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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of Korean Society of Hazard Mitigation
Journal Basic Information
Journal DOI :
Korean Society of Hazard Mitigation
Editor in Chief :
Moo Jong Park
Volume & Issues
Volume 14, Issue 6 - Dec 2014
Volume 14, Issue 5 - Oct 2014
Volume 14, Issue 4 - Aug 2014
Volume 14, Issue 3 - Jun 2014
Volume 14, Issue 2 - Apr 2014
Volume 14, Issue 1 - Feb 2014
Selecting the target year
A Numerical Study on Securing Fire Safety of the Evacuation Space in Apartment Buildings
Ahn, Chan-Sol ; An, Jae-Hong ; Yeo, In-Hwan ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 1~7
DOI : 10.9798/KOSHAM.2014.14.4.1
This study is intended to carry out the numerical analysis of mockup fire test with regard to evacuation space in apartment building which is required by current domestic building code, and the data on temperature and radiant heat analyzed was compared with the actual test data. During such process, thermal current flow inside evacuation space and transferred through the window was monitored and the safety of the people at evacuation space was determined accordingly. Consequently, thermal energy transferred from non-thermal barrier fire door served to transfer convection heat to the air inside evacuation space, causing to form a flow momentum and the clockwise flow. As indicated in mockup test result, convection heat and radiant heat transferred from the heat source through non-thermal barrier fire door caused the thermal damage to the evacuates, endangering the fire safety.
Prediction of Effective Compressive Strength of Column-slab Joint Considering Slab Confinement Effect
Lee, Joo Ha ; Yoon, Young Soo ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 9~15
DOI : 10.9798/KOSHAM.2014.14.4.9
In this study, rational prediction models for the effective compressive strengths of high-strength concrete (HSC) interior columns with intervening normal strength concrete (NSC) slabs are developed. A structural analogy between HSC column-NSC slab joint and brick masonry is used to develop the prediction models. In addition, the aspect ratio of slab thickness to column dimension and the surrounding slab confinement effect are considered in the models. The proposed prediction model is verified by comparison with experimental results and various prediction expressions. As a result, the proposed equation provided superior predictions over all of the existing effective strength prediction approaches including KCI structural concrete design code (2012).
Performance Evaluation of Y Type Plate Connection between Cft Column and H Shape Steel Beam for Top-down Method
Jung, Hyung-Suk ; Choi, Chang-Sik ; Choi, Hyun-Ki ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 17~23
DOI : 10.9798/KOSHAM.2014.14.4.17
Recently, problems of adjacent buildings settlement, dust and noise arose from dense urban construction work. In order to solve this problem, a variety of Top-down method was used in urban construction work. In this study, new Top-down method was developed to improve the performance of urban construction and new detail of CFT column - H shape steel beam connection with Y type plate was proposed. The performance evaluation was performed with the proposed detail. Four specimens was made with introduction of structural diaphragm design concept. Test was performed to evaluate the parameter of Y type plate and to confirm the safety of proposed detail. Also, the test result of proposed detail was classified by performance evaluation criteria of connection in Eurocode3.
Development and Performance Evaluation of ㅍ-Section Steel Column New Shape Weak-Axis Connection
Kim, Sung Bae ; Cho, Han Sol ; Lee, Tae Gyu ; Kim, Sang Seup ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 25~32
DOI : 10.9798/KOSHAM.2014.14.4.25
The importance of composite structure systems such as CFT in the building structure is being highlighted which led high-rise buildings, enlarged and long spanning. CFT is difficult to apply to the field due to the installation of the internal and external diaphragm. Therefore, this study developed concrete filled ㅍ-section column structure systems to solve the problem in accordance with conventional systems for CFT and evaluated structural performance of ㅍ-section steel column New shape weak-axis connection. Five specimens are built to test variables that thickness of welding plates and monotonic loading tests are performed. As the result, new shape weak-axis connection can adjust the strength and rigidity according to welding plate thickness.
Investigation of Lateral-Torsional Buckling Strength Trends in Monosymmetric Stepped I-Beams Subjected to Several Loading Conditions
Surla, Albert S. ; Park, Jong Sup ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 33~41
DOI : 10.9798/KOSHAM.2014.14.4.33
It has been proven in recent studies that for monosymmetric I-section beams, in considering bending moment diagrams caused by any combination of applied end moments and transverse loads acting at the shear centre, the lowest critical lateral torsional buckling moment does not necessarily correspond to uniform bending. This finding is different from the intuitive expectation that researchers have that for lateral torsional buckling of thin walled beams, the lowest critical lateral torsional buckling moment always corresponds to a uniform bending moment diagram. To determine the applicability of the findings stated, considering stepped beams, this study will be focusing on the comparison of the lateral torsional buckling strength trends in monosymmetric I-beams having doubly stepped and compact cross section. Several loading conditions will be applied to see the effect of different moment diagrams having different inflection points on the lateral torsional buckling strength of stepped beams. The study will be made using the finite element program, ABAQUS. The study will investigate stepped beams having monosymmetric ratios ranging from 0.5 to 0.9. These ratios correspond to varying bottom flange width while keeping the top flange width unchanged. Unbraced length to height ratio of the beam to be analyzed is 20. Finally, the findings for this study will be shown using illustrative figures and conclusions will be made.
