• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.549-558
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• 2008

Well known and widely used in urban area and limited installation condition, a low noise and vibration piling method which has being called Bored Prefabricated Piling Method was reviewed in terms of design guide, and introduced a few case as well. Among the areas being applied of that method, a structural guide of architectural foundation was reviewed and compared to civil engineering foundation area to provide wider information for the foundation engineers. With introducing a few case application including pile load testing review especially dynamic testing in normal building foundation work, engineers may have a useful information on the design and construction of the piling method even different engineering area. It may also make enhancement a view of foundation engineering knowledge to various pile foundation area.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.407-414
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• 1999

A simple seismic design procedure for pile foundation using PAR and LPILE$\^$plus/ was proposed. A case of pile foundation under a simple bridge was selected and analyzed. The calculated horizontal movements, shear forces and moments were compared with those evaluated by the numerical exact solutions, and the farmers had similar trends with the tatters.

• 한국지반공학회논문집
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• 제35권8호
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• pp.17-30
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• 2019

실제 시공된 말뚝들의 재하시험 자료 및 매입 PHC말뚝의 설계 자료로부터 전체지지력에 대한 주면마찰력의 분담율인 SRF를 분석하였다. 현장에서 시험 시공된 말뚝의 SRF는 말뚝의 종류, 상대근입길이, 지반의 종류, 재하시험의 종류에 상관없이 42~99%이었다. 매입 PHC말뚝에 대한 설계 자료에서 구한 SRF는 말뚝의 직경, 상대근입길이에 상관없이 풍화암에 소켓된 경우 20~53%의 범위에 분포하였다. 사용말뚝으로 실제 시공된 매입 PHC말뚝에서 재항타 동재하시험 자료로부터 구한 SRF는 말뚝의 직경, 상대근입길이, 지반의 종류에 상관없이 4~83%의 범위에 분산되어 분포하였다. 사용말뚝에서 SRF가 낮은 수준으로 나타나는 이유는 매입 PHC말뚝의 주면고정액의 충전이 제대로 이루어지지 않은 채 시공된 현황으로 볼 수 있었으며 따라서 주면고정액의 시공관리에서 시급하게 개선해야 할 현황이었다. 풍화암에 소켓된 매입 PHC말뚝의 설계에서 사용하고 있는 극한지지력 산정공식으로 계산한 주면마찰력의 SRF는 실제 현장 시공 말뚝의 SRF보다 평균적으로 2.2배 정도로 낮은 수준으로 평가되었다. 이는 설계에서 사용하고 있는 산정공식에 의한 극한주면마찰력이 매우 낮은 수준으로 계산되기 때문이다. 따라서 SRF를 만족시킬 수 있는 새로운 주면마찰력 산정공식의 제안 필요성이 있는 것으로 판단된다.

• Computers and Concrete
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• 제25권1호
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• pp.75-81
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• 2020

The purpose of this paper is to provide an experimental and analytical study on the reinforced large diameter pretensioned high strength concrete (R-LDPHC) pile. R-LDPHC pile was reinforced with infilled concrete, longitudinal, and transverse rebar to increase the flexural and shear strength of conventional large diameter PHC (LDPHC) pile without changing dimension of the pile. To evaluate the shear and flexural strength enhancement effects of R-LDPHC piles compared with conventional LDPHC pile, a two-point loading tests were conducted under simple supported conditions. Nonlinear analysis on the basis of the conventional layered sectional approach was also performed to evaluate effects of infilled concrete and longitudinal rebar on the flexural strength of conventional LDPHC pile. Moreover, ultimate strength design method was adopted to estimate the effect of transverse rebar and infilled concrete on the shear strength of a pile. The analytical results were compared with the results of the bending and shear test. Test results showed that the flexural strength and shear strength of R-LDPHC pile were increased by 2.3 times and 3.3 times compared to those of the conventional LDPHC pile, respectively. From the analytical study, it was found that the flexural strength and shear strength of R-LDPHC pile can be predicted by the analytical method by considering rebar and infilled concrete effects, and the average difference of flexural strength between experimental results and calculated result was 10.5% at the ultimate state.

• Structural Engineering and Mechanics
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• 제55권1호
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• pp.161-189
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• 2015

Soil-pile raft-structure interaction is recognized as a significant phenomenon which influences the seismic behaviour of structures. Soil structure interaction (SSI) has been extensively used to analyze the response of superstructure and piled raft through various modelling and analysis techniques. Major drawback of previous study is that overall interaction among entire soil-pile raft-superstructure system considering highlighting the change in design forces of various components in structure has not been explicitly addressed. A recent study addressed this issue in a broad sense, exhibiting the possibility of increase in pile shear due to SSI. However, in this context, relative stiffness of raft and that of pile with respect to soil and length of pile plays an important role in regulating this effect. In this paper, effect of relative stiffness of piled raft and soil along with other parameters is studied using a simplified model incorporating pile-soil raft and superstructure interaction in very soft, soft and moderately stiff soil. It is observed that pile head shear may significantly increase if the relative stiffness of raft and pile increases and furthermore stiffer pile group has a stronger effect. Outcome of this study may provide insight towards the rational seismic design of piles.

