• Korean Chemical Engineering Research
• /
• v.60 no.4
• /
• pp.512-518
• /
• 2022

In this study, safety devices for ammonia tanks of a company in Ulsan petrochemical industrial complex were studied. The type of a tank is cylindrical and this tank was originally designed to store propylene in 1972. Due to the changes of the production schedule according to market environments, the usage of this tank has been changed to store ammonia. Despite of the changes of materials, there is no scientific information or reviews for guaranteeing the safety. Therefore, in this study, the current status of this tank is investigated to confirm that the operational conditions are complying with safety conditions. Moreover, the safety devices such as an ammonia absorbing system and water curtains are analyzed how they mitigate the impact of an accident. In addition, consequence analysis is performed to provide a proper emergency response plan. Throughout these analysis, it is confirmed that installed safety devices effectively mitigate the impact of accidents, and the necessary time for an emergency response plan is suggested when ammonia release.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.35 no.1
• /
• pp.31-38
• /
• 2015

In this paper, change of load carrying capacity of bridges with time was analyzed referring to the safety inspect data stored in the KISTEC. From this study, it was known that the capacity is rated differently by various parameters such as inspector's subjective. Accordingly, an improved method, in this paper, is suggested which can correct deviation due to several uncertainties involved in rating process. The suggested method can be utilized for efficient maintenance of bridges such as cycles and determination of priority of retrofit, and estimation of service life etc.

• Journal of the Korean Institute of Gas
• /
• v.7 no.2 s.19
• /
• pp.42-47
• /
• 2003

To prevent major accident from toxic gas release, explosion, or fire in chemical processes, it needs dynamic control of human error with mechanical failure. Although most of major accidents occur with a coupling of human error and mechanical failure, numbers of researches have studied human error and mechanical reliability independently, but no where cross each other, to reduce the risk in the process. This work focuses on the coincidence of human error and mechanical failure for management of human error, and on some important performance shaping factors to propose a method for improving safety effectively of the process industries.

• The Journal of Engineering Geology
• /
• v.33 no.4
• /
• pp.725-736
• /
• 2023

The compliance of deep geological disposal facilities for high-level radioactive waste with safety objectives requires consideration of uncertainties owing to temporal changes in the disposal system. A comprehensive review and analysis of the characteristics of this evolution should be undertaken to identify the effects on multiple barriers and the biosphere. We analyzed the evolution of the buffer, backfill, plug, and closure regions during the early phase of the post-closure period as part of a long-term performance assessment for an operating license application for a deep geological repository in Finland. Degradation mechanisms generally expected in engineered barriers were considered, and long-term evolution features were examined for use in performance assessments. The importance of evolution features was classified into six categories based on the design of the Finnish case. Results are expected to be useful as a technical basis for performance and safety assessment in developing the Korean deep geological disposal system for high-level radioactive waste. However, for a more detailed review and evaluation of each feature, it is necessary to obtain data for the final disposal site and facility-specific design, and to assess its impact in advance.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.12
• /
• pp.468-474
• /
• 2019

Korea had the highest accident rate among OECD countries in 2018, with 8.4 per 100,000 population, ranking 4th among 35 countries. In addition, the accident rate of traffic with children and the elderly was also high. This study reviewed the relevant literature and analyzed the traffic-accident analysis system. Customized traffic safety facilities were developed. In addition, by measuring the visibility of the traffic safety facilities by installing a test bed, this study measured the forward driving frequency and vehicle driving speed while driving. As a result of applying the "pedestrian pedestrian model" collision test model, the possibility of serious injury after installing the facility was reduced greatly to 4.6%. In this study, the visibility of traffic safety facilities and the effect of reducing the traffic speed were verified through test beds. Recognizing traffic safety facilities will reduce traffic accidents.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2008.10a
• /
• pp.296-296
• /
• 2008

국내 절토비탈면은 이상 기후 및 건설공사의 증대로 인해 증가하고 있는 추세이며 장마철 및 태풍으로 인해 비탈면의 붕괴로 많은 인명 및 재산피해가 발생되고 있는 실정이다. 국내에서 사용되고 있는 기존의 비탈면의 설계기준은 암반의 불연속면에 대한 조사를 실시하고는 있지만 주로 암반의 굴착난이도를 토층, 리핑암, 발파암으로 구분하여 각각의 비탈면 절취경사를 결정하여 사용하는 방법을 사용하였으며 이러한 기준은 단순히 암석의 강도를 기준으로 설정되어 있으므로 암석의 공학적 특성 즉, 암반내 불연속면 방향성, 연속성, 충진물질, 마찰각, 풍화속도 등의 영향으로 공용후 비탈면 구배의 재조정 및 보강이 빈번하다. 국내외 절토비탈면의 설계기준은 각 기관별로 산재되어 있었으며 비탈면에 대한 설계 및 시공 등에 관한 기준은 도로와 철도 설계기준에 일부 반영되어 있을 뿐 항만, 댐, 택지조성 등 기타 시설 설계기준에는 비탈면에 대한 기준이 마련되어 있지 않아 표준적인 비탈면 설계기준 및 유지관리지침이 등이 필요하였다. 이러한 문제점을 보완하기 위해 2004년부터 2006까지 한국시설안전공단, 한국도로공사, 대한주택공사가 협동으로 연구한 건설공사 비탈면 설계 시공 및 유지관리에 관한 연구의 결과로 2006년도에 "건설공사 비탈면 설계기준"이 수립되었다. 이 설계기준은 건설공사에서의 기존 상이한 기준들을 정리하고 동일화하는 작업을 수행하였으며 지반의 조사에서부터 대책공까지를 막나하여 정리하였다. 그러나 최근에 급격한 기후변화로 인한 비탈면붕괴 빈번함에 따라 과거 적용되어 왔던 이들 기준을 적용하는 경우, 특히 상부 토층 및 풍화암 구간에서 많은 설계안전율을 만족하지 못해 많은 보강을 수반해야 하는 문제가 발생되고 있어 그 원인에 대한 분석을 수행하고자 하였다. 2006년도 정리된 기준은 과거에 적용하여 온 유기시의 안전율 조건을 Fs > 1.1~1.2을 적용하였던 것을 Fs > 1.2로 통일하였으며 지하수위 조건은 지표면에 위치하도록 하였다. 지하수위 조건은 풍화암 및 토층의 경우, 과거 지표면에 -3m를 적용한 시기가 있었으나 지표면에 지하수위를 적용하는 것이 일반적인 해석방법이다. 이러한 결과의 원인을 검토해 보면 다음과 같다. 첫째, 풍화암 및 토층에 적용되어 온 지반강도 정수가 과거 적용한 값보다 최근에는 작아지는 경향을 보이고 있다. 둘째, 지하수위 적용문제로 현재 지표면에 지하수위를 두어 안전율을 감소시키는 문제로 이는 최근 들어 많은 연구기관에서 강우시 간극수압의 증가에 대한 연구가 활발하게 진행되고 있다. 그러나 침투수 해석은 현행 기준에도 강우의 침투를 고려한 해석을 실시하는 경우 FS > 1.3 적용하는 것으로 되어 있으나 대부분의 해석에서는 적용이 되지 못하고 있는 실정이다. 셋째, 안전율이 과거에 주로 적용된 Fs > 1.1에서 Fs > 1.2로 상향 조정되어 우기시의 설계안전율 만족시키지 못하는 문제이다. 그러므로 이러한 문제점을 개선하기 위한 검토가 필요하며 장기적으로 이에 대한 합리적인 기준을 개정하는 작업이 추후에 수행되어야 할 것으로 판단된다.