An Adaptive Mesh Generation Scheme for the Finite Element Method
Yoon, Chongyul ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 43~49
DOI : 10.9798/KOSHAM.2014.14.4.43
Ideal structures in hazard mitigation systems must have automated state identification capabilities in order to function acceptably in case of a severe hazard. This capability must be efficient in terms of real time computations. The finite element method has become the most widely used method of structural analysis and in an automated finite element structural analysis, an adaptive mesh generation scheme has become an essential component. Without an adaptive scheme, the same mesh is used throughout the analysis and this causes computational inefficiency due to fine mesh where they are not needed and inaccuracy due to overly distorted elements formed during the analysis that may proceed undetected as only the initial and the final element shapes are generally checked in practice. This is especially true for dynamic and nonlinear problems in structural analyses. Thus, the finite element mesh for these types of analyses must be dynamically adaptive and computationally efficient. In this paper, an efficient adaptive finite element mesh generation scheme for dynamic analyses of planar problems is described. Representative strain values are used for error estimates and refinements of meshes use combinations of the h-method (node movement) and the r-method (element division) based on a dispersion parameter. A coefficient that depends on the shape of element is used to correct overly distorted elements. A case study shows the validity and computational efficiency of the scheme. The study also demonstrates the potential applicability of the scheme`s effective use in complex structural problems such as those under severe environmental hazards such as seismic loads, erratic wind loads, and general nonlinear problems.
A Flexural Bonding Characteristic of GFRP Rebar Embedded in Concrete Beam Under Cyclic Loading
Oh, Hongseob ; Kang, Tae-Sung ; Oh, Kwang-Chin ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 51~57
DOI : 10.9798/KOSHAM.2014.14.4.51
A cumulative damage theory, which can model the effects of the magnitude and sequence of variable amplitude fatigue loadings, was examined. The concrete beam reinforced with GFRP Rebar specimens was prepared and tested in four-point flexural loading conditions. The variable-amplitude fatigue loadings in two and three stages are considered. The present experimental study indicates that the fatigue failure of concrete is greatly influenced by the magnitude and sequence of applied, variable-amplitude fatigue loading. The sum of the cumulative damage is found to be greater then 1.0 when the magnitude of fatigue loading is gradually increased and less than 1 when the magnitude of fatigue loading is gradually decreased. It is seen that the linear damage theory proposed by Palmagren and Miner is not directly applicable to the concrete reinforced with GFRP Rebar under such loading cases. The proposed nonlinear damage theory, which includes the effects of the magnitude and sequence of applied fatigue loadings, allows more realistic fatigue analysis of concrete structures.
Damage Rate of Reinforced Concrete Submerged Floating Tunnels Under Fire Scenarios
Seo, JiHye ; Han, Taek Hee ; Park, Woo-Sun ; Han, Sang-Hun ; Won, Deok Hee ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 59~65
DOI : 10.9798/KOSHAM.2014.14.4.59
Fire resistance performance of the SFT (Submerged Floating Tunnel) is important one of the various researches. If fire break out in SFT, it is damaged by thermal loads. The damage of the SFT varies by type of fire. Structure of the SFT is able to collapse partially by fire scale and fire exposure time. For this reason, fire resistance design of the SFT must be suggested. Fire resistance performance of SFT could be investigating for fire resistance design of SFT. Fire condition could be expressed fire curves which are suggested by fire scale and fire exposure time. In this paper, temperature distributions of the SFT were investigated through FE analysis under various fire scenarios. Heat transfer analysis was applied to investigate conduction of heat by fire. And there was to draw the biggest influence fire condition to the SFT from FE analysis results. Also, preliminary study was performed for fire resistance design.
