• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.4
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• pp.289-296
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• 2014

The rebar detailing is an important work influencing the final performance and quality of RC structures. But it is one of the most irrational and illogical activity in construction site. Many groups of workers, including main contractors, structural engineers, shop drawers, rebar fabricators, and etc., participate in this activity. A loosely-organized process for this activity is apt to produce a big amount of rebar loss or even degraded structures. A 3-dimensional rebar auto-placing system, called as Rebar Hub, has been designed and implemented in this research. Rebar Hub provides a totally integrated service from 3D structural modeling of buildings to rebar auto-placing considering anchorage, splice, and the length of ordered rebar. In addition, Rebar Hub can recognize the 2D drawing CAD files and then build 3D structural models which are used for the start point of 3D rebar auto-placing. After rebar auto-placing, each members of the 3D structural model have rebar information belonging to them. It means that the rebar information can be used for the afterward works such as quantity-survey, manufacturing and fabrication of rebars. Rebar Hub is showing outstanding performance while applying to practical projects. It has almost five times productivity and reduces the rebar loss up to 3~8% of the initially-surveyed amount of rebar.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.1
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• pp.121-132
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• 2018

Korea's construction engineering companies are facing difficulties in deterioration of international construction profitability because they focus on traditional engineering fields such as design and construction supervision. Therefore, it is necessary to strengthen competency of high-add-value engineering field such as Project-Management-Consultancy (PMC). This paper aims to suggest the strategies to enhance the international PMC competency. This study identified the competency factors for international PMC, using Borich needs assessment and Locus for focus model. As a result, step-by-step strategies were suggested according to the competency level in domestic engineering companies. The results of this study will assist Korean engineering companies to consider the important competencies for international PMC projects. Furthermore, enhancement strategies are going to be proper references for domestic engineering companies which prepare the international PMC project.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.4
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• pp.463-469
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• 2011

BIM(Building Information Modeling) technologies should be applied for the construction life cycle to maximize its efficiency, but the utilization for the construction phase has been significantly lower than that for the planning and design phase. Recently, some of BIM techniques such as 3D design review, 4D schedule management and so on are being introduced for efficient managing to the big national construction projects. In this study, the utilization plans of BIM are presented for the construction phase of civil engineering facilities. The methods of utilization of BIM are discussed for each type of construction, and the techniques applied to the Seoul Subway Lot No. 919 are analyzed for checking the applicability and usability. In particular, a web construction management system based on BIM can help field engineers, headquarters and contractors to use BIM more effectively, and it can be extended to maintenance phase for more efficiencies.

• Journal of the Korea Institute of Building Construction
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• v.24 no.1
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• pp.133-144
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• 2024

The OpenCV-based length measurement algorithm is anticipated to be effective for length measurement inspection tasks, providing objective inspection outcomes. Nonetheless, there is a notable gap in research regarding the influence of various checkerboard types and capturing conditions on the algorithm's accuracy in real-world construction settings. Consequently, this study proposes a methodology employing an OpenCV-based length measurement algorithm and checkerboard for digital construction inspection tasks. The findings suggest that using a checkerboard with square sizes of A4 or larger, and 50mm or larger, is optimal for capturing distances and angles within 4m and 90°, respectively, when deploying the algorithm. These insights are anticipated to provide practical guidelines for professionals conducting digital-based length measurement inspections.

• Korean Journal of Construction Engineering and Management
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• v.11 no.2
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• pp.94-105
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• 2010

Recently, resettlement problems of low income groups in the urban regeneration area have been issued in Korea because they have no capability to purchase (or lease) redeveloped housing (or apartment). There are several approaches for supplying affordable housing and one of these is the bidding system which can reduce construction cost. However, the lowest bidding system has many problems such as dumping and substandard quality. In this context, this study proposed bidding system based on technical proposal applying the concept of the lowest total combined bid price for optimization of bid price, reduction of construction cost and period, and maintenance of suitable quality. This bidding system embraces the best value and cost plus time concept on the basis of an improved lowest price bidding system. It consists of the following components: work unit based, project unit based, and period reducing technical proposals. The proposed bidding system for determining bidders are designed to evaluate the adequacy of each technical proposal in the order of the combined minimum price in an effort to effectively optimize bid prices and reduce the construction periods, as well as to maintain a minimum appropriate quality.

• Korean Journal of Construction Engineering and Management
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• v.17 no.1
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• pp.10-17
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• 2016

Domestic CM market has continued to grow since the enactment of CM policies in 1996. In addition, future CM market is forecasted to have potential high growth. Therefore, it is necessary to apply various CM business models reflecting the owner's requirements and characteristics in order to improve in the CM industry and to strengthen the competitiveness in the overseas construction market. In this context, the purpose of this study is to suggest strategies of various CM applications based on comparison of 4 cases analyzed by 'business weight' and 'business depth' in terms of business function as well as by the types of 'CM market' and 'CM practice'. Result of this comparative analysis shows that each case presents differences in terms of type, business weight, and business depth of CM practice. However, domestic public CM services are currently being challenged to strengthen capability throughout the project life-cycle against the limitation of government's CM policies focused on the construction supervision. In order to address this problem, this study proposes the strategies of various CM applciations from several different perspectives

• Korean Journal of Construction Engineering and Management
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• v.20 no.1
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• pp.32-40
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• 2019

