The river levees along the state owned rivers or local rivers are a major infrastructure of the nation, and it is necessary to be able to quickly and accurately evaluate the safety of each structure in case of a disaster such as flood or earthquake, so as to enable preemptive disaster response. In this study, a “real-time safety assessment method of river levees” was developed to understand the safety of river levee in real time and cope with disaster situations preemptively and effectively, and its applicability was examined. The real-time safety evaluation method of the river embankment developed in this study is based on two systems; ① real-time monitoring system by instruments and ② safety evaluation DB system of river embankment based on fragility curves using numerical analysis results. In order to validate its applicability, the safety of Munsan levee located in the upstream area of Kangjeong-Goryeong Weir was evaluated by applying the proposed method.

A series of disaster response drill was conducted using a robust and integrated safety management platform (WINS+) which can provide multi-functions of safety evaluation in realtime, disaster information provision and recovery actions for major water infrastructures, which are designated as nation’s first class infrastructures, under natural disasters such as floods or earthquakes. It is believed that the experience of disaster response drills using the new integrated safety management system (WINS+) enhances our capability of preparedness and response against disasters, and that the validity of WINS+ can be clearly confirmed.

중공슬래브는 휨 성능에 영향을 미치지 않는 부분의 콘크리트 단면을 삭제하고 중공재로 치환함으로써 중공재 부피만큼 콘크리트가 줄어들어 자중 감소효과를 가져오는 장점이 있다. 또한, 콘크리트의 물량절감뿐 아니라 친환경적 측면에서 이산화탄소의 배출도 저감할 수 있어 효과적이다. 하지만, 중공재로 치환한 부분의 지압강도가 명확하지 현장 적용 시에 여러 가지 문제점이 발생한다. 이에 본 연구에서는 중공재가 포함된 중공슬래브를 제작하여 각 타입별(트럭 하중 적용 시, 동바리 하중 적용 시 및 잭 서포트 하중 적용 시)로 국부지압강도 실험을 수행하여 중공슬래브 국부 지압강도의 안전성을 평가하고자 한다. 트럭하중 적용 시, 동바리 하중 적용 시 및 잭 서포트 하중 적용 시의 실험결과 중공재 연결부위 및 중공재 상부의 지압강도는 모든 실험체에서 허용 하중 이상을 보유한 것으로 나타났다. 또한 데크 적용 유무에 따른 실험결과도 모두 허용 하중을 초과하여 안정성을 확보하는 것으로 나타났다.

Numerical analysis using commercial CFD code was carried out to develop the drag force type vertical axis hydraulic turbine for the improvement of the production efficiency of small hydro energy at low flow velocity condition. Blade pressure changes and internal flows were analyzed according to the presence or absence of the hydraulic turbine blade holes at flow velocity of less than 1.0~3.0 m/s. According to the numerical results, the pressure and flow velocity is severly affected by the flow velocity in turbine blade with no holes, while the influence of flow velocity is comparatively decreased in turbine blade with holes. It is also found that the pressure and flow velocity on the blade surface with holes are evenly distributed with no singular location and it is believed that forming a hole in the blade may be helpful in terms of structural safety.

In this study, hydrological safety vulnerability assessment on dam facilities was estimated using dams' hydrological safety evaluation result and in-depth inspection assessment result and considering climate change scenario. Hydrological safety assessment of the existing dam was performed by calculating the pmp/pmf using the climate change scenario. Using the results, Multi-Criteria Decision Making was used for vulnerability ranking decision on dams, and assessment scores and weights of hydrological safety evaluation considering climate chage were applied as payoff matrix and weight coefficient. In this study, it was evaluated vulnerability ranking that hydrological safety evaluation of existing dam considering climate change.

This paper aims to evaluate the safety of the cable supported bridges under the occurrence of damages on cable system. There are more than 50 cable supported bridges currently built in the Korean peninsula and efficient and systematic maintenance and management are in great demand. However, safety of the bridges cannot be under estimated and should be properly evaluated. In this paper, two bridges (one cable-stayed bridge and one suspension bridge) in South Korea were investigated their safety based on the damage scenario of cable system. FEM analysis for safety evaluation of the two bridges was conducted and the results were explained. The result could be used by operators and owners of bridges for the future maintenance and management.

The safety issue of PSC box Girder Bridge is being brought up to the surface. For countermeasures, we developed an extensive material testing procedures and applied it into our existing bridges. We believe that these set of newly constructed procedures are well within the reasonable mark. With that, we now foresee the necessity in systematic improvement and ample supply of its technology in order to secure the future safety of PSC box girder bridges.

We have studied the optimum location of the sensor to evaluate the condition of the structure by performing the structural analysis on the landing pier. It is judged that it is appropriate to place the strain sensor of the landing pier at the upper part, the middle part and the upper part of the pile at 30% below the pile.

The safety issue of PSC box Girder Bridge is being brought up to the surface. For countermeasures, we developed an extensive material testing procedures and applied it into our existing bridges. We believe that these set of newly constructed procedures are well within the reasonable mark. With that, we now foresee the necessity in systematic improvement and ample supply of its technology in order to secure the future safety of PSC box girder bridges.