Application of Radar Rainfall Estimates Using the Local Gauge Correction Method to Hydrologic Model
Lee, Jae-Kyoung ; Kim, Ji-Hyeon ; Park, Jong-Seo ; Kim, Kwang-Ho ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 67~78
DOI : 10.9798/KOSHAM.2014.14.4.67
The Radar-AWS Rainrate (RAR) calculation system operated by Korea Meteorological Administration has several limitations in estimating the rainfall amounts accurately, though the RAR calculation system estimates rainrate from real-time estimation of the Z-R relation using the reflectivity from weather radar and observed rainrate from Automatic Weather Station (AWS). This study applied the Local Gauge Correction (LGC) method which enables correcting the rainfall events occurred locally using the RAR calculation system and verified the accuracy of the LGC results. As a result, in the case analysis of the summer season (from June 2012 to August 2012), RMSE and correlation coefficient of the RAR calculation system are 6.39 and 0.87 and RMSE and correlation coefficient are 2.45 and 0.85, respectively, in the winter season (from December 2012 to February 2013). Therefore, the RAR calculation system has the accuracy of rainrate estimation. In this study, after the LGC method is applied to the RAR system, the accuracy of the RAR is improved in both summer (from 8.68 to 8.01 in RMSE) and winter seasons (from 2.58 to 2.00). The LGC method has also improved about 3 % than the Gauge to Radar (G/R) ratio. Furthermore, the corrected rainfall using the LGC method was inputted to the HEC-HMS to examine the accuracy of flood simulation. According to the results, the accuracy of flood results with the LGC method was improved 11.57% (in RMSE), 2.11% (in correlation coefficient), and 14.47% (Nash-Sutcliffe Efficiency) on average, along with the accuracy of hydrograph with the LGC method. Therefore, after the application of the LGC method, the RAR calculation system has sufficient capability to simulate the accurate rainrate while the LGC method can correct the amounts of rainrate from the RAR calculation system. It is advised that the corrected rainfall with the LGC method be utilized in hydrology field to produce more accurate hydrologic variables.
Comparison of VPR (Vertical Profile of Reflectivity) Models to Identify the Range Dependent Error in Radar Reflectivity
Yoon, Jungsoo ; Yoo, Chulsang ; Choi, Jeongho ; Ku, Jungmo ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 79~92
DOI : 10.9798/KOSHAM.2014.14.4.79
Due to the earth`s curvature effect, the height of the radar beam increases as the distance from the radar increases. So the radar rainfall shows the difference from the ground rainfall. The earth curvature is an important source of error among others, which is defined as the range dependent error. This study applied three VPR (Vertical Profile of Reflectivity) models to identify the range dependent error. The range dependent error were calculated by the difference between the 1.5 km CAPPI reflectivity and the reflectivity at 1.5 km estimated from the VPR, which were quantified separately by the bias and the root mean square error. This study evaluated what model can properly present the range dependent error. Model 1 referred to Fabry (1997) considering the bright band. Model 2 is the same as Fabry (1997) but with the uniform vertical profile below the bright band. Model 3, similar to model 2, has the exponential decreased pattern. Also, two different parameter estimation methods were considered: method 1 is to consider the reflectivity below the bright band and method 2 both below and upper the region. As an application result, the model 3 was found to be the most suitable for identifying the range dependent error.
Parameter Estimation of the Mixture Normal Distribution for Hydro-Meteorological Variables using Meta-Heuristic Maximum Likelihood
Shin, Ju-Young ; Lee, Taesam ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 93~99
DOI : 10.9798/KOSHAM.2014.14.4.93
Mixture distribution has been widely used in the water resources field since it can fit the statistical characteristics that a conventional unimodal distribution cannot. Furthermore, climate change often brings different behaviors that has never been happened before. Therefore, mixture distribution must be a good alternative in order to circumvent this change in frequency analysis. However, estimating the parameters of mixture distribution models is not an easy task and the expectation maximization (EM) algorithm has been widely used to estimate parameters of the mixture distribution. EM algorithm contains a number of drawbacks. In the current study, the drawbacks of EM algorithm are clearly illustrated and in addition, we proposed a new parameter estimation approach for the mixture normal distribution. To verify the performance of the developed model, simulation experiments were carried out. From the results of experiments, we concluded that the proposed model estimates the parameters more reliably than the EM algorithm. EM algorithm was not able to estimate the parameters in case of small number of data while the proposed method can.
