• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.1
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• pp.35-44
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• 2020

In the construction industry, there is a growing demand for the accurate calculation of the quantity take-off and construction budget at the design stage, and it is likewise important to grasp changes in the construction budget and quantity take-off if design alterations are made. In addition, lawsuits related to the quantity take-off and cost of construction are frequent; therefore, the calculation of these factors using building information modeling (BIM) has emerged as an alternative. However, existing 2D-based methods are still used more frequently than BIM-based methods for quantity take-offs and construction budgets. This is because of the lack of BIM experience of estimation workers and the absence of a national standard. However, from a designer's point of view, it is necessary to understand the quantity take-off and construction cost based on BIM and accurately create the design according to the budget. In this study, the quantity take-offs of concrete, rebar, and reinforced concrete structures (apartments) in Seoul and Yeongjong were compared with the quantity take-offs based on 2D and BIM methods. From the viewpoint of the designer, we aim to increase the accuracy of BIM-based quantity take-offs.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.17-18
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• 2011

Over the past 20 years, Researchers have tried to develop "Integration Model of Cost and Schedule" in construction industry. They suggested various models and techniques, however, it is still required to develop new methodology for AL Form Work in Public Multi-Housing Projects. Accordingly, this research focused on measuring quantity take-offs of on-going projects and analysing the basic process of using the resources(Labor, Material, Plant) related to cost and time data. There are 3 steps of this research : 1) The literature review of previous studies about Integration Model of Cost and Schedule was conducted. 2) Model for integration between cost and schedule was developed. 3) the accuracy of developed model was verified. The results are expected to improve in integrated managing the cost and schedule data of AL form work.

• Journal of KIBIM
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• v.9 no.2
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• pp.1-10
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• 2019

In this research, schedule optimization is defined as balancing the number of workers while keeping the demand and needs of the project resources, creating the perfect schedule for each activity. Therefore, when one optimizes a schedule, multiple potentials of schedule changes are assessed to get an instant view of changes that avoid any over and under staffing while maximizing productivity levels for the available labor cost. Optimizing the number of workers in the scheduling process is not a simple task since it usually involves many different factors to be considered such as the development of quantity take-offs, cost estimating, scheduling, direct/indirect costs, and borrowing costs in cash flow while each factor affecting the others simultaneously. That is why the optimization process usually requires complex computational simulations/modeling. This research attempts to find an optimal selection of daily maximum workers in a project while considering the impacts of other factors at the same time through OPEN BIM based multiple computer simulations in resource leveling. This paper integrates several different processes such as quantity take-offs, cost estimating, and scheduling processes through computer aided simulations and prediction in generating/comparing different outcomes of each process. To achieve interoperability among different simulation processes, this research utilized data exchanges supported by building SMART-IFC effort in automating the data extraction and retrieval. Numerous computer simulations were run, which included necessary aspects of construction scheduling, to produce sufficient alternatives for a given project.

• Journal of The Korean Digital Architecture Interior Association
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• v.10 no.3
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• pp.11-18
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• 2010

Cost estimation through fast and correct quantity take offs are crucial in the process of construction project. The existing methods for cost estimation are mainly based on 2D-based drawings and the estimation result tends to be different according to the estimator's experience, the quality and quantity of used information and estimation time. To solve these problems, the domestic construction industry have recently tried to use the data extracted from 3D data modeling based on BIM(Building Information Modeling) in order to achieve more accurate and objective cost estimation. However it tends to increase dramatically the quantity of information that can be used in cost estimation by estimators. Therefore in order to achieve quality information data from 3D data modeling, the characteristics of the project should be reflected on the 3D model and it is most important to extract information only for cost estimation from the whole 3D model fast and accurately. Thus this study aims to propose the 3D modeling method through Data Normalization which maximizes the usability of 3D Data modeling in cost estimation process.

• Korean Journal of Construction Engineering and Management
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• v.15 no.4
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• pp.128-138
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• 2014

Development of infrastructure component libraries is a critical requirement for the accelerated adoption of BIM in the civil engineering sector. Libraries reduce the time for BIM model creation, allows accurate quantity take offs, and shared use of standard models in a project. However, such libraries are currently in very short supply in the domestic infrastructure domain. This research introduces library components for retaining walls and box culverts generated from 2D standard drawings made publicly available by MOLIT. Commercial BIM software was used to create the concrete geometry and rebar, and dimensional/volumetric parameters were defined to maximize the reuse and generality of the libraries. Use of the these libraries in a project context demonstrates that they allow accurate and quick quantity take offs, and easier management of geometric information through the use of a single library as to numerous 2D drawings. It also demonstrates the easy modification of the geometries of the components if and when they need to changed. However, the application also showed that some of the rebar components (stirrups and length wise rebars) do not get properly updated when concrete geometries are changed, demonstrating the limits of current software applications. The research provides evidence of the many advantages of using BIM libraries in the civil engineering, thus providing the incentive for further development of standard libraries and promoting the use of BIM in infrastructure projects.

• Korean Journal of Construction Engineering and Management
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• v.14 no.5
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• pp.144-152
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• 2013

Recently construction projects become more bigger. So construction companies have being performed cost and schedule management task by using PMIS. In engineering and construction phase, progress management which occur the most frequent information I/O(input and output) should be managed effectively by PMIS. Although most information by PMIS manage efficiently, cost-schedule information for progress management is difficult to be managed due to recurrent information input. thus when changed by price fluctuation and change order, progress management could not connnect cost information with schedule information. So it caused inaccuracy of progress measurement and data increase in PMIS. To solve this problem, This study suggests improved module for progress management through integration of cost-schedule using quantity take-offs as progress measurement method.