• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.512-517
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• 2009

Resistance factors for static bearing capacity of driven steel pipe piles were calibrated in the framework of reliability theory. A comprehensive foundation design case study on an actual bridge was performed using resistance factors developed in this study. Comparing with Allowable Stress Design (ASD), LRFD design method provides quantitative evaluation of safety level of designed foundation and exhibits considerable potential economy in design.

• Journal of the Earthquake Engineering Society of Korea
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• v.25 no.4
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• pp.169-177
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• 2021

In this paper, horizontal seismic responses of a structure built on a sunken mat foundation were compared with those built on a solid embedded mat foundation to investigate the effect of a sunken mat foundation on the horizontal response of a structure. Seismic analyses of a structure laid on the embedded mat foundation were performed by utilizing a pseudo-3D finite element software of P3DASS. Three bedrock earthquake records downloaded from the Pacific Earthquake Engineering Research Center database were scaled to reproduce weak-moderate earthquakes. Weak, medium, and stiff soil layers were considered for the seismic analyses of the structure-foundation-soil system. Parametric studies were performed for foundation radius, foundation embedment depth, and shear wave velocity of a soil layer to investigate their effect on the seismic response spectrum. The study result showed that the design spectrum of a structure built on a sunken mat foundation was similar to that with a solid embedded mat foundation showing a slight difference due to almost the same seismic base motion beneath both embedded foundations.

• International Journal of High-Rise Buildings
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• v.4 no.4
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• pp.271-281
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• 2015

This paper introduces detailed three-dimensional numerical analyses on a bored pile foundation for a high-rise building. A static load test was performed on a test pile and a numerical model of a single pile, which was calibrated by comparing it with the test result. The detailed numerical analysis was then conducted on the entire high-rise building foundation. Further study focused on soil pressures under the base slab of a piled raft foundation. Total seven cases with different pile numbers and raft-soil contact conditions were investigated. The design criteria of a foundation, especially settlement requirement were satisfied even for the cases with fewer piles under considerable soil pressure beneath the base slab. The bending moment for the structural design of the base slab was reduced by incorporating soil pressures beneath the base slab along with bored piles. Through the comparative studies, it was found that a more efficient design can be achieved by considering the soil pressure beneath the slab.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.78-89
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• 2007

Two design examples of deep foundations for high-rise buildings on soft ground are introduced in this paper. The first one is a 54-story building in Ho-Chi-Minh city, Vietnam, which was designed to be founded on $2.8m{\times}1.0m$ barrette foundations with approximately 60m to 75m depth. Based on a number of design guides and existing load test data from the construction sites in Ho-Chi-Minh city, the capacity of a barrette foundation in sand or clay layered ground was calculated to be 17.2MN to 27.8MN depending on the installing depth. The second one is a 40-story building in Baku city, Azerbaijan, which was designed to be supported by 2.0m diameter bored pile foundations with approximately 23m depth. As analytical or empirical guides for the local ground conditions were very limited, the design procedure from the SNiP Code, one of Russian specifications, was adopted and used to calculate the pile capacity. The capacity of bored pile foundation in highly weathered soil was expected to be 14.8MN to 15.5MN depending on the boring depth.

• Journal of the Korean Geotechnical Society
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• v.15 no.5
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• pp.141-155
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• 1999

Korea Ocean Research & Development Institute(KORDI) conducted an offshore geotechnical investigation for the Eardo Ocean Research Station with the help of the Fugro International Limited at a site location approximately 152 km away from Mara Island, Korea. The primary purpose of the geotechnical investigation was to obtain information on soil and foundation conditions, and to develop foundation design data for a fixed offshore observation platform. This paper discussed the details of the geotechnical investigation and the foundation design recommendations for the Ocean Research Station. Clear recommendations were proposed for the foundation type of driven pile considering the existing soil conditions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.2B
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• pp.149-152
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• 2012

