process to be followed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.627-634
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• 2006

Now, in a domestic country, the rebuilding and redevelopment of existing houses has been rapidly increasing with an economic growth and the improvement of living condition. As a result of that, a lot of C&D waste has been also produced. Nevertheless, it is not easy to find the research results for appropriate treatment and management of C&D waste in domestic. Therefore this study suggests the optimum deconstruction management system for minimizing construction waste and increasing reuse or recycle rate of material different from traditional demolition. The system makes it possible to plan and manage in advance quantity of C&D waste, demolition methods of each structural elements and application methods of produced C&D waste through an integrated and computerized system. The purpose of the system is ultimately to contribute to minimizing environmental damages and reducing construction waste quantity of a country. This system is largely composed of four modules such as planning of preliminary demolition survey, estimating of demolition quantity, planning of demolition schedule and planning of construction waste management and each module can be also used individually according to the purpose of a user.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.5
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• pp.251-258
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• 2018

In construction site, conventional methods such as jackhammer or explosive methods(dynamite) have been often used for the demolition of structures. Use of those methods are more carefully treated in environmentally and historically sensitive area. For those reasons, use of Soundless Chemical Demolition Agent(SCDA) is getting the spotlight. The SCDA is a powder which has expansive strength when it is mixed with water. In these Characteristics, SCDA can destroy the concrete or rock as it is poured into boreholes of the concrete or rock structures. However, there is no industrial standard for the use of SCDA effectively yet. In this study, experimental study to measure the expansive pressure was conducted depending on various boundary conditions such as waterproof, length of the steel pipe, submerged of steel pipe. Furthermore, computational analysis using damage plasticity model to predict the minimum required pressure of the SCDA for the concrete demolition depending on spacing between holes(k-factor) and compressive strength of the concrete was conducted. Obtained results indicates that water heat dissipation with submerged steel pipe shows the stable pressure for measuring the SCDA and hole distance(k-factor) is the most important factor for crack initiation of concrete.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.1959-1965
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• 2023

The objective of this study was the establishment of clearance method that can ensure radiological safety and reasonably minimize radioactive waste when demolishing contaminated buildings at KRR-1&2. By reviewing Korean and international laws related to decommissioning, the method for clearance of contaminated buildings presented in this study is to first decontaminate the building and then conduct a radiological safety assessment, such as measuring residual radioactivity, to determine whether the radiation dose criteria for clearance are satisfied. The measurement results meet the radiation dose criteria, the contaminated buildings are regarded as clearance and can be converted into the general buildings. The demolition of the cleared buildings is carried out using conventional demolition methods. The waste generated during the demolition is classified as general construction waste and is disposed of according to relevant laws. The proposed method significantly optimized the number of samples analyzed and reduced the time and cost associated with the decommissioning. The established method will be applied to the ongoing decommissioning of contaminated buildings at KRR-1&2, and its application will be verified by regulatory bodies. The study suggests that this method could be used for the decommissioning of contaminated buildings at other Korean nuclear facilities in the future.