• 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.

• The Journal of Engineering Geology
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• v.16 no.1 s.47
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• pp.97-107
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• 2006

Or this study, prevailing design and construction methods of dam under various unfavorable conditions are summarized. for example, foundation treatment with large scale alluvium site or weathered rock mass, dam constructing techniques with unfavorable topographic conditions are studied for the better understanding of relating engineers. Also, zoning by using weak rocks and sand-gravel fill techniques are summed up.

• Journal of the Korean GEO-environmental Society
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• v.9 no.7
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• pp.53-60
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• 2008

The purpose of this study is to make case studies on estimation of shear wave velocity in core zone of some rockfill dams by MASW (Multi-channel Analysis of Surface Waves) and to compare the results of case studies with those of the empirical method. Furthermore, the purpose is to recommend the range of shear wave velocity in core zone by MASW and to supply the preliminary data for estimation of shear wave velocity in core zone which is needed for dynamic analysis. From the results of case studies and the comparison between the results of case studies and those of empirical equation, it was found that the shear wave velocities obtained by MASW were smaller than those by the empirical recommendation (Sawada & Takahashi) in the depth of more than 10 m. Also, it is recommended that using the lower bound of empirical formulation by Sawada and Takahashi be available and resonable in case that MASW is not available due to the field condition and the investigation is preliminary.

• 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.

• Journal of the Korean Geotechnical Society
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• v.21 no.7
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• pp.31-42
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• 2005

In this study, a rockfill-dam material was investigated on its shear strength and compressibility by performing large-scaled triaxial and oedometer tests. The rockfill material was compacted at two different compaction levels and sheared in triaxial compression at three different confining stresses. Also, rockfill samples were prepared to have three different grain size distributions but the same dry density. Each sample with a given grain size distribution was then compressed one-dimensionally in a large-scaled oedometer cell with and without soaking. The rockfill samples exhibited slightly different shear behaviors with the varying compaction and confining stress levels. The increase in the compaction level changed the behavior from contractive to dilative. Dilation decreased gradually with increasing confining stress, resulting in reduction in the peak shear strength. The large-scaled oedometer test results showed that particle breakages increased with increasing average particle sizes of the samples. Comparing the samples with different gradations, a relatively well-graded sample exhibited lower compressibility. For saturated samples, slightly higher deformations were observed, compared to dry samples. The values of tangent constrained modulis for the dry samples were larger by about 10 to 20$\%$, on the average, than those for the saturated samples.