• International conference on construction engineering and project management
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• 2015.10a
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• pp.712-713
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• 2015

In recent years, the bid-rigging in public construction markets has been treated as a critical issue in Fair Trade Commission. The investigation revealed that the collusion was implemented extensively in every area from the material supply to the construction service of general contractors. This study reviewed the causes of the bid-rigging in public construction projects, and proposed the improvement plan to eradicate bad practices. Firstly, the causes and purposes of bid-rigging were categorized into two types of internal factors from construction companies and external environment factors influencing business activities. Secondly, the system development method was explained to detect the signs of bid-rigging based on the technical proposal documents in open tender. The detection systems of repetitive public owner also provide the function of sharing data on the companies and cases to violate the fair trade regulation. In addition, the problems and improvement direction of public procurement policies were discussed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.172-173
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• 2015

Construction project involves numerous repetitive operations. Especially in high-rise and apartment houses projects, the amount of repetitive operations increase and a preceding operations delay causes serious damage to the total duration of the project. This study deducts work delay factors by site engineer interview and survey. The study analyzes daily report data to deduct crucial processes affecting masonry work which has been investigated to be one of preliminary processes conducted at the beginning of finish work.

• Journal of KIBIM
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• v.1 no.1
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• pp.26-31
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• 2011

Due to the characteristics of 3D objects of building construction projects which have regular, vertical and repetitive shapes, the most practical utilization of BIM in the country is focused on building projects. The characteristics of 3D objects of civil engineering project have irregular, horizontal and non-repetitive shapes. Therefore, consisting of a practical BIM model is difficult comparing with building project. This study suggests an application process of BIM for the planning and design phases for civil engineering project. A BIM system is developed based on suggested BIM process and it is verified through a bridge construction project.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.196-203
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• 2022

The resource constrained scheduling problem (RCSP) constitutes one of the most challenging problems in Project Management, as it combines multiple parameters, contradicting objectives (project completion within certain deadlines, resource allocation within resource availability margins and with reduced fluctuations), strict constraints (precedence constraints between activities), while its complexity grows with the increase in the number of activities being executed. Due to the large solution space size, this work investigates the application of Genetic Algorithms to approximate the optimal resource alolocation and obtain optimal trade-offs between different project goals. This analysis uses the cost of exceeding the daily resource availability, the cost from the day-by-day resource movement in and out of the site and the cost for using resources day-by-day, to form the objective cost function. The model is applied in different case studies: 1 project consisting of 10 activities, 4 repetitive projects consisting of 40 activities in total and 16 repetitive projects consisting of 160 activities in total, in order to evaluate the effectiveness of the algorithm in different-size solution spaces and under alternative optimization criteria by examining the quality of the solution and the required computational time. The case studies 2 & 3 have been developed by building upon the recurrence of the unit/sub-project (10 activities), meaning that the initial problem is multiplied four and sixteen times respectively. The evaluation results indicate that the proposed model can efficiently provide reliable solutions with respect to the individual goals assigned in every case study regardless of the project scale.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.285-286
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• 2012

In the large scale projects, it is difficult to manage every blocks because of the apartment housing project have repetitive shapes and structures. Therefore, it is necessary to divide construction site into work zones and blocks considering site plan, the number of units per each floor, arrangement of blocks, etc. In this study, 20 influencing factors on the grouping of work zones and formwork crew team formation are identified through case study and literature review. Factors are analyzed to determine the degree of influence through experts interviews. A systematic process of crew formation based on work zoning and the considerations by each steps are presented.