Estimation of Snowfall Frequency and Selection of Appropriate Probability Distribution in Korea
Yu, Insang ; Kim, Hayong ; Chung, Gunhui ; Jeong, Sangman ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 101~109
DOI : 10.9798/KOSHAM.2014.14.4.101
In this study, snowfall frequency analysis was performed to determine the best fit distribution applicable for Korean in order to make a snowfall frequency map. The available 66 stations having a snowfall over 20 years were selected and the annual maximum snowfall were collected. Generalized Extreme Value, Gumbel, Weibull, 2-Parameter Gamma, 3-Parameter Gamma and Log-Pearson Type III distribution which are useful to extreme value frequency analysis were applied to determine appropriate distribution for Korea. The Method of Moment and the Probability Weighted Moment Method were applied as parameters of the distributions. The results show that Weibull distribution by Probability Weighted Moment Method is the best fit for snowfall frequency analysis. Mapping snowfall frequency were accomplished using snowfall frequency according to the available 66 stations through Kriging method by ArcGIS. Snowfall frequency map is expected to be useful in the design of building structures against heavy snow loading throughout Korea most especially in ungauged areas.
Stability of Temporary Bridge Bearing Method Passing Underneath Existing Subway Structure
Kim, Jin-Pal ; Park, Yang-Hoo ; Park, Seung-Hwan ; Cho, Kook-Hwan ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 111~118
DOI : 10.9798/KOSHAM.2014.14.4.111
930 Subway station in Seoul Subway line #9 is under construction underpassing Seoul Subway line #2 which is the only circulation in Seoul Metropolitan. This study verified the application of the temporary bridge bearing method which is used to station construction under existing Subway line #2 of Subway line #9 construction. Temporary bridge bearing method was conducted using an numerical analysis calculated FEM program MIDAS CIVIL of the verified proposed Method by monitored through heavy instrumentation system during construction. The upward movement from removing loads on structure is usually not considered in design. The upward movement is not an important factor for the stability of structure due to the small amounts of movement. However, it is not ignoreable for the safety of railway operation, since the upward movement of rail is considered to be one of the most dangerous factors for safety in railway. Therefore, the upward movement characteristic should be considered for railway projects. The proposed method can be used for similar project with stability confidence and cost savings through the verification procedure from this research.
Study of Relation between Elastic Wave Velocity and Electrical Resistivity in Saturated Medium
Lee, Jong-Sub ; Kim, Youngseok ; Hong, Seungseo ; Yoon, Hyung-Koo ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 119~126
DOI : 10.9798/KOSHAM.2014.14.4.119
The geophysical methods including elastic wave velocity and electrical resistivity have been widely used to obtain the geotechnical properties. The objective of this study suggests the relationship between elastic wave velocity and electrical resistivity because the two parameters are function of void ratio. The theory of Gassmann and Archie`s equation are applied for deducing the relation between geophysical methods and void ratio. The Field Velocity Resistivity Probe (FVRP) is used to obtain the elastic wave velocity and electrical resistivity in field which is southern part of Korea Peninsular. The data gathering is performed in the depth of 6.5~20.1 m at every 10 cm for obtaining various data and investigating the subsurface characterization in detail. For verifying the suggested equation, the measured data applied. The deduced compressional wave velocity shows a similar value with the measured compressional wave velocity. This study suggests that the proposed equation may be widely applied to estimate the reliability of measured values based on the geophysical method.
A Bearing Capacity Analysis of Micropile with Expanded Drill Hole
Lee, Jae-Min ; Kim, Doo-Hwan ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 127~133
DOI : 10.9798/KOSHAM.2014.14.4.127
The load-carrying capacity of a conventional micropile is determined by the adhesion between the rolled screw thread and the grout, and the skin friction force between the grout and the ground. One of the disadvantage of the conventional micropiles is that the boring depth can be deeper because of low load-carrying capacity and the brittle failure behavior between rolled screw thread and grout. Therefore, it is necessary to develop an advanced feature of a micropile system which efficiently increases load-carrying capacity with a reasonable cost. This study proposes an advanced type of a micropile system. The proposed micropile system consists of perfobond ribs installed steel rod to improve shear capacity between the thread and the grout, and partially expanded drill holes to increase resistance capacity between the grout and the ground. Through on-site pullout tests, it was found that load-carrying capacity increased significantly in the proposed micropile system, due to the shear keys created by the partially expanded drill hole. The proposed micropile system was also evaluated to be much more economical in a case study.
The Study of the Diagnosis on the Pavement Condition Using the Light FWD Equipment
Choi, Jun-Seong ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 135~141
DOI : 10.9798/KOSHAM.2014.14.4.135
For the faster and economical operation, this study is to propose the Light Falling Weight Test (LFWD) as the in-situ evaluation test of the pavement condition. the application case study is verified from in-situ field tests. LFWD instead of using the degree of compaction and plate bearing test is examined to pavement unbound layer condition and total pavement condition evaluation based on the in-situ elastic modulus and deflection. It is found that LFWD application is candidated from the large cylinder lab test and comparison test with dynamic plate load test. Condition analyses for the various pavement types are different using the deflections and in-situ elastic modulus. Evaluation process of the pavement condition using the Light FWD Equipment is proposed and validated from case application studies.