• 한국노년학
• /
• v.30 no.3
• /
• pp.843-853
• /
• 2010

The purpose of this study is to find out the characteristics of elderly pedestrian accidents and to suggest policy implications to enhance the level of elderly pedestrian safety. Although much efforts has made to enhance traffic safety environment, pedestrian traffic accidents among elderly population are not significantly decreased. This is mainly because current traffic safety measures do not much consider the characteristics of elderly pedestrians in the aspects of physical and psychological conditions. Main findings from vehicle-pedestrian traffic accident data and survey are as follows. First elderly pedestrians have high probability of traffic accident near crosswalks or cross streets rather than on crosswalk or cross streets. Second they need more green light time for crossing the streets. Third, they feel motor cycles running on the side walk and parked vehicles on the side walk are the most dangerous factors. Forth, general drivers do not have reasonable understanding for the walking behaviors of elderly pedestrians. Fifth, elderly pedestrians frequently need to rest while walking. Sixth, elderly people do not see clearly or understand traffic signs. Finally, many elderly pedestrians experience accidents or inconvenience while walking on the sidewalk.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.21 no.1
• /
• pp.79-92
• /
• 2019

In this paper, we propose a method to determine whether to install the accommodation facility of the multi-utility tunnel more effectively in the basic planning phase, and to set up an evaluation system to determine the configuration and kind of accommodation facility. For the configuration of the accommodation facility, 98 alternatives were analyzed for 7 accommodation facility. For the evaluation system of the accommodation facility, index related to feasibility and economic in basic planning phase were selected. The evaluation system classified as spatial, effective, and cost evaluation was presented reflecting the selected index, and AHP analysis was performed for weight setting. The results of this study will be helpful for users including designers to shorten the time and increase the efficiency in the process of determining accommodation facility of the multi-utility tunnel in basic planning phase.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.25 no.5
• /
• pp.102-113
• /
• 2021

The deterioration environments caused by de-icing salt and airborne chlorides in the seashore, evaluated in the "Detailed guideline for safety and management practice of facilities (performance evaluation)", were reviewed in terms of penetrated chlorides into concrete on various road facilities. Target concrete structures, in this study, were 4 concrete barriers in Gangwon area, 3 concrete barriers and 1 retaining wall in Busan area, and 4 bridges in Gangwon-do, Seoul, Gyeonggi-do, and Busan. The deterioration environments were classified into three categories: direct and indirect de-icing salt attack, and airborne salt attack depending on the distance to seashore and the height of pier, and the penetrated chlorides in to concrete were analyzed. The results showed that (1) the regional deterioration environments were clearly classified by de-icing salt sprayed days (snowfall days), (2) the penetrated chlorides increased significantly when leakage occurred through slabs or expansion joints, and (3) the airborne chlorides affected to a height of 20 m concrete in the seashore, Busan. From these, it could be confirmed that the chloride ion penetration properties depend on the exposed aging environment, member location and height, and deterioration status, even on the same structure, so the selection of target members and location is very important in the inspection and maintenance. If the database of penetrated chlorides properties in various deterioration environments is constructed, it is expected that the proactive durability management on concrete structures will be possible in the field.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.23 no.4
• /
• pp.37-44
• /
• 2019

The purpose of this study is to rationally determine the priority of seismic reinforcement of main(key) members of bridges. Cable Supported bridge was selected as the evaluation target and the reliability based on the probability distribution was used to evaluate the seismic fragility of the key members as a quantitative indicator. The safety factor, which is a random variable, is considered an artificial (fixed load and live load) load and a natural (earthquake, wind, temperature, etc.) load. The seismic load is applied as a possible earthquake during the lifetime of the bridge. From analyzing the fragility of each key member based on the seismic reliability, it can be concluded that the shoe (23.8%) was the most fragile, where the other members are ranked as place concrete (20.5%), pier (18.9%), foundation (17.3%) and cable (5.0%) respectively.