• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.6
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• pp.47-52
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• 2008

Deicer has been generally used for prevention of a road freezing in winter, and the usage amount is increasing every year. However, deicer may induce the decrease of bond strength, surface scaling, and environmental pollution. In this study, the field test was performed to investigate the deterioration of concrete road structures used for 17 years. And, the corrosion resistance characteristics were compared for the existing deicer and eco-friendly deicer. According to the field test results, the penetration depth of limit chloride amount was about 40mm, and the average concentration of chloride was $3.45kg/m^3$ at the surface of structures. On the contrary, the carbonation depth was slight. The penetration depth of eco-friendly deicer was less than the existing deicer, and the corrosion resistance of eco-friendly deicer was higher.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.2 s.21
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• pp.37-44
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• 2006

Any vehicle and equipment whose total weight is more than 40ton and its axle weight is 10ton or above is banned to cross any bridge in our country under section 54 in the Highway law. This restriction results from the accumulation and application of safety factors about which there is type specification in the "standard design vehicle". And in "standard design vehicle", Vehicle load to bridge is assumed concentrating one. Based on this restriction, there is an issue that military tank which has a total weight of 51ton (63ton in case of the US tank) can not cross any bridge. However, many research and practical examples concerned manifest that it is possible for military tanks to cross these bridges. The reasons of this issue in the current Highway law's provisions are analyzed in this paper. Correspondingly, feasibility of military tanks passing these bridges are discussed here. At last, considering economical efficiency and practicability for military, several suggestions and improving measures are put forward. This research has certain reality significance to guide bridge design considering the passage of military heavy vehicles.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.1
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• pp.31-37
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• 2008

Traffic flow which is prescribed under previous traffic effect/access act is analyzed by traffic volume, V/C, mean speed on road and LOS on the intersection. These indexes based on analytical method can not consider stochastic characteristics of traffic flow. Moreover it is hard to analyze traffic flow visually in whole traffic effect area because only individual road and intersections are targeted. In this study, it is devised to show traffic flow analysis method within traffic effect area visually applying microscopic-simulation by car-following theory, and then based on this, effect analyze ways are studied according to space range plan, improvement measure establishment and etc. To execute this study, effect area is set up using V/C, and the change of traffic current around development area is analyzed using microscopic-simulation program.

• Journal of The Geomorphological Association of Korea
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• v.15 no.2
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• pp.25-35
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• 2008

Typhoon Ewiniar and Bilis followed by heavy rainfall in July 2006 triggered massive slope failures and debris flows along the Osaek valley within Seoraksan National Park. Since national road 44 is constructed along the fault-line, the susceptibility of hazard in the area is very high. Debris flows in Osaekcheon are mobilized from landslides near the ridgelines and peaks when heavy rainfall elevates pore pressure and adds weight to the hillslopes, causing failure. Stream flows falling onto the existing colluvium or channel-margin deposits also trigger debris flows. Steep slopes constructed along the road and thin regolith in the slope is the main reason for the landslide in the upper stream. In middle reaches of stream, under-fit drainage utilities and narrow bridges cause the overflow, this then triggers debris flow. Overflowing and erosion in the channel margin deposits is main reasons for the debris flow. The intensities and frequencies of heavy rainfall are certain to increase, so early warning and management system for the landslide-related hazard is urgently needed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.4D
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• pp.291-303
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• 2012

In order to lead safe driving, it is better to provide dynamic and detailed information on how the driver using the relevant road should behave as concerning movements of individual car rather than providing monotone and static information of reducing of speed to unspecified drivers. Assuming road and communication of highway where real-time collection and transfer of information on vehicles and road traffic status is possible, the purpose of this study was to provide real-time safe distance by considering road traffic condition such as road condition and driving condition, travel speed and distance between preceding/following vehicles. We intended to provide basic information about dangerous situation by defining different values of condition based column ($C_{condition}$) in accordance with the road surface condition, based on which Real-time Safety Distance Index(RSDI) is to be calculated comprehensively reflecting speed of preceding and following vehicles, distance between vehicles, vertical alignment and road surface condition on the scope of expression column ($C_n$). We intended to enable the driver to secure safety by providing the calculated Real-time Safety Distance Index (RSDI) so that the driver can intuitively sense and sufficiently cope with a dangerous situation where collision of vehicles may occur. The calculated RSDI value is comprised of 30 unit columns and will be provided to the driver being divided into risk evaluation grades of 3 predetermined steps, 'warning', 'dangerous' and 'normal'.