Evaluation of a Stream Gauge Network Using Multiobjective Optimization Method
Lee, JiHo ; Joo, HongJun ; Kim, HungSoo ; Jun, HwanDon ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 143~153
DOI : 10.9798/KOSHAM.2014.14.4.143
This study has evaluated the stream gauge network which is considered the total hydrological information and the importance class of stream gauge stations, and is applied to Namgang Dam basin. The total hydrological information and the importance class of stream gauge stations are two different physical parameters. We adopt the Euclidean distance method to consider them simultaneously. An equation obtained by the Euclidean distance method is used as the objective function in multiobjective optimization method to determine the optimal combination of the stream gauge stations for satisfying the both criteria: the maximum total amount of the hydrological information and the importance class of stream gauge stations. To evaluate the optimal stream gauge network, the representative unit hydrograph which is derived by real rainfall-runoff analysis is transferred into probability density function for the application of entropy theory concept. The importance class of stream gauge stations is determined by referring the result of MLIT (2010). As result of applying to Namgang Dam basin, The optimal stream gauge network obtained by the suggested method shows more satisfied the importance of stream gauge station purpose than the optimal stream gauge network obtain by the entropy theory only. This result implies that the optimal steam gauge network by the suggested method can consider both the total hydrological information and the importance class of stream gauge station. It is found that Namgang Dam basin needs at least 8 steam gauge stations among 12 steam gauge stations.
A Study on Building Public Broadcast System for Disaster
Oh, Kuk Ryul ; Lee, Chang Hee ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 155~161
DOI : 10.9798/KOSHAM.2014.14.4.155
Disasters are getting more unpredictable and more massive. However, technical methods such as disaster analysis do not help prevent and reduce disaster as much as expected. Disaster broadcast plays an important role in protecting property and reducing damage by spreading information about disasters. It can raise disaster awareness and educate people to evacuate and be prepared as well. Digitalized environment of broadcasting system is expected to support disaster broadcast service with new technology and contents. Considering the current situation, this study aims to propose measures and strategies required to build public broadcast system for disaster by case study of domestic and international disaster broadcast system.
Efficiency Analysis of Natural Disaster Damage Investigation System using Smartphones
Cho, Jaewoong ; Choi, Woongjung ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 163~170
DOI : 10.9798/KOSHAM.2014.14.4.163
Current natural disaster investigation has following procedures. First, handwrite the contents of damaged part of environment in the filed book while you are in the field. Then, attain field information like the photographs of damaged field, location map of the filed, and sectional view of the field. Lastly, go to the office with all the information, and organize investigated information of the field to input the information in the NDMS(National Disaster Management System) which formulate electronic disaster report. However, these kind of investigating disaster procedures has its weak points such as deficiency of time and labor when disaster breaks out because its works are overlapped between field work and office work. In order to get rid of these problems we need to develop following system: quick investigation of disaster skills, in accordance with system of automatical formulation of the electric disaster report of NDMS. In this study, we analyzed efficiency of natural disaster damage investigation system using smartphone through trial application to damaged area. The system can be quickly damage investigation by input details damage, shoot photographs, draw cross-section, input location map using smartphone in field. As a result, we found that it has more than 67% of time cut as we used it on the field.
A Plan on Measurement of the Damage Scale using Gyro Sensor in Smartphones
Cho, Jaewoong ; Choi, Woojung ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 171~177
DOI : 10.9798/KOSHAM.2014.14.4.171
In Korea, disaster investigation needs rapid and accurate because we must finish that during 7 days. But estimated damage amount for restoration is apt to be influenced by investigator`s subjective judgment because it is still manually calculated in the majority of cases. This makes accurate investigation for damage assessment difficult. Accordingly, National Disaster Management Institute has developed `Field Investigation System using Stereo Images` for quantitative measurement of disaster damage in 2009. And also, they has developed `Disaster Damage Investigation System using Smartphones` for prompt disaster damage investigation from 2011 to 2013. However, this two systems have different pros and cons. The Field Investigation System using Stereo Images is possible to be quantitative measurement of disaster damage, but the system is impossible to be prompt disaster damage investigation. On the contrary to this, another system that is using Smartphones is possible to be prompt disaster damage investigation, but the system is impossible to be quantitative measurement of disaster damage. In this study, suggest method on measurement of the damage scale using gyroscope in smartphone.
