• Proceedings of the KSR Conference
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• 2008.11b
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• pp.905-917
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• 2008

Road or Railway construction over soft ground is needed to be considered on secondary consolidation which will be caused differential settlement, lack of transport serviceability, higher maintenance cost. Especially for the railway construction in the second phase of Gyung-Bu or Ho-Nam high speed railway, concrete slab track has been adapted as a safe and cost effective geotechnical solution. In this case controlling the total settlement under the tolerance is essential. And pile supported geogrid reinforced construction method is suggested as a solution for the problem of the traditional method on soft soil treatments. Pile supported geogrid reinforced construction method consists of piles that are designed to transfer the load of the embankment through the compressible soil layer to a firm foundation. The load from the embankment must be effectively transferred to the piles to prevent punching of the piles through the embankment fill creating differential settlement at the surface of the embankment. The arrangement of the piles can create soil arching to carry the load of embankment to the piles. In order to minimize the number of piles geogrid reinforced pile supported construction method is being used on a regular basis. This method consists of one or more layers of geogrid reinforcement placed between the top of the piles and the bottom of the embankment. This paper presents several methods of pile supported geogrid reinforced construction and calculation results from the several methods and comparison of them.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.289-290
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• 2023

According to relevant laws, in the case of a construction project with a total construction cost of 30 billion won or more, a post-construction evaluation must be performed after completion. In addition, a post-construction evaluation report must be prepared and entered into the Continuous Acquisition & Life-cycle Support(CALS). As a result of reviewing the currently accumulated post-construction evaluation reports, since the report is not standardized, it is difficult for public project owners to write the report. It also hinders the post-construction evaluation and management center from verifying contents, analyzing data, and deriving meaningful results. In order to improve the convenience of the public owners who must conduct post-construction evaluations and the work efficiency of the center, evaluation factors were standardized and a standard post-construction evaluation report format for road construction was developed in Excel. Through this, the data in the reports will be effectively accumulated, managed, and analyzed, so that meaningful results will be produced and be helpful in future construction work.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.802-807
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• 2005

For linear projects, it has long been known that resource utilization is important in improving work efficiency. However, most existing scheduling techniques cannot satisfy the need for solving such issues. This paper presents an optimization model for solving linear scheduling problems involving resource assignment tasks. The proposed model adopts constraint programming (CP) as the searching algorithm for model formulation, and the proposed model is designed to optimize project total cost. Additionally, the concept of outsourcing resources is introduced here to improve project performance.

• Korean Journal of Construction Engineering and Management
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• v.15 no.1
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• pp.101-110
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• 2014

The ministry of Land, Infrastructure and Transport announced that they launched the pilot project to offer Happy House built with modular construction as part of the major projects of incumbent government in 2013. The market size of modular construction is getting increasingly enlarged together with strong will of government. The major challenges that current modular construction encounters can be summed up as lack of standardization of material on the stage of design and fabrication. The portion of material costs in modular construction marks 16 to 17% higher than the existing other construction method, and account for 60 % of total construction cost, which is why material management is the most important factor. However, the imperfect standardization and specification on design causes high loss of materials on fabrication, which makes the construction wastes and total construction cost increasing in accordance with the increase of material costs. This study has been conducted to verify major modules by developing optimization algorithm on gypsum board material among wall finishing materials. It is expected that this paper contributes not only to eco-friendly construction by minimizing the waste factors of materials through these efforts, but also to removing high cost issues which had been recognized as a setback of current modular construction.

• Korean Journal of Construction Engineering and Management
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• v.21 no.1
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• pp.32-39
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• 2020

The purpose of this study is to derive the risk factors that occurred during the construction of the temporary aircraft runway and to analyse the risk costs and loss costs. For this purpose, actual construction data made during the construction of the aircraft runway were investigated. And the risk factors that occurred during the construction work were derived. So the increased construction costs and loss costs due to risk factors were analyzed. The results of this study are as follows: 1)The number of risk factors that occurred during the construction of the aircraft runway was derived from eight. 2)It was calculated that the total risk cost of 5.2million won, the risk cost of the owner's should be 243 million won and the cost of the contractor should be 277million won. 3)Owner's was up 2.36% from its planned budget and the contractor lost -277million won out of its planned profit of 443million won, resulting in a residual profit of 165million won. The results of the study are used as a reference for estimating risk factors and contingency that should be considered in aircraft runway construction.

