• Journal of the Korean Geotechnical Society
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• v.18 no.3
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• pp.87-94
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• 2002

Recently, there have been numerous attempts to expand the traditional temporary soil nailing system into a permanent wall. Two reasons for this include the soil nailed system's advantage of efficient and economic use of subgrade space and its ability to decrease the total construction cost. However, the systematic and logical design approach has not been proposed yet. The permanent soil nailing wall system, which utilizes precast concrete from soil nailing system, is already used in many countries, but the study of cast-in-place concrete lacing or rigid walls in bottom-up construction of traditional soil nailing walls is imperfect and insufficient. In this paper, various laboratory model tests have been carried out to investigate the influence of parameters, including stiffness of the rigid wall to the soil nailing structure with respect to failure mode, displacement patterns and tensile forces at the nail head in several levels of load. Then, the variation of earth pressure distribution on the soil nailing wall, built with a rigid front plate, is sought through different levels of surcharge load and tensile forces at the nail head.

• Korean Journal of Construction Engineering and Management
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• v.24 no.2
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• pp.24-36
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• 2023

OSC is drawing attention to supplement limitations such as productivity problems and on-site safety and quality problems of existing on-site labor-oriented construction production methods. In order to activate the introduction and use of OSC in the domestic construction market, it is important to innovate the technology applied to each stage of OSC process (design and engineering, factory manufacturing, site assembly, and maintenance), but it is also necessary to develop a project management method suitable for OSC method. However, research related to OSC currently being conducted in Korea is mainly in terms of related technology development, and research on deriving project management measures for the success of OSC projects is insufficient. Therefore, it is time for research on deriving a project management plan based on the core success factors of the OSC project. Therefore, by conducting importance-performance analysis on 69 OSC critical success factors derived from the previous study, the study was conducted to derive key improvement factors for OSC introduction and utilization improvement and to provide implications for this. The results of this study are expected to have useful implications for the R&D planning and policy-making process for OSC activation in the future.

• Korean Journal of Construction Engineering and Management
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• v.22 no.6
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• pp.55-63
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• 2021

Recently, as the problem of the traditional on-site labor-intensive construction production method has been raised due to changes in construction work labor and site conditions, the OSC method is gradually spreading as an alternative to this. Even in apartment houses, the application of the PC method is expanding centered on the underground parking lot, but the high cost structure is a problem compared to the conventional formwork method. In this study, factors affecting the calculation of construction cost in the economic evaluation, which are the core of determining the construction method for apartment buildings, are derived through domestic and foreign literature review and expert advice, the importance was analyzed through an opinion survey targeting industry experts. The measures to reduce construction cost were mainly derived from the improvement of the design and manufacturing process. It is expected that the factors affecting the construction cost and improvement measures of the PC method derived from this study will serve as a direction for technology development to spread the application of the PC method for apartment houses in the future.

• Korean Journal of Construction Engineering and Management
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• v.22 no.6
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• pp.96-106
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• 2021

The PC structure based on the OSC (Off-Site Construction) is mentioned as a representative method of innovation in the construction industry that converts the existing construction environment from site-centered to factory production-transportation-site assembly. However, recent research on PC method has focused on improving the functions of subsidiary materials and improving the production system to increase productivity and institutional / policy R&D that can be universally applied to the life-cycle stage of ordering / design /construction is insufficient. In particular, the absence of standardized cost calculation standards makes it difficult to calculate and verify of objectified appropriate construction cost. So which is an obstacle to the activation of the PC method. In this study, the standards for construction costs of domestic and foreign PC method were surveyed and similar Construction Standard Production Rates were analyzed to confirm the product structure suitable for PC method. Subsequently, the construction procedures and input resources for each PC subsidiary materials were identified through on-site surveys to derive component for subsidiary materials, and the factors of change in the product according to the construction characteristics(height, weight of subsidiary material) were verified. As a result the standard product calculation system suitable for the site installation of the PC method for apartment was presented.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.1
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• pp.113-122
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• 1999

The importance of the vertical response of a structure was well recognized after the Hyogoken-Nanbu earthquake of Japan. However, most of the seismic design codes does not specified the site sail profiles, and the sail and foundations conditions were mostly neglected in the vertical seismic analyses of a structure. In this paper, the effects of foundation size, sail layer depth under the foundation, foundation embedment and pile foundation on the vertical seismic response spectra for both surface and embedded mat foundation were studied to investigate the effects of the soft soil layer on the vertical response of a structure excited with the vertical components of Taft and El Centro earthquakes, considering the sail profile types of $S_A,S_C,S_E$ in UBC-97, the medium and large size foundations, the soil layer depth under the foundation of 30 and 60m, the foundation embedment of 0 and 15m, and the precast reinforced concrete bearing piles installed in the soft soil deposit. According to the study results, the foundation size has a little effect on the vertical seismic response, However, the soil layer depth under the foundation of 60m has to be considered for the vertical seismic analysis of a structure as for the horizontal one. The embedded pile foundations as well as the surface ones built on the soft soil layer amplified the vertical seismic response of a structure very much.