• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2575-2582
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• 2013

In the delivery systems for public construction works, design-build methods such as turn-key and alternative have contributed to improving the quality of structures and developing the construction technology. However, it is pointed out that construction based on a design-build method is likely to waste a budget due to its higher contract price than construction based on a design-bid-build method. Other issues such as contract monopoly, bid rigging and deliberation irregularity in design-build. Since there are not much works have been accomplished to comparatively analyze the actual performance and effect based on delivery methods, discussing and judging the performance and effect of each deliver method with limited information could lead to an error. Thus, this study by extensively investigates the actual project cost data, ranging from contract price to the construction cost of the public construction works and comparatively analyzed the characteristics of each delivery method about cost structure and fluctuation trend. This work is expected to assist stake-holders in properly understanding delivery systems for public construction works and promoting their efficient management.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.103-104
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• 2016

Most of studies on PC method aim at the structural analysis and development of PC members, and studies on the construction management aspect are insufficient. This study is a basic research in the construction management aspect regarding 'composite method using hollow-PC column' (HPC method), and is intended to develop assessment standards for the benefit·cost analysis of HPC method. Assessment standards for the benefit·cost analysis were composed of main-factors and sub-factors through interview with 4 experts. It was possible to classify main-factors into 4 major categories, i.e,. structural performance, construction performance, construction duration and construction cost. Sub-factors were composed of factors which were of high importance in assessing the two methods. And factors judged to be repeated or of little importance were excluded.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.1187-1192
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• 2005

Approximately 25% of military establishments became superannuated to unable perform their function, and it influences on the environment by construction wastes and the waste of national budget, as there is no rational and objective standard even though old facilities have been replaced through modernization project. Therefore, it has been searched to introduce industrial building system that can cope with the new building-construction and transference for the improvement of existing military establishments. However, as there is no economical estimation standard for practical use, industrial building-construction is still remaining at the initial stage, and the study is insufficient too. So. in this study, I would like to develope LCC cost model for rational LCC comparative analysis between industrial construction system (Modular) and existing reinforced concrete structure and cage, and to evaluate economical efficiency through case analysis.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.2
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• pp.409-417
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• 2017

The study is concerned with doing research on the plan to prevent the dispute occurring between contract parties regarding the additional cost generated when the construction period is shortened during construction work. After the review of the claim cases and the judgment cases of the court regarding the additional cost caused by the shortened construction period, the representative problem is the incomplete regulations on calculating the additional cost. In the 1st stage of the results of the research on the problem, the procedure handling the additional cost is presented, and the process of planning and approving the shortening of the construction period is gone through in the stage of the procedure to prevent the dispute on the additional cost between contract parties. In the 2nd stage, the plan on enacting and revising the regulations on removing the incomplete problems of the current regulations relating to the calculation of the additional cost. The basis for the advanced contract management is provided by resolving the incomplete problems of the current regulations relating to the shortening of the construction period with the prevention of a dispute and the resultant loss.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.475-478
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• 2013

To carry out a one-off construction project successfully, effective and accurate early cost estimation is crucial, especially during the conceptual stage where very limited minimum information of construction project is given. As the level of accuracy of the early cost estimation has huge impacts on precise budgeting and cost management of a project, in other words, reducing the risk of a project, cost must be managed with special awareness. In an effort to improve the estimate accuracy of cost during the conceptual stage, this research introduces a Parameter Impact (PI) which can quantify weights of parameters and rank them; and PI development derived from the principle of impulse in physics is explicated. For a case study, 76 public apartment building cases in Korea are analyzed. To examine the validity of the proposed PI, a validation in terms of CBR applicability test and estimate accuracy comparisons using 10-nearest neighbor cases are carried out. The validation results support that the suggested PI can be applied in quantifying the weights of the parameters and CBR method for early cost estimation.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.273-279
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• 2011

Concerns over the environment have spawned a number of research studies in the construction industry, as the construction of built environments and large infrastructures involves diverse environmental impacts and loads of hazardous emissions. Many researchers have attempted to quantify these environmental loads, including greenhouse gases, carbon dioxide, nitrogen dioxide, and sulfur dioxide, to name a few. However, little research has been conducted regarding integrating the life-cycle assessment (LCA) of environmental loads with the current life-cycle cost analysis (LCCA) approach. This study aims to estimate the environmental loads as a monetary value using the European Climate Exchange (ECX) rate and, then, to integrate those impacts with the pure construction cost. Toward this end, this study suggests an integrated approach that takes into account the environmental effect on the evaluation of the life-cycle cost (LCC). The bill of quantity (BOQ) data of a real highway project are collected and analyzed for this purpose. As a result, considering the environmental loads in the pavement process, the total LCC increased 16% from the traditional LCC cost. This study suggests an integrated approach that will account the environmental effect on the LCC. Additionally, this study is expected to contribute to better decision-making, from the perspective of more sustainable development, for government as well as for contractors.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.493-498
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• 2009