• International Journal of Highway Engineering
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• v.14 no.6
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• pp.103-110
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• 2012

PURPOSES : In Korea, over 70 percent of the land consists of mountainous and rolling area. Thus, tunnels continue its upward trend as road network are extended. In these circumstances, the importance of tunnel has been increased nowadays and then its safety investigation and research should be performed. This study is focus on confirming and improving the safety of tunnel. On tunnel hood, sunglare effect can irritate driver's behavior instantly and this can result in incident. METHODS : The study of this phenomenon is rarely conducted in domestic and foreign papers, so there is no proper measure for this. This study analyzes the driving environment of the effect of sunglare effect on tunnel hood. RESULTS : Traffic accidents stem from complex set of factors. This study build the Traffic Accident Prediction Models to find out the effect of sunglare effect on tunnel's hood. The independent variables are traffic volume, geometric design of road, length of tunnel and road side environment. Using these variables, this model estimates accident frequency on tunnel hood by Poisson regression model and Negative binomial regression model. Although Poisson regression model have more proper goodness of fit than Negative binomial regression model, Poisson regression model has overdipersion problem. So the Negative binomial regression model is used in this analysis. CONCLUSIONS : Consequently, the model shows that sunglare effect can play a role in driving safety on tunnel hood. As a result, the information of sunglare effect should be noticed ahead of tunnel hood so this can prevent drivers from being in hazard situation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.4
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• pp.438-444
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• 2019

With the increasing supply of vehicles, construction of new roads and expansion of existing roads are growing and this is leading to a proportional rise in diverse hazards on a road. These hazards are classified into fixed hazards and variable hazards. Currently, drivers receive information of fixed hazards, such as overspeed, frequent accidents, and rock fall through navigations. However, variable hazards are more hazardous than fixed hazards. Map companies frequently enter information of variable hazards manually, but it is less real-time and hard to deal with unforseen hazards. This paper is intended to implement a road hazard warning system for making a contribution to pubic interests by improving this problem and delivering real-time information of hazards to drivers, and suggest a direction for using information of hazards on a road.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.3
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• pp.19-26
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• 2009

In this study, flowable backfill made with weathered granite soil is tested to provide basic engineering properties that can be used as design input to overcome settlement problems in road pavement due to low stiffness of backfill which is generated by porosity of the soil. For design purpose, a proper mixing ratio is developed first. Then several test methods including FF/RC, PMT and LDWT including axial compression test are adapted for checking stiffness and measuring axial strength of the material separately that can be used for design values.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.6
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• pp.99-108
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• 2010

In this study, the characteristics of flow within and around a crossroad connected symmetrically with four roads are numerically analyzed by using a two-dimensional well-balanced HLLC finite volume model. As results of simulations and analyses, the numerical model employed in this study describes relatively well the complex water surface in a crossroad according to the conditions of inflow and road slope. Moreover, the predicted temporal and spatial variations of water depths in a crossroad and outflows at two downstream boundaries agree relatively well with laboratory measurements.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.83-90
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• 2010

The purpose of this study is to establish the standard of fire lane design to improve the performance of disaster prevention in local area. To accomplish it, we have focused on three research methods as below: first, we have expected disaster occurrence based on emergency tendency in local area; second, we have verified fire lane routes design through fire lane modeling and network analysis; third, we have quantitatively examined a possibility of danger of fire lanes through current road network modeling and analysis. The result of this study could be helpful to effective fire lane designs and quantitative analyses.