• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.59-73
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• 2016

The demand for subsurface transport is increasing. The users and the operators of road tunnels are exposed to risks with different causes. One main cause, however, is the traffic situation in the event of accidents. The importance of a Quantified Risk Assessment is increasing to quantify the safety of road tunnels and to balance the requirements (capacity, reliability, availability, maintainability and safety) of various stakeholders. Although there are classical methods for risk assessments, such as ETA and FTA. These methods are used for relatively simple cases because it could not relevantly reflect the diversity and relationship of the parameters. Therefore, a quantitative risk assessment based on Bayesian Probabilistic Networks considering interdependence between the parameters of a complex underground system as a double deck tunnel is provided.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.139-140
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• 2022

This study aims to present basic data for fire risk assessment. In the existing fire risk assessment, the operation of fire safety facilities is not considered. In addition, there is a lack of data on the fire growth rate to predict the spread of fire. Therefore, this study intends to build a fire scenario using fire statistics data. In addition, the fire growth rate is to be derived in consideration of the floor area of burnout and the cause of fire.

• Journal of Korean Tunnelling and Underground Space Association
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• v.9 no.1
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• pp.63-74
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• 2007

Unexpected ground conditions have always been a major problem for the construction of tunnel. Therefore, it is necessary to evaluate the risk capacity before and/or during construction of new tunnel. This paper presents the simplified risk assessment system using modified stability number (N), namely Underground Risk Index (URI) system, to evaluate the tunnel risk possibility in the design stage. URI is a scoring system for risk possibility by rating the each appraisal elements. The modified stability number (N) which is one of risk factor in the Interaction Matrix parameters such as RQD, UCS, weathering, overburden, stability number, ground water-table, RMR, permeability and so on, is used in the system. In addition, the case study is performed in order to verify the applicability of URI-system in practice.

• Journal of Korean Tunnelling and Underground Space Association
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• v.10 no.1
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• pp.1-15
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• 2008

Recently, because of the various factors by uncertainty of underground, the risks in tunnelling have been occurred increasingly. Therefore, it is very important to estimate and control the risks considering geotechnical conditions for tunnel stability and environmental problems by tunnel construction. In this study, the risk analysis for tunnel stability was carried out by classifying the risk factors such as ground support capacity, ground settlement, the inflow of groundwater into the tunnel and the damage by the earthquake. Also, the risk assessment for the environmental problems was performed by calculating the vibration and noise by blasting and the drawdown of the groundwater level caused by tunnel construction. Each risk factor was evaluated quantitatively based on the probabilistic and statistic technique, then it was analyzed the distribution characteristic along overall tunnel site. Finally, it was evaluated that how much each risk factor influences on the construction cost with a period for tunnel construction, so it is possible to perform reasonable tunnel design which was capable of minimizing the risks in the tunnel construction.

• Journal of Environmental Impact Assessment
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• v.19 no.3
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• pp.271-279
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• 2010

We conducted a quantitative human health risk assessment with respect to inhalation of heavy metals for residents of housing developments in "new towns" where an incinerator will be operated within the area scheduled for construction thereof. To assess potential human health risk we calculated the amount of heavy metals emitted from the incinerator, and then forecasted the potential health impact on adjoining areas where new housing is to be developed (i.e. "new towns") at different altitudes by a using SCREEN-3 model. We assessed Cancer Risk (CR) caused by known carcinogens using the Inhalation Unit Risk criteria developed by the US Environmental Protection Agency. Notably, we assessed risk by determining concentrations of heavy metals on a floor by floor basis, as apartment buildings are to be constructed near the incinerator according to a pre-devised plan. Results indicated that cancer risk for most carcinogens exceeded US EPA standards for the highest locations at each collection point. This result indicates that construction of high buildings in areas adjoining incinerators is undesirable, and that measures to lower carcinogens are needed. The results of this study, which assessed health risk from exposure to heavy metals emitted from a nearby incinerator, can be useful in land use planning with respect to the location of housing developments in new towns, as well as the heights of any buildings constructed. Furthermore, the methodology deployed herein with respect to risk assessment can be helpful for policy makers and the general public in the event of conflicts regarding incinerator projects in the future. The results herein may also be of merit in determining priorities when establishing harm reduction measures for carcinogens at incinerators. However, the study does contain several limitations. The SCREEN-3 model, a kind of screening model that provides conservative results, can provide higher forecasted concentrations of air pollutants than other models. Moreover, although the incinerator in question is set to be a thermoselect type, domestic data for emissions from these incinerators is not available, and assumptions were based on a stoker type incinerator. Insufficient domestic data likewise compelled the use of data of USA, resulting in possible errors in results. Continued research will thus be required to develop systematic methodologies that address the foregoing factors and produce more reliable outcomes.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.931-946
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• 2018