We have studied the optimum location of the sensor to evaluate the condition of the structure by performing the structural analysis on the landing pier. It is judged that it is appropriate to place the strain sensor of the landing pier at the upper part, the middle part and the upper part of the pile at 30% below the pile.

Background : Recently, many studies to seek for medicinal herb compounds from natural products have been attempted capable of being free from harmful side effects and reducing the economic burden. This study was conducted to investigate whether Morus alba L.(MAL) water extracts has a biological safety, and an inhibitory potential against the mutagenicity induced by cigarette smoke condensates(CSC). Methods and Results : MAL was extracted with 70% ethanol and the yield of the extract was 35.1%. The 70% ethanol MAL extract was fractionated sequentially by diethylether, chloroform, dichloromethane, and water, respectively. Crude MAL 70% ethanol extract itself and its solvent fractions did not show any mutagenic effect up to 1 mg/plate toward Salmonella typhimurium TA 98 with or without the microsomal S-9 mixture of liver metabolic activations. On the other hand, the crude MAL extract showed an inhibitory activity against the mutagenicity of CSC with S-9 mixture. Diethyl ether layer among five solvent fractions showed the highest inhibitory activity at the same dose. The inhibitory activity of diethyl ether layer was also increased dose-dependently and the inhibitory rate was about 97.1% at the concentration of 1 mg/plate. Conclusion : In this study, we concluded that all of the crude MAL 70% ethanol extract and its solvent layers are potentially safe for mutagenicity and the diethyl ether layer among the crude MAL 70% ethanol extract has an inhibitory effect against the mutagenicity of CSC.

There has been a growing interest in the seismic performance of existing structures. Have been enacted most of the evaluation criteria, there is a need for specific seismic performance evaluation methods and standardization of the dam. In the present study, we carried out the seismic performance evaluation of two of the concrete dam with different shape, for explaining the relationship of the dam of the shape and seismic safety.

This study results the shear capacity of a wall depending on the postion and reinforcement of the equipment opening using finite element analysis. Analysis results show that when the openings are placed in the corner, the shear capacity was reduced than in the center. and reinforcing with a steel sleeve can compensate for the reduced strength

Condition evaluation consists of visual inspection and durability assessment. Visual inspection has weakness such as subjectivity of inspector and qualitative evaluation. So, this study is fundamental research for realtime safety evaluation of landing pier based on safety inspection manual. This study is for safety assessment of pile safety and bearing capacity using realtime occurrence strain of pile.

In this study, quartile control chart method is tried to apply to determine limit values of existing dams of K-water’s instrumentation data for dam safety, show asymmetric distributed data, and the example of application is presented. The determined limit values of concrete stress meter and concrete non-stress meter by Shewhart method and quartile method show that the determined limit values by Shewhart method indicate that the majority of instrumentation are on abnormal condition, although the measured values are normal behavior. But, in case of the result of quartile method has such an error. Like this, it is judged that the determination of the limit values of dam instrumentation, show asymmetric and abnormal distributed data, by the quartile method is appropriate. Therefor The quartile method is applied to the determination of limit values of existing dam instrumentation of K-water.

본 연구는 지진이 발생할 경우 장대레일교량에 있어 레일과 상판 간의 종방향 상호작용에 미치는 영향을 검토하기 위한 것으로, 해 석모델에 여러 하중조합과 함께 지진하중을 적용함으로써 대상 철도교량 레일에서의 축방향 부가응력과 레일-상판 간 상대변위의 변화를 산 출하였다. 해석 결과, 본 연구 대상 철도교량의 경우 철도시설공단에서 제시하고 있는 표준응답스펙트럼을 적용할 때 레일부가응력은 대부분 의 하중조합에 대해 허용기준 내의 값을 보이고 있는 반면, 레일-상판 상대변위는 공단에서 제시하는 허용기준을 초과하고 있는 것으로 나타났 다. 따라서 레일-상판 상대변위가 레일부가응력에 비해 상대적으로 더 허용기준을 만족시키기 어렵다는 것을 알 수 있었으며, 아울러 고베 대 지진과 같은 큰 규모의 지진이 발생하면 레일부가응력과 레일-상판 상대변위는 허용기준을 충족시키지 못하므로 이에 대한 적절한 내진 대비 가 필요하다.

In order to evaluate the seismic safety of weir structure subjected to seismic ground motions, Non-linear elastic 2D plane strain Finite Model (FE) was developed in ABAQUS. Also, the 1994 Northridge earthquake as a ground motion uncertainty was selected. The numerical results show that the tensile stress was increased with increase the friction coefficient

TLP (Tension Leg Platform) is the marine structure for the buckling evaluated to ensure the safety. ABAQUS program was conducted the buckling of TLP. A global model which simulated entire TLP structure has too many elements. This leads a large consumption of time and the hardware for analysis. Therefore, dividing the global model into the detailed models and the local models are significant. In this study, the buckling strength evaluation of the TLP structure members was proceed via non linear finite element analysis presented in DNV-RP-C208.