The Building and Effect Analysis of Natural Disaster Relief Goods Automated System
Seo, Jung Pyo ; Cho, Won Cheol ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 179~187
DOI : 10.9798/KOSHAM.2014.14.4.179
In Korea, natural disasters such as typhoons and floods occur frequently each year. Recently, however, due to climate change and other factors, the scale of damages from such natural disasters started to steadily increase. Our country existing relief goods management and distribution system, information is collected on the spot and then inputted into the National Disaster Management System (NDMS). Thus, the onsite work is duplicated in the office. Moreover, it takes much time to put the field information in order and the relief goods are managed manually, so the information cannot be shared in real time, which results in problems such as delays and duplicate payment of relief goods. To solve these problems, this research proposes the establishment of an information system for efficient management of relief goods based on U-IT. A mobile-based automated relief goods management system in which relief goods can be managed using a smartphone and Radio Frequency Identification (RFID) technology was developed, and the effectiveness of the system was analyzed. The analysis showed that the developed system is expected to effectively reduce Korea`s budget for relief administration by 950 million won a year.
Disaster Consequence Analysis on Blackout considering Interdependency Matrix and Resilience in Critical Infrastructure
Shin, Jin Dong ; Yoon, Kyung Ho ; Choi, Dong Sik ; Kim, Hyun Ju ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 189~198
DOI : 10.9798/KOSHAM.2014.14.4.189
Critical Infrastructure (CI) needs individual unit management and interdependency-based management because of their importance. So each CI is exquisitely and systematically managed under the related laws and regulations in terms of individual unit. But it is deficient to manage CI on the basis of Interdependency. Although "Disaster and Safety Management Fundamental Act" requires that CI is designated and managed in the light of cascade effect, coordinated response and individual unit, CI is primarily evaluated and protection plan is drawn-up by individual unit up to now. Thus this research suggested connectivity analysis methodology and drew up interdependency matrix through overseas case study. Furthermore this research analyzed disaster consequence on the basis of CI interdependency with consideration for blackout case and found out that interdependency matrix is useful to analyze relation among CI.
3D Numerical Analysis of Group-pile Foundation Subjected to Horizontal Cyclic Loading
Jin, Young-Ji ; Kim, Tae-Hoon ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 199~204
DOI : 10.9798/KOSHAM.2014.14.4.199
It is critical to predict the behaviors of between the group-pile foundations and superstructures during large magnitude of earthquakes. In this research, 3D numerical analysis of real-scale group-pile foundation subjected to horizontal cyclic loading is conducted by using DBLEAVES. In numerical analysis, nonlinear behaviors of between ground and piles are predicted through cyclic mobility model and axial force dependent model(AFD model), respectively. This research is objected to prove availability of the analysis method by comparing numerical results and field test results.
Development of Risk Prediction Model for Debris Flow Combining Physical Impact and Social Vulnerability
Woo, Choongshik ; Lee, Changwoo ; Kim, Kyongha ; Kwon, Hyunjung ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 205~212
DOI : 10.9798/KOSHAM.2014.14.4.205
Recently, the loss of life and property is increasing by debris flow that is occurring very often in urban zone near mountainous area. However, because most studies have only focused on prediction of landslide occurrence and damage area by debris flow, the study on risk prediction reflecting a social vulnerability is demanded. In this study, we developed the risk prediction model for debris flow that was combined with physical impact(magnitude) of debris flow and social vulnerability. The risk of combining magnitude and vulnerability for debris flow was classified 1~5 grades according to dangerous degree, and the 1st grade is most dangerous. Using this model, the case study adapting Yongin city, Gyeonggi province shows that 1st grade are 2 sites, 2nd grade are 40 sites, 3rd grade are 60 sites, 4th grade are 124 sites, 5th grade are 53 sites. To compare this model by preceding research, we adapted to Mt. Umyeon which was damaged by debris flow in 2011. As a result, the risk of debris flow on this area was shown in 2nd grade on each model.
Conceptual Inquiry and Policy Challenges on Disaster Management 3.0
Rheem, Sangkyu ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 213~222
DOI : 10.9798/KOSHAM.2014.14.4.213
Theses days the intensity and the frequency of disaster became unpredictable due to the rapid urbanization and abnormal changes of weather. Therefore, the cooperative inter-agency disaster management is more important than anything in the event of a complex disaster. President Park has emphasized "Government 3.0" the open system of ICT-based sharing, communication and cooperation. As the starting to build a governance system of cooperative disaster management, this paper was to explore the concept of "disaster management 3.0" and the policy issues. The disaster management 3.0 can be defined to build a cooperative framework of disaster management between entities, and to implement a consumer-oriented disaster management system which is to collect disaster information, increase their value, and share in real-time by utilizing ICTs. In addition to this, it is needed to proliferate disaster management 3.0. First, it is the development of disaster-related laws and regulations. Second, reducing the complexity of the disaster management system. Third, strengthening the sharing system of disaster information. Fourth, the expansion of professional human resources of disaster fields. Finally, the construction of organizational learning system based on the "Business Continuity Planning".
