• Journal of Korea Water Resources Association
• /
• v.51 no.10
• /
• pp.929-939
• /
• 2018

In North Korea, hydropower which occupies about 63% of power generation is a major electric power source, and North Korea has many advantages in the geographical for developing hydroelectric power. In this study, Information on the basin and dam capacity for 33 potential development site of hydroelectric dam was analyzed using DEM, and potential annual power generation was estimated by applying results of long-term runoff simulation with MWSWAT model for recent 30-year. The potential annual power generation at 33 dam was estimated to be about 28% of the current hydroelectric power in North Korea. In addition, a priority of dam development in each province was assessed by estimating the scale of an industry and prospecting the population change in the future. And a priority for dam development within the province was estimated based on the dam capacity and the potential annual power generation. The priority of each province was ranked in order of Pyeongannamdo, Hamgyungnamdo, Hamgyungbukdo, Hwanghaebukdo, Pyeonganbukdo, Jagangdo, Ryanggangdo, Hwanghaenamdo, and Gangwondo. The results of this study can be used as an initial review data for advancing to hydropower development project in North Korea.

• Tunnel and Underground Space
• /
• v.5 no.4
• /
• pp.308-317
• /
• 1995

The stability study on the rock slope where have produced failures in Boryung dam site was evaluated using the streonet analysis techniques. SMR(Slope Mass Rating) approach which is suitable for preliminary assessment of slope stability in rock was also carried out for rating rock mass. The 3-4 major discontinuity sets are distributed and all type of failure(plane, wedge and toppling failure) are presented in this slope face. The dip of slope must be lowered to friction angle(26degree), otherwise the possibility of plane and toppling faiue will always exist in this slope.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.6A
• /
• pp.607-616
• /
• 2009

In this paper, a method is proposed to accurately and efficiently estimate the equivalent added mass of hydro-dynamic pressure on dam floodgates subjected to earthquake loading. The present method is based on a relatively-simple procedure using on-site vibration measurement and finite element frequency analysis, which is sufficiently practical to be used in the earthquake resistance performance evaluation of dam floodgates.

• Journal of Korean Society of Forest Science
• /
• v.109 no.4
• /
• pp.438-445
• /
• 2020

The characteristics of forest environmental factors were analyzed using the quantification theory (I) for prediction of the suitable area of erosion control dams. The results indicated that sediment discharge in small forest catchments was significantly correlated with dredging passage (0.7495) and age class (0.6000). In contrast, area (0.3416), slope gradient (0.3207), rainfall (0.3160), altitude (0.2990) and soil type (0.2192) were poorly correlated. Following quantification theory (I), we developed a selection decision table for erosion control dams based on sediment discharge rate as class I (highly suitable site, greater than 2.2496), class II (suitable site, 1.1248~2.2495), and class III (poorly suited site, lower than 1.1247).

• Proceedings of the Korean Geotechical Society Conference
• /
• 2003.03a
• /
• pp.359-364
• /
• 2003

For safety evaluation of a rock-fill dim, it is often necessary to investigate spatial distribution of weak zones such as fracture. Both DC-resistivity survey and seismic(SASW) method are usually used for the purpose. Recently, Multichannel analysis of surface waves(MASW) method which makes up for the weak point of SASW method is developed and the site examination which is simple came to be possible comparatively. In order to obtain 2-D shear-wave velocity(Vs) profile along the dam axis that can be associated with dynamic properties of filled materials, MASW method was adapted. Then, DC-resistivity survey and drilling survey were performed to compare with each results. We confirmed that the MASW method and DC-resistivity survey show complementary result that corresspond with drilling result. Therefore, MASW method is an efficient method for dynamic characterization of dam-filling materials and also the combination of related methods such as DC-resistivity can lead to an effective safety evaluation of rock-fill dam.