In line with the increased usability of utility pipe conduits in urban areas, construction and R&D activities of utility tunnel, incorporated with the shield TBM method, are actively under way. The utility tunnels are installed through underground excavation, and thus are relatively weak in terms of construction safety. However, hazards associated with the utility tunnel construction have not been properly identified, despite the introduction of a policy to the 'Design for Safety' for the purpose of reducing accident rates in the construction industry. Therefore, in this study, following the derivation of hazards associated with utility tunnel, these hazards were then used as the basis to uncover key safety hazards requiring extensive management in a field, which were then used to conduct a risk assessment having applied the matrix method so that the results can be utilized in risk assessment during the stages of utility tunnel planning, design, and construction, while also serving as a data reference.

• Journal of the Society of Disaster Information
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• v.15 no.4
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• pp.493-501
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• 2019

Purpose: The purpose of this study is to prevent construction safety accidents, and the design safety systems were reviewed. This paper aims to establish as an effective system by looking at the implementation procedures and contents of the design safety review system. Method: We reviewed the purpose and content of the law, accident statistics, etc. for the study. In addition, we looked at the implementation plans for actual construction sites using the 'design safety' assessment process as defined by the Act. Results: We divided it into the data review phase, the risk factor elicitation and alternative setup phase, and the design safety assessment report preparation stage. Conclusion: it is necessary to derive risk factors that take into account the diversity of construction sites. However, the effectiveness of other reports is questioned as they are often copied and written. Therefore, it is necessary to strengthen external verification procedures attended by construction safety experts.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.204-205
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• 2015

Exterior insulation board in cast-in-place concrete form system could reduce construction period and improve quality in apartment construction. However, the method is progressed with insulation and concrete frame works at the same time, then risk is increased in duration control and quality management. Therefore, this paper analyzed risk factors through FMEA method. We found that the key risk factors delaying schedule was insulation material that soaked in the rain and quality defects on the insulation material joint. Based on this research, the risk management approach should be developed for improvement of method activation.

• Journal of the Korean Professional Engineers Association
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• v.34 no.5
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• pp.77-81
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• 2001

The industrial accident in subway of late is increasingly coming to the front as a serious problem of society because a scale of industrial accident is a large size, and powerfulness, while the percent of accident is decreasing as a result of industrial facilities with the largeness of equipment, automation, and high horse-powering. In this paper, a study on the estimation of accident loss prevention cost and risk analysis in subway construction is proposed as an alternative to the techniques currently used in the general construction projects safety. Then the concept of risk evaluation using a risk assessment model is presented to drive value of risk and numerical example for risk analysis. A means for this does grasp the importance of educational factor by way of analyzing the causes of accident through statistical data of labor department, emphasizing the necessity and the importance of safety education, being helpful to act safety by decreasing insecure activity which ranks the majority of accident causes with putting the education program, form, method into practice that are suitable for a place of business.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.99-100
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• 2022

As the danger of exposure to the asbestos has been revealed, the importance of demolition asbestos in existing buildings has been raised. Extensive body of study has been conducted to evaluate the risk of demolition asbestos, but there were confined types of variables caused by not reflecting categorical information and limitations in collecting quantitative information. Thus, this study aims to derive a model that predicts the risk in workplace of demolition asbestos by collecting categorical and continuous variables. For this purpose, categorical and continuous variables were collected from asbestos demolition reports, and the risk assessment score was set as the dependent variable. In this study, the influence of each variable was identified using logistic regression, and the risk prediction model methodologies were compared through decision tree regression and artificial neural network. As a result, a conditional risk prediction model was derived to evaluate the risk of demolition asbestos, and this model is expected to be used to ensure the safety of asbestos demolition workers.