Analysis of the Effect of Land use on Forest Fires: Focused on Chungbuk Province Cases
Kim, Yu Ri ; Jo, Jin Hee ; Lee, Jae Hong ; Hwang, Hee Yun ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 223~232
DOI : 10.9798/KOSHAM.2014.14.4.223
The purpose of this study was to analyze land uses affecting spatial distribution patterns, and forest fire occurrence in forest fire areas using forest fire data of Chungbuk Province (1991 to 2012). For this purpose, this study examined spatial distribution patterns in forest fire areas using nearest neighbor index analysis, kernel density estimation and spatial autocorrelation analysis. Land use types affecting forest fire occurrence was induced by spatial regression analysis. As the result, forest fire occurrence in Chungbuk Province was spatially autocorrelated, and formed local clustering patterns. Land uses affecting forest fire occurrence were forest area, agricultural area and bare land. Forest fire in the area affects forest fire by 40.7%. Results of this study can be used to enhance monitoring system for forest fire prevention in forest fire areas, and help take preventive measures against forest fires by land use type significantly affecting forest fire occurrence.
A Study on the Disaster and Civil Defense of East Germany during the Course of Unexpected Reunification
Min, Se-Hong ; Kwon, Young-Hee ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 233~241
DOI : 10.9798/KOSHAM.2014.14.4.233
In 1949 after World War, Germany was divided into East German and West German. In year 1990, the east and west re-united together. During the course of reunification, the country has progressively transformed civil defense of national security into disaster prevention system in accordance with world peace and cooperation trends. Henceforth, this research is centered on factors that have promoted successful reunification in Germany such as reunification process, policy, organization & re-organization, role & responsibility analysis, work scope, and network with related entities. Based on above factors, the purpose of this research is to extract fundamentals that are crucial to reunification in Korea and to develop disaster safety management system. Firstly, research should be made on institutional integration and this requires realistic and systematic approach. Secondly, it is required to take proactive measures such as consistent communication with private entities and expansion of network. Thirdly, it is required to re-develop realistic unit for reunification. Fourthly, it is advised to contemplate unnecessary waste factors of budget overrun and excessive investments on facilities that are arisen from facilitating communication channel between South and North Korea. Fifthly, it is advised to implement strategy to timely manage over disaster prevention and postal measures by building lateral and longitudinal collaboration relationship.
Deterministic Evaluation for Insurance of Fire Safety in Nuclear Power Plant
Cho, Namjin ; Yun, Kiyul ; Cho, Kyoungrae ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 243~248
DOI : 10.9798/KOSHAM.2014.14.4.243
Because nuclear power plant is special facilities might cause massive damage by inducing shut-down of nuclear reactor and impairing equipment for safe shut-down in case of fire incident in it, it should be required special design condition for fire safety different from general industrial facilities. In this study, we`d like to forecast fire behavior in main control room of nuclear power plant through fire modeling. CFAST, well-known for zone model is applied As fire analysis model method for fire safety evaluation in main control room and fire simulation is executed on basis of NUREG/CR-6850. Through analyzing height of hot gas layer, temperature, radiation heat, optical density, as a result, we evaluated egress time in case of fire incident. Also, we hope to offer information for evaluation and insurance of fire safety in nuclear power plant.
Seismic Fragility Evaluations of PSC Box-girder Bridges Using Capacity Spectrum Method
Kim, Gwang Jeon ; Song, Jong-Keol ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 249~259
DOI : 10.9798/KOSHAM.2014.14.4.249
Most of existing seismic fragility analysis have been performed using the response history analysis (RHS). It takes many times to calculate inelastic seismic response for a structural system with many structural members during a ground motion. Since seismic fragility analysis are evaluated using many ground motions, it is time consuming process. If the more simple seismic analysis method can be used to seismic fragility analysis, these analysis efforts can be reduced. In this study, the capacity spectrum method (CSM) as simple seismic analysis method is used to evaluate seismic fragility of PSC box-girder bridges. The seismic fragility curves calculated by using RHA and CSM are compared.