• 한국지반환경공학회 논문집
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• 제20권10호
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• pp.39-46
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• 2019

상부구조물을 지지하는 무리말뚝의 내진설계 시 지반-구조물의 상호작용이 고려되어야 한다. 무리말뚝 설계 시 지반과 구조물의 비선형 관계는 p-y 곡선이 많이 사용되고 있으며 지진과 같은 동적하중조건에서 지반-구조물의 상호작용이 고려된 동적 p-y 곡선을 무리말뚝의 내진설계에 사용하기 위한 연구가 진행되고 있다. 그러나 이와 같은 연구는 말뚝 캡에 의한 지지효과 및 상부구조물의 관성거동에 의한 상호작용은 고려되지 않았다. 이에 본 연구에서는 사질토 지반에 근입된 상부구조물을 지지하는 무리말뚝에서 말뚝 캡의 변화가 무리말뚝에 미치는 영향을 확인하기 위해 말뚝의 배열 및 중심 간격은 고정하고 말뚝 캡 측면과 말뚝 중심 간격을 변화시켜 진동대 모형실험을 수행하였다. 그 결과 무리말뚝에서 말뚝 캡 측면과 말뚝 중심 간격의 변화가 말뚝의 동적 p-y 곡선 및 무리말뚝 효과에 영향을 미치는 것으로 나타났다.

• Earthquakes and Structures
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• 제16권4호
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• pp.455-468
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• 2019

The behavior of pile-deck connections of pile-supported marginal wharfs subjected to earthquake loading is of key importance to ensure a good performance of this type of structures. Two precast-pretensioned pile-deck connections used in the construction of pile-supported marginal wharfs were tested under cyclic loading. The first is a connection with simple reinforcement details and light steel ratio developed for use where moderate pile-deck rotation demands are expected in the wharf. The second is specifically developed to sustain the large rotation, shear force and bending moment demands, as required for the shortest piles in a marginal wharf. Data obtained from the test program is used in the paper to calibrate an equivalent plastic hinge length that can be incorporated into nonlinear analysis models of these structures when prestressed pile-deck connections with duct embedded dowels are used.

• 한국항만학회지
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• 제10권2호
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• pp.69-90
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• 1996

This study is related to save the bearing capacity from using Meyerhof formula namely, static mechanics formula with the S.P.T(N value) of the soft ground and is to choose the soft ground improvement method by the using of total load for the proper method of the pile foundation and then to design the most suitable pile foundation to fit the actual circumstance. The purpose of this study is calculating the diameter of the pile foundation by static mechanics formula and introducing the optimum design condition from the result of the bearing capacity for using N value of the S.P.T obtained from the deep soft ground about the piles such as P.H.C pile, pipe and cast-in-place pile of big diameter, etc. As above-mentioned, it is considered that the use of P.H.C pile or pipe pile is advisable on the synthetical investigation and that the selection of cast-in-place pile method is desirable in terms of the constructive safety and durability.

• 대한토목학회논문집
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• 제33권5호
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• pp.1915-1933
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• 2013

본 연구에서는 단일 현장타설말뚝의 가상고정점을 고려한 해석과 기둥-말뚝을 3차원 전체 모델링한 해석을 비교 분석하여 가상고정점 해석법의 적정성을 평가하였다. 또한, 말뚝 길이, 기둥 및 말뚝 직경, 철근비, 지반조건 등 주요 영향인자에 따라 단일 현장타설말뚝의 거동 평가를 수행하였으며, 이를 통해 가상고정점 해석을 보완한 최적 기둥-말뚝 길이비를 분석하였다. 본 연구결과, 가상고정점을 고려한 해석은 전체 모델링한 해석과 비교하여 침하량과 수평변위를 작게 예측하였으나, 반대로 축력과 휨모멘트는 가상고정점을 고려한 해석에서 크게 나타났다. 따라서 가상고정점을 통한 해석법은 실제 구조물 거동과 다른 단부조건으로 단일 현장타설말뚝의 정확한 거동을 파악하기엔 무리가 있음을 알 수 있었으며, 이에 단일 현장타설말뚝의 정확한 설계를 위해서는 3차원 전체 모델링한 해석이 필요한 것으로 판단되었다. 또한 본 연구에서는 하부 말뚝 길이와 말뚝의 허용 수평변위 관계를 통해 최적 기둥-말뚝 길이비를 분석하였으며, 이를 통해 가상고정점을 고려한 설계를 다소 보완한 경제적이고 개선된 단일 현장타설말뚝 설계를 수행할 수 있을 것으로 기대되었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1707-1711
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• 2008

Landing pier is connect from onshore to offshore with bridge type that a coast structure. The sub-structure is consisted of vertical or batter pile and combined reinforced concrete slab. These days useful design method of quay wall of landing pier type for pile foundation analysis abide by approximate depth of pile supported method, "Harbor and port design criterion, 2005 The ministry of land transport and maritime affairs". The approximate depth of pile supported is calculated two kind of method that one is assume to below depth of 1/$\beta$ from assumed submarine surface and other is 1st fixpoint depth by Chang(1937)'s theory. By this paper, FEM dynamic analysis of 3-dimensions was achieved that it has compared pile fixed end modeling with elastic spring modeling base on winkler theory.