• Magazine of the Korean Society of Agricultural Engineers
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• v.36 no.4
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• pp.73-86
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• 1994

Ths paper was aimed to investigate the effect of reinforcement for the deformation characteristics of clayey foundation. Among numerous improvement method of foundation, only geotextil-reinforced foundation and foundation with both geotextile and sand mat which were 2-dimensional model clayey foundations were selected for load test in order to obtain fundamental results in analizing the behavior of the foundation with geotextile. To scrutinize the behavior characteristics and effect of reinforcement, the model foundations were constructed with various conditions on the location of layout of geotextile, the number of layouts and the depth of sand mat As for the technique of the numerical analysis elasto-plastic constitutive model for clayey soil, beam element for geotextile and elastic model for sand were respectively employed. Interface element was introduced for the block between materials with different rigidity. Observed values and numerical results were compared with satisfactory correspondence, which proved that the numercial technique developed in this paper was available.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.629-637
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• 2010

In this study, we analyzed lateral behavior of connected foundation for transmission tower in clay. For this study, we performed model lateral load test, measured load-displacement curve of connected foundation. For the tests, we manufactured connected foundation model that consider a change of rigidity, installed various measuring sensors for understanding of elements and general foundation behavior. From the test results, we measured load capacities using various methods, compared and analyzed these capacities.

• Journal of the Earthquake Engineering Society of Korea
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• v.26 no.3
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• pp.117-125
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• 2022

In this study, centrifuge model tests were performed to evaluate the seismic response of multi-DOF structures with shallow foundations. Also, elastic time history analysis on the fixed-base model was performed and compared with the experimental results. As a result of the centrifuge model test, earthquake amplification at the fundamental vibration frequency of the soil (= 2.44 Hz) affected the third vibration mode frequency (= 2.50 Hz) of the long-period structure and the first vibration mode (= 2.27 Hz) of the short-period structure. The shallow foundation lengthened the periods of the structures by 14-20% compared to the fixed base condition. The response spectrum of acceleration measured at the shallow foundation was smaller than that of free-field motion due to the foundation damping effect. The ultimate moment capacity of the soil-foundation system limited the dynamic responses of the multi-DOF structures. Therefore, the considerations on period lengthening, foundation damping, and ultimate moment capacity of the soil-foundation system might improve the seismic design of the multi-DOF building structures.

• Journal of Industrial Technology
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• v.22 no.A
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• pp.229-240
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• 2002

This paper is an experimental and numerical work of Investigating the bearing capacity of shallow foundation of rubble mound under eccentric loads. Parametric centrifuge model tests at the 50g level environments with the model footings in the form of strip footing were performed by changing the loading location of model footing, relative density and materials for ground foundation. For the model ground, crushed rock sampled from a rocky mountain was prepared with a grain size distribution of having an identical coefficient of uniformity to the field condition. Model ground was also prepared with relative densities of 50 % and 80 %. For loading condition, model tests with and without eccentric load were carned out to investigate the effect of eccentric loads and a numerical analysis with the commertially available software of FLAC was performed. For numerical estimation with FLAC, the hyperbolic model of a nonlinear elastic constitutive relationship was used to simulate the stress-stram constitutive relationship of model ground and a series of triaxial compression test were carried out to find the parameters for this model Test results were analyzed and compared with Meyerhof method (1963), effective area method based on the limit equilibrium method, and a numerical analysis with FLAC.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.3
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• pp.178-185
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• 2010

This paper presents the evaluation of foundation stability according to decrease of the foundation contact area on the ground. In order to carry out this research, the experimental and numerical studies are performed. In the experimental study, the carefully controled laboratory model tests are carried out with different foundation size and types. The model test results are analyzed and interpreted by analytical and numerical calculation in order to verify both results obtained from experimental and numerical studies. It is clearly found from the results that the foundation stability is considerably reduced when the foundation contact area ratio is less than 75%. This research may be very useful to develop the economical foundation type.

• Magazine of the Korean Society of Agricultural Engineers
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• v.36 no.1
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• pp.83-94
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• 1994

The first part of this study dealt with the determination of soil parameters for Lade's double work-hardening model using the raw data obtained from cubical and cylinderal triaxial tests At present, it should be investigated which test can simulated satisfactorily the behavior of soft clayey foundation. In this regard, plate bearing test on the 2-dimentional model foundation(218cm long, 40cm wide, 19&m high) was performed, and finite element analysis carried out to abtain the behavior of the foundation. Settlement, lateral displacement, displacement vector and mode of failure were measured and these values were compared with numerical values in order to validate the numerical program developed by authors. The FEM technique was based on Christain-Boehmer's method, in which the displacement is obtained at each nodal point while stress and pore water pressure at each element.In this research, Biot's equation, which explains was elahorately the phisical meaning of consolidation, was selected, as a governing equation, coupled with Lade's double surface work-hardening constitutive model.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.2
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• pp.45-52
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• 2016

The object of this paper was to evaulate modified proposed design equation in model test result in order to estimate uplift-resistance of timber pile of reclaimed land greenhouse foundation. Uplift resistance result of model test was increased to according to increased of contact area. Uplift-resistance result of field test tend to lineary increased to according to increased of embedment depth and contact area. Results of field uplift-resistance was evaluate compare with modified proposed design equation results of model test and Effective stress method. As the Effective stress method tend to underestimate, modified proposed design equation results of model test tend to similar type. As the contact area increase, difference between field uplift-resistance results and modified proposed design equation results of model test was considered uplift-speed.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.3-25
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• 2003

In this presentation, soil dynamics for vibrating machine foundation is briefly stated, and the result of a model pile test is presented. Analystical methods used in solving for the stiffness and damping factor for pile-soil system are also treated and the results of the test and the calculated values are compared.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1144-1154
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• 2008

In this paper, the behaviour of shell foundation was studied. In order to perform this study, three studies such as theoretical, numerical and experimental programs were performed. In the theoretical program, the general shallow foundation theories and failure mechanism developed by Terzaghi, Mayerhof and others were reviewed and compared. Based on the previous shallow foundation behaviour, the shell foundation theory was developed using the upper boundary theorem. In the numerical study, the 2 and 3 dimensional FEM simulations were carried out using an uncoupled-analysis approach. From the analysis results, the adequate depth of shell foundation was evaluated. It was also evaluated the bearing capacity according to the shell angle ($120^{\circ}$, $90^{\circ}$, $60^{\circ}$). In the experimental study, the laboratory model tests were carried out for five cases of different foundation shapes including the rectangular and circular foundation in order to verify the theoretical and nemerical study. According to the results of this study, the bearing capacity of shell foundation was theoretically about 15% larger than that of general foundation. However, in the model test, the bearing capacity of shell foundation was about 25 to 30% larger than that of general foundation. In the case of shell angle, the maximum bearing capacity of shell foundation shows when the shell angle of foundation was $60^{\circ}$. In addition, Even if the shell foundation has the various advantages compared with the general foundations as described above, the practical verifications in full scale size will be necessary to use in the field and will be helpful in the technical development of other special foundations.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.1094-1103
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• 2010

The safety of pile foundation is getting declined when the pile foundation acting on lateral load is exposed by dredging. So appropriate reinforcement is needed for stability secure. Thus, in this study, the stability variation and reinforcement range caused by dredging is estimated on the basis of down scale test. The scale effect is determined by real scale numerical analysis. the behavior of pile by dredging stages is estimated by load control type. The credibility is verified through the comparison between down scale model test and numerical analysis.