This study analyzed operating condition and the problems of damage compensation insunace (property insurance) for qualified architect and derived some suggsetions for improvement. The Certified Architects Act requires all building design and construction supervision to buy property insurance. This study proposes following suggestions to solve problems of current architect property insurance. Firstly, we need to increase the insurance purchasing rate of damage compensation insurance for qualified architect. It is necessary to clearly specify the matters concerning the submission of insurance policies by the architects, which is currently carried out by the Minister's official letter, in the form of official announcement. Secondly, proper insured amount should be adjusted. In order to insured substantial compensation capacity, total amount of insurance should be enlarged. Thirdly, the insurance period should be extended to one year after completion of building to allow compensation for accidents due to design negligence. Generally, the design defect can mostly be identified within one year after completion. Fourthly, insurance coverage should be extended. In the long run, it is essential to enlarge the scope of the security not only to property damage but also to human losses. Finally, an accident record sharing system should be established among insurance companies, so that proper insurance premiums or discounts can be made based on the system.

• The Journal of Engineering Geology
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• v.28 no.4
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• pp.605-618
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• 2018

Korea follows the slope design criteria during construction. It was enacted by the Ministry of Land, Transport and Maritime Affairs. There are cases where the Soil-nail is designed as a measure to secure slope stability. The arrangement of the soil-nail may be arranged at equal intervals or may be arranged differently depending on the soil failure model. The optimum design of the countermeasure method is determined by securing stability of the slope through optimization of dimensions and shape. However, when uniform nails are placed at low elevations in slopes, the standard safety factor is exceeded, which may hinder economic design. It is preferable to arrange the reinforcement of the nails over the entire slope. When the horizontal spacing of the nails was topology optimized according to the slope height, it was possible to minimize the amount of reinforcement while satisfying the standard safety factor. Since the active load is reduced in the section where the slope height is lowered, the safety factor after reinforcement may be excessively increased. Therefore, the phase optimization method is proposed as an economical optimal design method using the reinforcing shape density. In addition, a relational expression was designed to optimize the horizontal spacing by slope height.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.2
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• pp.47-61
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• 2009

The purpose of this study was to understand the laws related to the safety management of children's play facilities(LRSMCPF) including the "Safety Supervision Law of Children's Play Facilities(SSLCPF)" and the "Quality Management and Industrial Products Safety Management Law(QMIPSAL)", in order to analyze the problems by 4 phases-development of products, landscape design, landscape construction and maintenance considering landscape project procedure-and to propose a revision of the laws. The results are as follows: 1. The various LRSMCPF, SSLCPF and QMIPSAL, as basic laws for the safety management of children's play facilities, were insufficient regarding the features of children's play facilities and play spaces, which are both comparatively varied and complex. 2. In development of products, the one-year duration of safety certification based on QMIPSAL was too short and the procedure for safety certification were redundant in both products and plants inspection, and export and import product inspection. 3. The field inspection of construction sites based on SSLCPF was repeated with quality control and a consultation of rules based on "Construction Technology Management Law". 4. There are not enough safety inspection organizations regarding children's play facilities to meet the demand of safety certification, safety inspection, and safety education in the near future. 5. For children's play safety, the establishment of a general safety management system for children's play connected with the phases is needed to ensure safe play equipment, to construct safe playgrounds, and to manage play facilities. The criteria, regulations, and procedure regarding safety certification and safety inspection of play facilities must be revised efficiently and standardized to a global level as well. To improve the system and contents of safety certification and inspection, authorization of safety inspection organizations based on landscape architecture is needed. Further study will be required to concretely analyze in detail the laws, enforcement decrees and rules, and ordinances that consider the practical experience of professional landscape architects, inspectors, and lawyers.

• Korean Journal of Construction Engineering and Management
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• v.10 no.5
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• pp.37-46
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• 2009

This research will focus on the public agencies, designers, supervisors, building cooperation, and contractor who involved in urban development plan. By understanding the complexity and the priorities in urban development process, all problems of the urban development projects can be solved or improved. These priorities are specified using AHP (Analytic Hierarchy Process). A questionnaire survey is employed to identify the problems of urban development process and the methods of revitalizing urban in this research. Through the survey, 35 issues are drawn out. Factor analysis technique is applied to extract the underlying interrelationships possibly existing. Using latent root criterion and varimax rotation method, 9 factors are extracted(by using 34 issues after deleting 1 issue less than 0.4 of factor loading) These 9 factors named as PIF (Problem Improvement Factor) consist of integration estimation (PIF1), cooperation operation capability (PIF2), contractor corporation capability (PIF3), capital for infrastructure investment (PIF4), misunderstanding of effective land use (PIF5), financial capability (PIF6), obscure goal of project (PIF7), shortage of cooperation expertise (PIFS), administrative procedures (PIF9). PIF 6 is the most important factor and PIF 1 is the most widely effective factor to succeed urban land development projects. It is recognized that administrative office is most responsible for PIF1 cooperation is most responsible for PIF2, 7, 8 and 9; contractors is most responsible for PIF3 and PIF6; administrative agencies is most responsible for PIF4; cooperation and consultants are responsible for PIF5. From findings in this study, some suggestions are proposed for the revitalization methods of urban development projects through the land readjustment method.