• Journal of Environmental Science International
• /
• v.23 no.5
• /
• pp.807-817
• /
• 2014

Benthic macroinvertebrates were seasonally sampled from upstream and downstream of the Gunwi Dam construction site from 2006 to 2012. Totally 148 and 165 species were collected at the upstream and downstream sampling sites, respectively. At the upstream area after dam construction, there was no significant change of the numbers of non-insect taxa, but at the downstream area, the non-insect taxon numbers were increased gradually. The individual ratio of Ephemeroptera and Diptera had higher value than the other taxa in both of up and downstream. The trichopteran individual ratios were increased in upstream sites, but decreased in downstream sites from 2010. Also, non-insects and coleopteran individual ratios were decreased in upstream, but increased in downstream after completion of dam construction. The annual range of fluctuation in community indices narrowed after construction. According to a functional feeding group analysis, the individual ratios of FC (Filtering Collector) were increased, and GC (Gathering Collector) and SC (Scraper) were decreased in upstream sites annually. In contrast, the annual individual ratios of FC were decreased, and GC and SC were increased in the downstream sites.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2005.10a
• /
• pp.293-301
• /
• 2005

The CSG(Cemented Sand and Gravel) method is construction technique using as raw materials earth and gravel generated from a local construction site, mixing them with cement and rolling with vibration rollers. Recently, The use of this method for cofferdam and large dam is gradually increasing in Japan. The purpose of an CSG mix design is to develop project specific properties to meet the structure design requirements. But uniform mix design of CSG method has not yet been established. The experience of practitioners from the geotechnical and concrete disciplines has given rise to two genernal approaches to mix design for CSG. This paper reports the concept of how to set the mix design according to modified Proctor compaction test process and the test results on properties such as compaction, compressive strength and modulus of elasticity that obtained by unconfined compression test.

• Journal of Korean Society on Water Environment
• /
• v.27 no.5
• /
• pp.587-596
• /
• 2011

The interest in hydrological modeling has increased significantly recently due to the necessity of watershed management, specifically in regards to lumped models, which are being prosperously utilized because of their relatively uncomplicated algorithms which require less simulation time. However, lumped models require empirical coefficients for hydrological analyses, which do not take into consideration the heterogeneity of site-specific characteristics. To overcome such obstacles, a distributed model was offered as an alternative and the number of researches related to watershed management and distributed models has been steadily increasing in the recent years. Thus, in this study, the feasibility of a grid-based rainfall-runoff model was reviewed using the flood runoff process in the Han River basin, including the ChungjuDam, HoengseongDam and SoyangDam watersheds. Hydrological parameters based on GIS/RS were extracted from basic GIS data such as DEM, land cover, soil map and rainfall depth. The accuracy of the runoff analysis for the model application was evaluated using EFF, NRMSE and QER. The calculation results showed that there was a good agreement with the observed data. Besides the ungauged spatial characteristics in the SoyangDam watershed, EFF showed a good result of 0.859.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.9 no.2
• /
• pp.59-68
• /
• 2009

Currently, building a small dam located 1.16 km downstream from Geumnam Bridge is being considered in order to improve the riverine scenery of the site for Sejong City and to create a hydrophilic space. The purpose of this research is to present the appropriate dimensions of a small dam by reviewing the flood control reliability of the Geum River after the small dam is built. To establish this purpose, changes in the flood water level were compared and analyzed by changing the installation height of a small dam using 1D and 2D models. 1D HEC-RAS and 2D FESWMS models were applied to perform the numerical analysis of the reach. The results showed that flood control reliability was guaranteed when the installation height of the small dam was 5 meters or lower. From the 2D model, a more accurate result can be developed because the model could provide a two dimensional numerical analysis. The results can be used to determine the appropriate dimensions of a small dam for Sejong City.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2008.10a
• /
• pp.869-887
• /
• 2008

Coffer dam for tunnel type spillway in inflow section of Dae-am dam was originally planned as 2 lines sheet piles with Water Zet method. But, the result of pilot test was caused of some problems that vibration during installation of pile could pollute water and water leakage could the lower part. So, sheet piles was not satisfactory for faculty of coffer dam. Structural instability of sheet pile system need to reinforcement. Characteristic of Dae-am dam was small reservoir capacity but wide drainage area, of which it was judgment that security of leakage and stability was difficult during excavation of inlet part. So, we consider that water curtain method utilized with in site pouring concrete pile method was designed at weir part of spillway. We were known about basement rock that geological boring was carried out in weir part. After taking a deep consideration, PRD method was accepted as a new method. Concrete pile by PRD was installed to below country rock. CJM method was carried out with PRD. After making concrete wall using Top-down method, earth anchors were installed for supporting it. According to the result of numerical analysis, as water level rises, wall is stable.