• Journal of the Korea Institute of Building Construction
• /
• v.12 no.5
• /
• pp.518-527
• /
• 2012

This study uses a hybrid estimation tool for effective cost data management of building projects, and develops a realistic cost estimation model. The method makes use of newly available information as the project progresses, and project cost and percentage progress are analyzed and used as inputs for the developed system. For model development, case-based reasoning (CBR) is proposed, as it enables complex nonlinear mapping. This study also investigates analytic hierarchy process (AHP) for weight generation and applies them to a real project case. Real case studies are used to demonstrate and validate the benefits of the proposed approach. By using this method, an evaluation of actual project performance can be developed that appropriately considers the natural variability of construction costs.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.22 no.4
• /
• pp.329-336
• /
• 2012

Objectives: The aim of this study is to analyze main problems on occupational safety and hygiene in construction sites and to suggest some improvement methods. In order to decrease industrial accidents, I emphasize the approach paradigm shifts according to characteristics of construction workers. Methods: Pointing out the irrationality of current institutions by comparing bad outcomes of occupational safety and hygiene in construction industry and characteristics of construction workers. Results: In order to decrease industrial accidents, we need some approach paradigm shifts; the supply method of industrial safety and health fundamentals on the construction industry level, the accident rate calculation by using the actual construction workforce instead of an estimation, institutionalizing the prevention efforts themselves for industrial accidents, securing enough production costs for the precondition of occupational safety and hygiene in construction sites. Conclusions: I ascertain the need of the approach paradigm shifts for decreasing industrial accidents in the construction industry.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.33 no.4
• /
• pp.10-22
• /
• 2010

The first full-scale u-City operation has started in Dongtan u-City. As local cities take over and operate the u-City, unexpected issues arise such as securing the budget of operating costs and self-providing the costs with business models utilizing the u-City assets. The paper presents a strategy for solving these issues. The strategy provides a foundation(infrastructure) for long-term operation models which may reduce the long-term operating costs. In order to establish the economic operating framework of u-City, suggested are some cost-reduction models based on the operating costs structure. For each model, a base framework with comparative analysis of operating costs is provided. With these models, each u-City may select a relevant model according to the characteristics of it. We hope that the framework provides the foundation for efficient and sustainable u-City operations.

• Journal of the Korean Society of Safety
• /
• v.22 no.5
• /
• pp.33-40
• /
• 2007

Standard safety management costs can not be applied to each site with same rate, it is very difficult, because it depends on the experience, work method, work kind, work progress schedule, and hazard level of each construction company. Therefore, this study is to find out hazard level of each work kinds through questionnaire and interview and investigate analyze the status which standard safety management costs have been used. Also, this study is to show reasonable rates of standard safety management costs in construction industry and to set up countermeasures against those problem after reviewing its status in korea with in Japan and Europe. This study is to investigate eleven project kinds of domestic system, first, and to investigate eleven items of apartment bldg, office. Also this study is to investigate and analyze performed costs of presently processing worker finished work so that it shows a new reasonable rate against standard safety management costs in construction industry, in order to make basical data and material to be systemized.

• Journal of the Korea Safety Management & Science
• /
• v.16 no.3
• /
• pp.23-34
• /
• 2014

With a view to analyzing the influential factors and their prioritization in association with the loss from construction disasters, this study has presented relative weighted value and importance for each category of loss by making a systematic classification of costs for non-insured categories (indirect costs) and conducting AHP analysis based on results of a survey of specialists. Through the study, first, I have divided the larger classification of loss factors into human loss factor, financial loss factor, special cost factor, and managerial loss factor, and, second, have presented prioritization of loss categories by allotting scores based on weighted values after calculating weighted value through pairwise comparison of loss levels. Based on these results of the study, we should be able to qualitatively calculate the loss costs that construction disasters inflict on business, promote rational decision-making and efficiency in spending related to a disaster, and compare it against safety investment designed to reduce disaster loss from the perspective of business strategy.

• Structural Engineering and Mechanics
• /
• v.43 no.1
• /
• pp.31-51
• /
• 2012

This paper presents a computational study that explores the design of rigid steel frames by considering construction related costs. More specifically, two different aspects are investigated in this study focusing on the effects of (a) reducing the number of labor intensive rigid connections within a frame of given geometric layout, and (b) reducing the number of different member section types used in the frame. A genetic algorithm based optimization framework searches design space for these objectives. Unlike some studies that express connection cost as a factor of the entire frame weight, here connections and their associated cost factors are explicitly represented at the member level to evaluate the cost of connections associated with each beam. In addition, because variety in member section types can drive up construction related costs, its effects are evaluated implicitly by generating curves that show the trade off between cost and different numbers of section types used within the frame. Our results show that designs in which all connections are considered to be rigid can be excessively conservative: rigid connections can often be eliminated without any appreciable increase in frame weight, resulting in a reduction in overall cost. Eliminating additional rigid connections leads to further reductions in cost, even as frame weight increases, up to a certain point. These complex relationships between overall cost, rigid connections, and member section types are presented for a representative five-story steel frame.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.17 no.4
• /
• pp.101-111
• /
• 2013

In this study, DEA (Data Envelopment Analysis) was carried out on the four bridges, which have the same extension (L=1,615m), in order to select the most superior, economical method of construction using the LCC concept of each bridge structure in the case of the Ulsan-Pohang double track railway which is scheduled to be constructed. DEA models were analyzed with the CCR model, which was designed for the evaluation of relative efficiency of each model. The initial construction costs, maintenance costs, indirect costs (user costs + indirect loss of social costs), and life cycle costs were used as input variables, and average duration was applied as the output variable. LCC was applied to calculate the input variables, and to get the costs of LCC, 100 years of period and 4.83% of real discount rate were applied, and the costs are classified into initial construction, maintenance, user, and indirect loss of social cost. The analysis results showed that the Method 2 and 3 were evaluated as the most efficient, and the other alternatives were evaluated as the following order; Method 1, the default, and Method 4.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2022.04a
• /
• pp.198-199
• /
• 2022

Reinforced concrete is the most widely used construction method for constructing structures. There is a lot of process for constructing Reinforced concrete structures such as installing rebars, molds and support, mixing and placing concrete, and curing. So the reinforced concrete work accounts for a large part of the total construction cost for constructing structure. For this reason a reasonable standard for estimating the cost of reinforced concrete construction has to be established and it will be possible to secure appropriate costs for construction work. In this study, we analyze the revision factors of the standard for estimating the cost of reinforced concrete construction and present them to secure reasonable construction costs.

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

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2008.11a
• /
• pp.409-414
• /
• 2008

The purpose of this study is to analyze the problem of BTL business through the sensitivity analysis of financial model and presented efficiency business strategy when private business owner propose their business. For this, we analyzed the sensitivity of financial model after analyzed costs of the school facility construction case for each place of business. The results of this study are as follows. 1)As the results of the sensitivity of financial model, requirement-earning rate for the results of analysis was decreased average 2.28 points (0.5%) per increasing 0.10% and Construction costs and the maintenance costs were decreased average 10.73 points (2.38%), 6.22 points(1.38%) for increasing 1billion won. 2) The Problem of BTL business according to the sensitivity analysis of financial model was analyzed that the price consultation low investments, and estimation from personal consideration caused it. So, it was analyzed to increase maintenance costs is more efficient method than to increase construction costs.