• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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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.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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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.

• Journal of the Korean Geotechnical Society
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• v.35 no.8
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• pp.17-30
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• 2019

Based on pile load test results for various pile types that were constructed in-situ and pile design data of prebored PHC piles, the ratio of skin friction to total capacity (SRF) was analyzed. A SRF distribution range from the pile load test results for pilot test prebored PHC piles was 42~99% regardless of relative penetration lengths, soil types, and pile load test types. However, a SRF distribution range from the pile design data for prebored PHC piles was 20~53% regardless of relative penetration lengths and pile diameters. Also, a SRF distribution range from the restrike dynamic pile load test results for pretest working prebored PHC piles was a scattered range of 4~83% regardless of pile diameters, relative penetration lengths and soil types. The scattered SRF of pretest working piles was caused to the quality control issue on the filling of cement milk around piles and this quality control issue should be improved. The average SRF calculated by the current design method was estimated to be 2.2 times lower than the average SRF of the pilot test piles. It is because skin friction resistance is calculated at a very low level. Therefore, a new design method for skin friction will be proposed based on this study.

• Computers and Concrete
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• v.25 no.1
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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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• v.55 no.1
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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.

• Journal of the Korean GEO-environmental Society
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• v.20 no.10
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• pp.39-46
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• 2019

The interaction between the ground and structures should be considered for seismic design of group piles supporting the superstructure. The p-y curve has been used widely for the analysis of nonlinear relationship between the ground and structures, and various researches have conducted to apply the dynamic p-y curve for seismic design of group piles. This curve considers the interaction between the ground and structures under the dynamic load such as an earthquake. However the supported effect by the pile cap and the interaction by inertia behavior of superstructures. Therefore, the shaking table test was conducted to verify the effect of the change of the pile cap in group piles supporting superstructures embedded in sandy soil. The test condition is that the arrangement and distance between centers of piles are fixed and the length of the pile cap is changed for various distances between the pile cap side and the pile center. The result shows that the distance between the pile cap side and the pile center have an effect on the dynamic p-y curve and the effect of group piles.

• Earthquakes and Structures
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• v.16 no.4
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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.

• Journal of Korean Port Research
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• v.10 no.2
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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.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.5
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• pp.1915-1933
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• 2013

In this study, the virtual fixed point analysis and 3D fully modeling analysis for bent pile structures are conducted by considering various influencing factors and the applicability of the virtual fixed point theory is discussed. Also, the optimized column-pile length ratio is analyzed for supplementing virtual fixed point design and examining a more exact behavior of bent pile structures by taking into account the major influencing parameters such as pile length, column and pile diameter, reinforcement ratio and soil conditions. To obtain the detailed information, the settlement and lateral deflection of the virtual fixed point theory are smaller than those of 3D fully modeling analysis. On the other hand, the virtual fixed point analysis overestimates the axial force and bending moment compared with 3D fully modeling analysis. It is shown that the virtual fixed point analysis cannot adequately predict the real behavior of bent pile structures. Therefore, it is necessary that 3D fully modeling analysis is considered for the exact design of bent pile structures. In this study, the emphasis is on quantifying an improved design method (optimized column-pile length ratio) of bent pile structures developed by considering the relation between the column-pile length ratio and allowable lateral deflection criteria. It can be effectively used to perform a more economical and improved design of bent pile structures.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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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.