• The Journal of Engineering Geology
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• v.2 no.1
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• pp.19-35
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• 1992

aThe elastic properties of the fault zone (width; 3~12m), the shattered zone (width; over 40m) and the fresh rock zone distributed under the core foundation of fill dam in granitic gneiss have widely different range. The deformation moduli of the fresh rock zone, the fault zone and the shattered zone obtained from in situ rock tests - Plate Load Test and Bore Hole Deformation Test - show a range of $42,000~168,000kg/\textrm{cm}^2,{\;}963~2,204kg/\textrm{cm}^2{\;}and{\;}1,238~2,098kg/\textrm{cm}^2$, respectively. The differential settlements hetween the fault zone and the fresh rock zone are expected after the dam construction. Therefore, the displacement of foundation and concrete fill are evaluated using FEADAM 84 program of finite element analysis. The geometric distribution of discontinuifies obtained from the site mapping and drilling is considered in the finite element analysis. The analysis shows that the differential settlements between the fault zone and the fresh rock zone is about 6cm, while that of concrete fill is within 0.5cm.

• Journal of the Korean Geotechnical Society
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• v.25 no.12
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• pp.69-85
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• 2009

It is very important to measure reliable dynamic properties of each zone in dam for seismic design. However, the Vs values of core and rock-fill zone are seldom determined by field test. Consequently, seismic design in dam is performed using Vs values assumed or empirically determined. So, it is required that reliable Vs has to be evaluated by in-situ test. In this study, surface wave method, which is nondestructive, was applied to dam to evaluate Vs profiles of core and rock-fill zone in dam. In 6 dams, using SASW and HWAW methods, Vs profiles were evaluated reliably. D/B of Vs profiles of each zone with depth and relationship between confining pressure and Vs profiles of rock-fill zone were constructed including existing results of other dams. The evaluated D/B and proposed relationship were compared with the frequently used empirical method by Sawada and Takahashi.

• Geophysics and Geophysical Exploration
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• v.13 no.1
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• pp.9-23
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• 2010

In current design practice, the shear wave velocity (Vs) of the core and rock-fill zone of a dam, one of the characteristics essential for seismic response design, is seldom determined by field tests. This is because the borehole seismic method is often restricted in application, due to stabilisation activities and concern for the security of the dam structure, and surface wave methods are limited by unfavourable in-situ site conditions. Consequently, seismic response design for a dam may be performed using Vs values that are assumed, or empirically determined. To estimate Vs for the core and rock-fill zone, and to find a reliable method for measuring Vs, seismic surface wave methods have been applied on the crest and sloping surface of the existing 'M' dam. Numerical analysis was also performed to verify the applicability of the surface wave method to a rock-fill dam. Through this numerical analysis and comparison with other test results, the applicability of the surface wave method to rock-fill dams was verified.

• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.101-106
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• 2008

It is very important to measure reliable properties of each zones in dam for seismic design. But, rock-fill zone which have 80% of total volume and support maintenance mainly during earthquake has little property by field test and seismic design was performed using assumed value. So, it is required that reliable properties have to be evaluated by in-situ test. In this study, surface wave method, which is nondestructive such as SASW and HWAW, was applied to dam to evaluate rock-fill zone of dam. In 2 dams, Vs profiles were evaluated reliably and possibility of suggestion of D/B was verified.