• Journal of Construction Engineering and Project Management
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• v.3 no.4
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• pp.1-4
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• 2013

Excavation is most commonly used activity in all construction projects. All contracting agencies prefer to use bigger and heavier excavators and dumpers on site to do excavations if quantity of excavation is huge. Estimation of required number of excavators and dumpers for completion of excavation could be rather a tedious process involving repetitive calculation on which professionals spend their valuable time. As the Information Technology is highly involved in construction section there os need to have IT model for estimation of number of excavators and dumpers. The developed model is useful to calculate required equipments within short period of time. The purpose of the developed IT model is to save the time and efforts of the construction professional. The paper discusses about model which can be used on site to estimate numbers of excavators and dumpers required for completion of certain quantity of excavation within the given time. The calculation considers various existing formulas and method to generate the output. This information could certainly be useful in planning equipments on construction project sites. The tool is user friendly where any non IT background person can use it on construction sites.

• Korean Journal of Construction Engineering and Management
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• v.1 no.3 s.3
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• pp.75-80
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• 2000

In scheduling multi-unit projects, several alternatives can exist in network construction due to repetitiveness of their activities. Project duration is affected not only by the duration of each activity but also by the arrangement of repeating activities in such projects. This paper provides a network compression method that assigns predecessors to each activity to minimize its float time. Different to the previous efforts that utilized line of balance as the base scheduling-model, this research adopts precedence diagram arranged in two coordinates, the space axis and the resource one. This method seeks the most appropriate predecessors for each activity in each direction of the two coordinates for the purpose of minimizing the idle resource and space. This activity arrangement method was applied to a multi-unit apartment-construction project, to prove its capability of network compression. The result shows that the method successfully sought room for saving construction duration by changing the activity arrangement. The network compression method presented in this research can be utilized in multi-unit construction projects such as apartment complex projects.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.169-173
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• 2015

The linear scheduling method or line-of-balance (LOB) is a popular choice for projects that involve repetitive tasks during project execution. The method, however, produces deterministic schedule that does not convey a range of potential project outcomes under uncertainty. This results from the fact the basic scheduling parameters such as crew production rates are estimated to be deterministic based on single-point value inputs. The current linear scheduling technique, therefore, lacks the capability of reflecting the fluctuating nature of the project operation. In this paper the authors address the issue of how the variability of operation and production rates affects schedule outcomes and show a more realistic description of what might be a realistic picture of typical projects. The authors provide a solution by providing a more effective and comprehensive way of incorporating the crew performance variability using a Monte Carlo simulation technique. The simulation outcomes are discussed in terms of how this stochastic approach can overcome the shortcomings of the conventional linear scheduling technique and provide optimum schedule solutions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.110-117
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• 2017

In the construction of high-rise residential buildings in which the finishing works are done repetitively in each housing unit, the construction period and cost can be reduced, while maintaining the quality, if the work process is properly managed in order for the resources to be input continuously. Time management methods such as the Bar Chart, CPM and LOB are not appropriate, due to the difficulties involved in the diagraming of repetitive works and applying them to the project. The Tact method also has difficulties in maintaining a constant work flow and needs significant effort and cooperation from the subcontractors to allocate the resources consistently. Partitioning, base works for finishing, floor mortar plastering and the final finishing work are done sequentially in residential buildings projects, and there are many repetitive activities which differ in terms of the work method, work area and productivity. If these repetitive activities are synchronized or converged toward the last work area, the goal of process management can be achieved effectively. Therefore, a process planning method for the finishing works of residential building projects is proposed, which takes into consideration elements, such as the sequential relation between the activities in each housing unit and classification of repetitive works in terms of their management method, work area and production rate, for the continuous input of resources into the housing units.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.781-787
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• 2009

Training and process analysis in the construction industry has not taken full advantage of new technologies such as building information modeling(BIM). The purpose of this research is to develop a framework for the virtual interactive construction education system using three dimensional technologies. The modules will simulate the construction process for a facility from start to finish using information drawn from real projects in the built environment. These modules can be used as training tools for new employees where they attempt to optimize time and cost in a virtual environment given a limited number of equipment, time and employee options. They can also be used as a process analysis tool for new construction where a number of situational variables can change leading to exposure of potential risk. These modules would be particularly useful for repetitive construction where the initial project is analyzed for optimization and risk mitigation. This paper describes the framework and shows a residential construction example using a 900 square foot wood frame single family house designed for the United States.