• Journal of the Korea Institute of Building Construction
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• v.9 no.6
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• pp.161-168
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• 2009

In an architectural construction, underground construction is a critical path forming a major part of the total construction period and cost, and particularly in big cities, its size has been increasing every year. A basement wall currently constructed in the field needs a large functional work force, and the construction is under progress by the Euroform and Soldier system, which is disadvantageous in terms of the construction period. Therefore, in this research, non-supporting forms which are applicable to the buildings construction were developed, based on the non-supporting forms partly used in some civil engineering works. In addition, the size of a form was assumed and its economical efficiency was compared to that of the Euroform and Soldier system which is used most in construction fields, and the results were analyzed. The study results showed that the construction cost of composite non-supporting forms was higher than that of the Euroform and Soldier system by about 8%, and the construction cost of non-composite non-supporting forms were lower than that of the Euroform and Soldier system by about 9%. However, in the case of composite non-supporting forms, the amount of concrete and reinforcing rods remarkably decreased in structural construction, so it has the effect of an economical cost reduction compared to the construction cost of existing walls by about 35%

• Journal of the Korea Institute of Building Construction
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• v.12 no.3
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• pp.257-265
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• 2012

Many construction companies are simultaneously carrying out numerous projects in the housing construction industry. It is essential to accurately forecast the cash flow of a project through optimal process management and resource input in order to manage funds rationally and enhance the competitiveness of a company. Current cash flow forecasting methods offer lower accuracy due to a large gap between the revenue and expenditure element. Expenditure elements depends on the real-time changing actual cost for work performed. This research survey was conducted on the actual state of construction management of K company to investigate the problems of cash flow forecasting. To achieve this, the work process and construction management system were integrated to improve the cost management system of K company. To accurately forecast the cash flow of a project, revenue and expenditure elements were displayed in the total cash flow forecast window. This research is expected to assist in the implementation of a system of cash flow forecasting on housing construction by excluding negative elements of revenue and expenditure.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.209-210
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• 2012

In this study, the following conclusions are drawn. First, the Inorganic terazzo tile flooring and LCC (Life Cycle Cost) analysis showed that the sum of the total cost of 150,304 won Inorganic flooring, terrazzo tile flooring minerals won 186,202 to 35,898 won, compared to 8.22% analysis of the cost savings that have been appearing. Second, if the color chip has a unique and elegant sentence patterns, beautiful and high-strength bonding and that the crack resistance was investigated.

• International Journal of Railway
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• v.5 no.3
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• pp.103-113
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• 2012

Infrastructure costs could be greatly reduced if the need for bridges and tunnels was reduced, or if the line could be shortened. Tilting trains might be a less costly alternative to building new tracks with large curve radii, because tilting trains can negotiate tighter curves without having to decrease their speeds. Tracks built for tilting trains would be cheaper, as they require fewer bridges and tunnels. This paper compares the construction costs of two different options for the new Dodam-Yeoncheong section on the Central line, which includes 148.65 km of new electrified double-track with a design speed of 250 km/h. The first option is to straighten the high-speed line. The second option is to build a line with small radii curves and run tilting trains on the line. In the first option, tunnels would account for about 51% of the new section. In comparison, the second option would have shorter curves and fewer tunnels and bridges which would reduce construction costs. Furthermore, alignment modifications could be made to several segments on the straight line, making the most of the existing roadbed. The analysis concluded that the line suited to tilting trains would be 95.7 million USD cheaper to build the straight route. That is a savings of 2.8% of the total project cost. However, this option would increase the total travel time of the route by 1.2 minutes, which means it is not necessarily the best choice.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.6
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• pp.625-631
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• 2008

Correct evaluation of cut and fill volume of soil is one of the most important factors which controls construction cost in enormous construction sites. To achieve accurate computation of soil volume in construction site precise surveying is required, however most of construction sites adopt existing optical surveying instruments such as Total Station. The problem when using these optical instruments in construction sites is that these instruments take longer time in data acquisition. Due to insufficiency of computation time accurate and precise observation cannot be accomplished with these equipments. As a result roughly calculated earthwork volume may cause arguments between contractors and supervisors in the matter of reduction or increasement of total construction cost. In this study VRS-RTK Surveying is adopted to perform fast and accurate in-situ surveying for rapid computation of soil volume. This VRS-RTK Surveying system is proved to have more accurate three dimensional coordinates with high density and better economical solution with less manpower.