• Journal of the Korean Geotechnical Society
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• v.35 no.2
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• pp.29-36
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• 2019

There always exist the spatial variations of material properties such as a shear wave velocity in a dam and between same type dams. These uncertainties cause those in evaluation of a shear wave velocity profile of a dam and should be considered in determining the shear wave velocity profile for a rockfill zone of a fill dam. In this paper, these uncertainties of a shear wave velocity in the rockfill zone of the fill dam in Korea are evaluated. And the shear wave velocity profile model considering these uncertainties in rockfillzone is proposed using the method based on Harmonic wavelet transform. The proposed shear wave velocity profile model is compared with Sawada-Takahashi model widely used for evaluation of a shear wave velocity profile of a rockfill zone of fill dams.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.5
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• pp.1-9
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• 2009

In this study, the properties of shear wave velocity of coarse gravel in filldams are analyzed. Shear wave velocity is derived using the surface wave analysis method, which can be used nondestructively on the surface of filldams. These values are acquired through the tests for the rock zone of six filldams by SASW and HWAW methods. These analytical results are compared with results obtained through the frequently-used empirical method of Sawada and Takahashi.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.871-876
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• 2010

When surface Concrete Face Rock fill Dam constructs than existent center core type rock fill dam, it is much prevalent form in domestic these day by quality control of that is profitable and weather condition etc. of coreZone. C.F.R.D is less research about seismic survey(Refractional Seismic Prospectin, Resistivity Prospecting) of levee body than fill dam. Thus as C.F.R.D seismic survey is less, safety of that consist is short most development flue is high reason. That is not checking target of minuteness safety diagnosis and so on by short operation period. Wish to analyze inquiry incidental and difference with center core type dam and acquire C.F.R.D preservation administration upper necessary inquiry condition forward hereafter.

• Journal of the Korean Geosynthetics Society
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• v.12 no.1
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• pp.63-72
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• 2013

The structural stability of fill dam largely depends on the engineering behavior of rock materials used as main zone for dam construction and it is necessary to understand well the stress-strain characteristics of fill materials as well as shear strength property. In addition, the numerical analysis of fill dam requires a thorough study for calibrating material properties and parameters of a coarse-grained soil constitutive model. In this paper, large triaxial test results for Buhang-dam fill materials are analyzed and constitutive model parameters are calibrated based on the test results. It is shown that MD constitutive model is capable to predict the stress-strain behavior of dense and loose coarse-grained soils used for Buhang-dam construction based on the comparison study between the experimental test result and numerical simulation.

• Journal of the Korean Geotechnical Society
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• v.36 no.4
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• pp.31-39
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• 2020

Shear wave velocity (or shear modulus) is very important in the evaluation of seismic performance of a fill dam under an earthquake. A shear wave velocity profile can be determined by surface wave method such as HWAW and SASW methods but this profile has uncertainty caused by spatial variation of material property in a fill dam. This uncertainty in shear wave velocity profile could be considered using a coefficient of variation of material property in the reliability based analysis. In this paper, the possible 600 shear wave velocity profiles in the core and rockfill zone of fill dam were generated by the random shear wave velocity profile generation method, proposed by Hwang and Park, based on the field shear wave velocity profiles determined by the HWAW and SASW methods. And, through the statistical analysis of generated shear wave velocity profiles in the fill dam, the coefficient of variation (COV) of shear wave velocity with depth were evaluated for the core and rock filled zone of fill dam in Korea.

• Journal of the Korean GEO-environmental Society
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• v.16 no.8
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• pp.21-35
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• 2015

Electrical resistivity survey (2D and 3D) were employed for detection of possible weak zone of core zones of three central core earth-rockfill dams in Korea. In the 2D results, the core zones is lower resistivity zone with less than $50{\sim}400ohm{\cdot}m$, and the basement is relatively higher resistivity zone with over $1,000ohm{\cdot}m$. In the 3D results, especially, the weak zone with under $100ohm{\cdot}m$ was detected spatial distribution area in the dam. We also drilled boreholes to collect soil samples of core zones of each dam. Water was not used during boring, because water for rotary wash boring could cause structural damages in earth dams. We found that the soil samples of core zones from all of the boreholes correspond to CL (USCS), but we also found that the fluidized or water-saturated soil samples were found in lower resistivity zones. Therefore, the electrical resistivity survey and drilling method without water are a quick and efficient method for structural-health evaluation which is detection of possible weak zones in earth core rockfill dams.