Recently, the number of complex construction projects, such as high-density development and long-span mega structure construction, has been increasing globally. Therefore, the construction duration has become an even more important factor for success. Nevertheless, in domestic residential construction projects, it usually takes more time than twice as much as North American cases. The long construction duration causes a number of problems, for example growth of financial costs, fall in productivity, and weakness of competitiveness. If the framework construction duration can be shortened to 3 ~ 4 days, then it is also expected to complete the finish work of building in shorter duration, be led to reduce the entire construction duration, and eventually to save a great deal of indirect costs. For shortening the construction duration, previous researches pointed out that the development of simplified plan design should precedes. But, in reality, lack of experience of new design and innovative techniques tends to be the obstacle to wide adoption of the simplified plan design in construction fields. In this paper, a simplified structural plan design is proposed, and the construction cost is quantitatively compared between when traditional construction technique is applied to the traditional plan and when the duration-shortening key technique is applied to the developed plan.

• Korean Journal of Construction Engineering and Management
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• v.7 no.6
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• pp.193-201
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• 2006

The Evaluation system of Excellent Construction Technology has been operated for 15 years from 1990 in Korea. 443 technologies have been certified as Excellent Construction Technology(ECT) and those ECTs are adapted over 20,000 times into the construction projects. As a result of investigation, new technology evaluation system became a stable stage because new technology evaluation system has assigned about 433 and also applied more than 20,000 times in construction sites in 2004. However, it was indicated to a large problem that there aren't still detail criteria of cost assessment for using ECTs. Therefore, we analyzed the status and problems of the cost of using ECTs and suggested some useful ideas which are reviewed by various aspects. Specially we suggested specified criteria for the cost assessment of using ECTs. It is based on the scheduled construction cost and determined the rate $({\bullet}{\cdot})$ of using ECTs. To adapt ECTs into construction projects nationwide not only it is very important to certify better new technologies but also it is required to make the criteria of cost assessment for using ECTs.

• Korean Journal of Construction Engineering and Management
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• v.7 no.5
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• pp.159-166
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• 2006

It was found that Korean Standard of Estimate which has been used as the only basis of cost estimate of public construction projects had some side effects such as jerry-build construction and over-estimation because it failed to reflect the current price and the state-of-the-art construction methods in a changing construction environment. Therefore, the government decided to gradually introduce historical construction cost into cost estimate of public construction projects from 2004. This paper presents analytic criteria and a process model for deducing more current and reasonable historical construction cost for contract items from not only previous contract prices but also all of the other bid prices that were not contracted. The procedure of estimating actual unit cost proposed in this paper focuses on the removal of abnormal values including strategically too low or high prices and the time correction. In addition, basic research is conducted for the correction of actual unit cost through the analysis of fluctuation of bid price depending on bidding types and rates of successful bid. It is anticipated that the effective use of the proposed process model for estimating actual unit cost would make the cost estimation more current and reasonable.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.823-830
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• 2022

The risk of project execution increases due to the enlargement and complexity of Engineering, Procurement, and Construction (EPC) plant projects. In the fourth industrial revolution era, there is an increasing need to utilize a large amount of data generated during project execution. The design is a key element for the success of the EPC plant project. Although the design cost is about 5% of the total EPC project cost, it is a critical process that affects the entire subsequent process, such as construction, installation, and operation & maintenance (O&M). This study aims to develop a system using machine-learning (ML) techniques to predict risks and support decision-making based on big data generated in an EPC project's design and construction stages. As a result, three main modules were developed: (M1) the design cost estimation module, (M2) the design error check module, and (M3) the change order forecasting module. M1 estimated design cost based on project data such as contract amount, construction period, total design cost, and man-hour (M/H). M2 and M3 are applications for predicting the severity of schedule delay and cost over-run due to design errors and change orders through unstructured text data extracted from engineering documents. A validation test was performed through a case study to verify the model applied to each module. It is expected to improve the risk response capability of EPC contractors in the design and construction stage through this study.