• Explosives and Blasting
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• v.19 no.1
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• pp.11-18
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• 2001

This is a case history on design and cnostruction of tunnel for under passing an underground transformer substation. The original construction plan was cut & cover method to avoid blasting vibrations and displacements of facilities during the construction stages. But this plan was changed to tunnel because of the difficulties from construction period, cost and the required relocation site. As a results of tunnel construction, the relocation of transformer substation and replacements of transmission cables were not necessary. Therefore about 10 months of construction period and 3.5 billion wonts of construction cost were saved. Additionally, quantitative criterion for blasting was provided through the results of blasting vibration analysis.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.169-170
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• 2020

Occupational Safety and Health Management Cost, used to protect workers in Korean construction worksites and to create safe working environments, is a legally managed expense item. As this cost item is grounded on the Occupational Safety and Health Act, it is always implemented. However, because there is a ceiling on its rates, insufficient amounts of Safety Management Costs are often allocated to worksites, with the money not being used to areas essential to worker safety. As such, the current study raises the need to develop a set of standards to enable some items under the Occupational Safety and Health Management Costs-appropriated under the rate of indirect costs-to be appropriated as direct construction costs. As a preliminary step in this effort, the current study will provide basic data that can be used to create construction cost calculation standards for items that can be calculated as direct construction costs.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.145-150
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• 2013

As a recent global trend, the majority of mega-size plant projects are delivered through EPC (Engineering, Procurement and Construction) contracts, where a single contract is awarded for engineering, procurement, and construction. Under this contracting mechanism, it is challenging for contractors to carry out the projects under traditional project management processes used in design-bid-build projects. A new EPC Plant, the POSCO Special Steel Plant in Changwon, was built successfully at the beginning of 2012 and it is currently in full-scale production. The project has encountered a number of major difficulties however, with some technical and managerial issues through its development process. As summarized in this paper, the authors (as project participants with the contractor) investigated it as a post construction analysis and recorded the Lessons-learned for future project management improvement.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.973-981
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• 2008

This document presents the JES(Joint Element Structure) method that has been adopted for the firs time in our country for the construction of the structure crossing under the railroad without open excavation. Front Jacking Method, Tubular Roof Construction Method, New Tubular Roof Method and Joint Element Structure Method are commonly used for the construction of structures crossing under the railroad. JES Method, frequently used in Japan recently, is a new method to construct the structures crossing under the railroad in a safe manner and in a relatively short period of time by utilizing the steel elements with the joints through which the load in the vertical angle to the axial direction is transferred to the next element. The elements are tied to each other through the joints to form the permanent walls of a Rahmen structure under the road without open excavation and without limitation to the length in a convenient way. Through the case study in the project of a Subway Box Culvert Improvement for the Gyeonguiseon Railroad in front of Yonsei University using the JES Method, the cost and period of construction in various types of soil is investigated compared to the Front Jacking Method. Furthermore, by analyzing the results of instrumentation measurements carried out throughout the construction, comparison between the actual displacement in the ground and the predicted displacement in the design is made to provide the considerations to be counted for the design. In conclusion, comparison in the field of economic feasibility, constructability and safety between the JES Method and Front Jacking Method, which is most frequently adopted in our country at present, is made to present the JES Method as a new alternative for the non-open excavation construction method for the structures crossing under the railway.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.117-120
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• 2008

Recently, according to the increasement of high-rise building construction and domestic situation, requirements of rapid cycle construction are increasing. For more economical and rapid cycle construction, it is required to reduce formwork cost. So formwork have to be stripped as soon as possible. But as fresh concrete is loaded with construction load, it is likely that the structure will have problems with safety and serviceability. To reduce construction cycle economically, safety and serviceability of structure against construction load have to be considered. But as behavior of structure under construction is so complicated, behavior of structure has to be investigated according to construction stage. Therefore, through field instrumentation of apartment, behavior of structure under construction was analyzed.