Application of Principal Component Analysis in the Evaluation of the Damages Incurred by Ondoy and Perpeng`s Lash to Philippines
Necesito, Imee V. ; Yu, Insang ; Jeong, Sangman ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 261~266
DOI : 10.9798/KOSHAM.2014.14.4.261
One of the adverse impacts of climate change is excessive rainfall patterns, most of the time creating flood disasters. Flood disaster is one of the most serious natural hazards for human societies which cause damages to properties as well as loss of human lives thus creating great impacts on the economic status of the state. A country, such as the Philippines, which is bounded by limited funds, is most likely to have a public outcry in times of catastrophes like intense floods. This paper examines the impacts of the 2009 Ondoy and Pepeng flood as well as used principal component analysis to derive components that were capable of explaining the 79.38% of the total variance in the flood damage. Data from the studies funded by the different institutions both local and international were used in order to evaluate the damages and losses on the economic and social perspective of the country during the said two catastrophic events.
A Study on the Monthly Trend of Seoul Hourly Rainfall Using BLRPM
Hwang, Seok Hwan ; Ham, Dae Heon ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 267~278
DOI : 10.9798/KOSHAM.2014.14.4.267
In this study, Quantative long-term change characteristics of generated hourly short-term rainfall were analyzed through the disaggration of daily rainfall which are include Chukwooki rainfall of Seoul into hourly rainfall and then re-aggragation of the hourly rainfall by duration. From the analysis of transition probabilities and occurance fequencies of generated rainfall, modern rain gage data set(MRG)`s mean lengths of dry spells are increased and mean lengths of wet spells are decreased compared to Chukwooki data set(CWK). this means that rainfall durations of these days are shorter than past. And rainfall intensities of these days are much increased than past when considered with quantative increment of rainfall. From results of comparisons for the ratios of means and variances of generated durational rainfall which are classified with pre- and post- A.D. 1960, Increasing rates of September are greastest over all and August also shows the great Increasing rate relatively. But June shows the decreasing trend.
Estimation of Sediment Yield Using Total Sediment Yield Formulas and RUSLE
Lee, Minhyung ; Yu, Insang ; Necesito, Imee V. ; Kim, Hayong ; Jeong, Sangman ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 279~288
DOI : 10.9798/KOSHAM.2014.14.4.279
Gyeongan stream, the first tributary of Han River in Korea, flows into Paldang Lake providing potable water to 23 million people living in the Seoul Metropolitan area. This stream is shallow and discharges small amount of water which adds up to the accumulation of floating matter. The water flowing into the lake worsens the discharge capacity and the water quality of the basin. It also reduces its storage capacity, a threat to the water supply function. For these reasons, it is necessary to quantitatively investigate the sediment load flowing into Paldang Lake from Gyeongan stream to come up with a countermeasure. In this study, a quasi-sediment rating curve was developed using the 2008 to 2010 total sediment load. Total sediment load was estimated based on the data of suspended load measured at Gyeongan stream basin. Taking into account the existing Sediment Delivery Ratio (SDR) equation of soil loss calculated by Revised Universal Soil Loss Equation (RUSLE) and the equation of sediment yield, a comparative analysis between the actual measured data and the latter was executed. The results showed that the sediment yield calculated using Ackers and White`s total sediment load equation and Vanoni`s RUSLE by SDR are almost similar with quasi-sediment rating curve. Their relative errors of total sediment according to Ackers and White and Vanoni`s RULSE were calculated to be 6.4%~13.5% and 8.1%~12.0% respectively. This indicates the feasibility of estimating sediment yield using Ackers and White`s total sediment load equation and Vanoni`s SDR.
Operation of Estuary Barrage and Weirs in the Nakdong River during the Flood Period
Kim, Min Ji ; Min, Kyung Tae ; Jun, Kyung Soo ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 289~299
DOI : 10.9798/KOSHAM.2014.14.4.289
A numerical model was developed that can simulate gate openings of estuary barrage and a series of weirs as well as the unsteady flow during the flood period in the Nakdong River. It is a multiply-connected network model based on the Preissmann`s four-point scheme and the Newton-Raphson method. The computational model can appropriately simulate composite flows at multi-functional weirs including weir overflow, orifice-type flow, and fluvial-type flow. Gate operation strategies for the weirs and the estuary barrage were established such that gates be closed for water level below a certain reference level and gate openings increase as the water level rises. Ad-hoc operating condition for the drainage gate of the Nakdong Estuary Barrage is to close the gates if the inner water level is lower than the sea water level. The prescribed operation conditions were well simulated by the model, and sensitivities to the parameters of the gate operation strategy were analyzed.
Temporal Downscaling of Precipitation from Daily to Hourly Based on Nonparametric Approach: Assessment of the Climate Change Impacts on the Hourly Precipitation for the Gyeongnam Region
Lee, Taesam ; Park, Taewoong ; