• 보일러설비
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• s.42
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• pp.102-105
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• 1997

• Korean Journal of Construction Engineering and Management
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• v.9 no.6
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• pp.175-184
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• 2008

For deciding the profitability and feasibility of the construction project, the schematic estimation has to not only link the design decision-making but also estimate the cost with reliability. The prototype-based schematic estimation system was developed for easily linking with design-making and supports to evaluate the design alternatives in the design development stage but didn't consider the cost estimated by parameter and additional work items by users. This research presents the object-parameter based schematic estimation model in the design development stage that can lead to accurately estimate the cost by using historical data from the high-storied office buildings. For the development of the proposed model for schematic estimation, after analyzing and classifying the work items from the Bills of Quantities(BOQs) and drawings of historical data, this research proposed the methods of estimating cost in accordance with attributes of each work item. In addition, a case study is performed for the effectiveness as comparing the previous estimating method with the proposed model.

• 월간 기계설비
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• s.242
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• pp.19-21
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• 2010

공정거래위원회가 하도급계약 추정제에 따른 통지나 회신 방법 규정, 기술재료의 정의 등을 골자로 하는 '하도급거래공정화에관한법률시행령' 개정안을 마련하고 지난 7월 26일부터 시행에 들어갔다. 하도급계약 추정제는 하도급거래에서 수급사업자를 보호하기 위해 수급사업자가 구두로 맺은 계약에 대해 확인을 요청할 때 원사업자가 15일 이내에 이를 부인하지 않으면 계약이 있었던 것으로 추정하는 제도이다. 공정위는 또 수급사업자가 원사업자에게 위탁을 받은 작업의 내용과 하도급대금, 위탁받은 일시, 원사업자와 수급사업자의 사업자명과 주소 그밖의 원사업자에게 위탁한 내용 등으로 정했다. 개정된 하도급법에는 원사업자가 수급사업자에게 기술자료를 제공하도록 강요하지 못하도록 기술자료의 범위도 정했다. 또한 상습적으로 법을 위반하는 사업자의 명단을 공개하는 기준도 마련됐다. 명단 공개 기준은 최근 3년간 벌점이 4점을 초과한 자로서, 사업자명과 대표자, 사업장 주소 공개와 함께 공정위 인터넷 홈페이지에 이를 게시할 때는 그 기간을 1년으로 했다. 이와 함께 입찰명세서와 낙찰자결정 품의서, 견적서, 현장설명서, 설계설명서 등 하도급대금결정 관련서류를 의무적으로 보존토록 하고 하도급대금 지급보증기관에 소방산업공제조합을 추가해 원사업자의 지급보증기관 선택 범위를 확대했다.

• 월간 기계설비
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• no.8 s.217
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• pp.64-67
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• 2008

해외공사는 주로 해외지점망, 외국설계회사, 발주자 또는 기존 현장을 통해 입수한 공사정보(공사비 및 공사개요, 재원, 발주자, 설계회사, 입찰일정 등)를 토대로 입찰참여 여부를 결정하며, 입찰 자격심사(PQ : Pre-qualification)를 거쳐, 입찰서를 발급받아 견적서를 작성하고 입찰에 임하게 된다. 입찰, 수주활동을 하는 동안 주요사항을 국토해양부 및 해외건설협회에 단계별로 소정의 양식에 의거 보고한다. 주요보고사항 $\Delta$ 수주활동상황보고(입찰예정일 10일 전까지) $\Delta$ 계약체결결과보고(계약체결 15일 이내) $\Delta$ 시공상황보고(매분기 종료후 30일 이내) $\Delta$ 공사내용변경보고(변경 15일 이내) $\Delta$ 준공보고(준공증명서 발급 15일 이내)

• Korean Journal of Construction Engineering and Management
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• v.20 no.6
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• pp.89-97
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• 2019

Recently, BIM has been actively introduced in construction projects. In particular, the introduction of BIM in cost estimating process is expected to improve the accuracy and efficiency of the cost estimate. However, the quantity calculation and BoQ documents preparation process still require manual work. Although the BIM model may support quantification process, it is still problematic that the level of detail of the model must be very detailed to meet the items in BoQ. To address this, it is necessary to analyse the LOD criteria and to analyze the extent to which quantity can be computed according to the level of detail in the BIM model. For the analysis of LOD-based work items, the work item grades were divided into A,B, and C. In this study, the ratio and cost of each item that can be calculated at the LOD level in the detailed design phase are reviewed for each type of work, and the method for improving the quantity calculation using BIM is proposed. In the LOD 300 stage(Detailed design stage), the largest number of items in the class B, the major improvement class, are window and glass work. In addition, the most expensive type of work was analyzed by reinforced concrete work. In the future, it is necessary to suggest appropriate improvement way for items with high item ratios and items with high cost ratios. The results of this study are expected to be used as a BIM-based cost estimation or as basic data for improving the current BoQ system.

• Journal of the Korea Institute of Building Construction
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• v.20 no.2
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• pp.147-153
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• 2020

It is important to estimate the optimal construction cost at the early stage of the project. In this regard, conceptual cost estimate is an important factor for estimate optimal construction cost. However, domestic conceptual cost estimate are only used as cost per unit area according to the building type, and it's accuracy is not high. Hence, the purpose of this study is to calculate the approximate quantity and cost for reinforcing bars, concrete, and formwork by presenting a regression formula based on the total floor area of the common work items in the frame work. In order to verify the accuracy and validity of the regression formula presented in this study, a comparative analysis was performed by applying the regression formula and the traditional approximate quantity take-off method to real cases. As a result, the estimated error rate of the traditional method was -102~+55%, and exceeded the estimated conceptual cost estimate accuracy range of -50~+100% suggested by AACE(American Association of Cost Engineering). On the other hand, the error rate of the regression formula method presented in this study was -6.4~+11.62%. This can be used not only for conceptual cost estimate range of accuracy, but also for detailed estimates. However, it is necessary to analyze the factors that affect the unit price as well as quantity in order to calculate the appropriate cost.

• Korean Journal of Construction Engineering and Management
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• v.17 no.1
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• pp.56-65
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• 2016

Many cases have mentioned the effect by applying BIM on the media such as at conferences, workshops, reports, ect. These cases reported that costs could be saved directly by prevention the need to re-do and reconstruct caused by using BIM. BIM users mentioned that using BIM has potential value in saving costs. The benefits of the BIM include intangible value that cannot be estimated in costs, such as reducing work time and improving productivity. However, the financial value of using BIM, such as Return on Investment, has not yet been exposed, and BIM users have a negative view of the financial value of BIM in Korea. Therefore, this study has researched the effects of applying BIM on construction estimate services in view of business productivity, not finance. This study compared the traditional and BIM based estimation, and verified the effect of estimating BIM through work sampling. This study investigated a precondition for getting the effects of BIM based estimation. The results show a need for BIM education, 3D Modeling standards, and database on quantity in order to improve product ivity and reduce work time on BIM based estimation

• Korean Journal of Construction Engineering and Management
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• v.12 no.5
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• pp.23-34
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• 2011

Reliable progress management at construction requires integrated information of cost and schedule, and information is used as a basis for project performance measurement. However, separate handling of cost and schedule information at construction projects makes objective measurement more difficult and decreases management productivity due to additional works for breaking down bill of quantities into corresponding activities. Recently, research related to BIM addresses issues on effective progress management based on BIM with incorporation of daily progress management. Therefore, the objective of this paper is to propose information model for daily progress rate and budgeted cost of work performed by utilizing BTM-based quantity and location information.

• Journal of the Korea Institute of Building Construction
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• v.19 no.6
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• pp.521-527
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• 2019

Quantity takeoff and cost estimates in Korea are carried out in practice without any clear standards or standards. Especially, quantity takeoff of Reinforcing bar and BoQ documentation process is very complex using 2D drawings. In this study, 10 case sites were analyzed for the status of inefficient quantity takeoff and how the statement was prepared. In order to solve this problem, this study presented a method for calculating the quantity of rebars through the ratio of concrete volume for schools, offices, and apartment buildings, and analyzed the accuracy of results. In the future, it is expected that the error range can be reduced by defining the factors affecting the results and calculating the correction value for them.

• Korean Journal of Construction Engineering and Management
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• v.1 no.1 s.1
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• pp.63-71
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• 2000

The paper considers two non-deterministic methods of analysing the risk exposure in a cost estimate The fist method(referred to as the 'conventional statistical' method) analyses cost data directly, to describe a probability distribution for total cost. The second method(referred to as the 'Monte Carlo simulation' method) interprets cost data directly, to generate a probability distribution for total costs from the descriptions of elemental cost distribution. The common practice of allowing for risk through an all-embracing contingency sum or percentage addition is challenged. Rather than excluding conventional, non-deterministic methods, they are here presented as possibly the only of effective foundation on which to risk management in cost estimating.