• Journal of the Korean Society of Safety
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• v.31 no.4
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• pp.104-110
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• 2016

The effect of a partially earth anchored cable system on the structural safety of a long span cable-stayed bridge under seismic and wind loads are examined during construction process. By assuming the FCM (free cantilever method) construction stages with structural vulnerability, a multi-mode spectral analysis and a multi-mode buffeting analysis are performed for specific seismic load and wind load, respectively. Results show that the wind load dominates the structural safety of a cable-stayed bridge during construction. And, the application of a partially earth anchored cable system can enhance structural safety under wind load since the maximum pylon moment in the model with partially earth anchored cable system is reduced by 49% under wind load. In contrast, the maximum pylon moment occurred by seismic load is only decreased by 8%.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1036-1041
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• 2008

In order to analysis the reason of sliding failure in embankment slope under construction in soft soil area, a model section located in Gimhae Region in Gyeongsangnam-Do, where the sliding failure had been occurred during embankment works in soft soil area, had been selected. This area had been firstly treated with the Pack Drain Method, and additional embankment works of 9.7 meters out of total 14 meters in thickness had been under construction. The results of analysis showed that the reason of sliding failure were overspeed in embankment construction and the overestimation of design factors in calculating strength of each layer of embankment and poor management and inaccuracy reading of measurement devices.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.201-208
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• 2011

Today's highly competitive construction scenario forces all the major players in the field to take up multiple projects which have put an undue pressure on the resources available within the organization. Under such a situation, there are many instances where in the resource requirement exceeds its availability due to multiple activities (with same resource requirement) which are scheduled to start simultaneously and thus results in the constrained resource becoming a bottleneck of the project. As a consequence of sharing resources, this paper studies the impact on the completion date of two similar projects under two different conditions, the first one resulting in a postponed end date and the second without any postponement. The resource utilization, the possibility of substitution of a resource and its subsequent impact on the deadline of the project is analyzed under these two circumstances. The study is done on a Critical Chain Project Management (CCPM) platform instead of leaving the schedule with a traditional Critical Path Method (CPM) finish, which gives an added advantage of validating the robustness of the emerging CCPM trend in the field of resource management.

• Journal of Construction Engineering and Project Management
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• v.7 no.4
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• pp.1-12
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• 2017

India has accorded a high priority to road infrastructure development through Public-Private Partnership (PPP) and it has set a high target for investment inflows. Yet, it is widely held that road/highway infrastructure has not been developing at required pace and that the road infrastructure projects under PPP have been suffering from several hurdles and delays, thereby affecting project success/failure. This paper is an attempt to analyze the critical success/failure factors of road infrastructure projects under PPP in India. A questionnaire survey was conducted among a sample of the stakeholders of road infrastructure projects to identify the critical success/failure factors during all four major project stages using different approaches. Initially, the critical factors were identified through ranking based on the average/mean score. Later, the conventional RII score was used to identify the critical success/failure factors. Finally, the critical success/failure factors were also identified based on the stakeholder-wise ranking of the factors and their convergence. The assessment revealed that there was a greater convergence across the different methods and also that there was greater consensus among project stakeholder on the critical success/failure factors of road PPP projects.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.115-118
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• 2010

The concept of construction information systems (IS) is very comprehensive and subjective. Acronyms in relation to the construction IS may include BIM, CIC, IT, nD-CAD, ERP, CALS, KM and so on. These terminologies are used in a somewhat mixed way causing possible misunderstandings in research and practice of construction information systems. Moreover, ever-changing construction business environment has widely affected the roles and methods of utilizing construction IS. Examples of these changes are dissemination of alternative project delivery systems, global standardization under highly competitive overseas market, and advancement of information and communication technologies. In this context, the purpose of this paper is to propose a high-level framework for information systems in the construction industry. Several different concepts in the area of construction IS were investigated first in order to identify the major variables of the framework. Trends of research and real-world implementations were then analyzed to support the rationale of the variables. Finally, a framework was proposed by re-arranging the relevant issues. Findings of this paper indicate that different acronyms commonly share many similar concepts in their definitions, however, in each acronym, the motivations and approaches to implementing construction IS are very different. Different approach can provide maximum effectiveness, while overlaps may happen causing practical inefficiency.