This study is carried out to analyze the design method and safety rate degree for IEC 61400-3, DNV-OS-J101, GL Wind, EUROCODE, AASHTO and domestic design standard used for offshore wind turbine foundation design. The findings will provide a design parameter for domestic offshore wind turbine foundation design. The design of the steel Support Structure of an offshore wind turbine can be based on either the Allowable Stress Design(ASD) approach or the Load and Resistance Factor Design(LRFD) approach. The design principles with the use of LRFD method are described with various limit states. A limit state is a condition beyond which a structure or part of a structure exceeds a specified design requirement. Design by the LRFD method is a design method by which the target component safety level is obtained by applying load and resistance factors to characteristic reference values of loads (load effects)and structural resistance. When the strength design of the steel Support Structure is based on the ASD approach, the design acceptance criteria are to be expressed in terms of appropriate basic allowable stresses in accordance with the requirements specified. After comparison an economics domestic offshore wind turbine foundation standard will be developed.

• Journal of the Korean GEO-environmental Society
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• v.16 no.6
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• pp.5-11
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• 2015

Recently the necessity of developing the Load and Resistance Factor Design (LRFD) for shallow foundation has been raised to implement to the domestic design codes related to geotechnical engineering since the limit state design is requested as international technical standard for the foundation of structures. In this study, applicability of LRFD for shallow foundation on weathered soils was investigated and resistance factor for this case was proposed. The quantitative analyses on the uncertainty and resistance bias for shallow foundation on weathered soil ground were performed by collecting the statistical data about domestic case studies for design and construction of shallow foundation. Reliability analyses for shallow foundation were first performed using FDA (First-order Design value Approach) method. Resistance factors were calibrated using the load factors obtained from the specifications of shallow foundations on weathered soil ground. The influence of the load factors developed in this study on the resistance factors were discussed by comparing with the resistance factor obtained from using AASHTO load factors.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.692-700
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• 2007

There are several types of foundations for light-weight structures, such as low story buildings, on soft clay deposits. Those foundations, such as piled raft, compensated foundation, mat foundation, floating foundation are commonly used rather then end-bearing piles to get more benefits on the construction and cost savings. In this study, settlement behaviors are computed and compared for several types of foundations on soft clay deposits. Also, theoretical expressions of parameters for piled raft system were provided with co-relations for design purposes. The predictions of settlements of piled rafts foundation are proposed based on the pile dimensions and design loads. From this study, the piled raft foundations is more benefits for reducing the settlement of clay deposits, and it is found that the piled raft system is applicable and effective on thick clay deposits, and that differential settlements of the foundation should be managed by designing the configuration of pile lengths.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.10
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• pp.882-890
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• 2001

The data link layer of Foundation Fieldbus is operated on the basis of scheduling and token-passing disciplines. This paper presents a network design method of Foundation Fieldbus using a bandwidth allocation scheme. Fieldbus traffic consists of periodic data and sporadically generated time-critical and time-available data. The bandwidth allocation scheme schedules the transmission of periodic data. Time-critical and time-available data are transmitted via a token-passing service. The validity of this bandwidth allocation scheme is determined using an experimental model of a network system. The results obtained from the experimental model show that the proposed scheme restricts the delay of both periodic and time-critical data to a pre-specified bound. The proposed bandwidth allocation scheme also fully utilizes the bandwidth resource of the network system.

• International Journal of High-Rise Buildings
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• v.4 no.4
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• pp.261-270
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• 2015

Hong Kong is a renowned small city with densely placed skyscrapers. It is no surprise that heavy duty or even mega foundations are built over the years to support these structures. To cope with the fast construction pace, several heavy deep foundation types have been widely adopted with some prescribed design rules. This Paper has selected two commonly adopted but distinctive foundation types, namely large diameter bored piles and percussive steel H-piles to illustrate the special design and construction considerations related to these pile types in related to local context. The supervision requirement in related to foundation works for which again may be unique in Hong Kong will also be highlighted. A case history is also discussed in the later part of the Paper to illustrate the application of one of these foundations and to highlight the importance of considering foundation design and basement excavation method in a holistic manner.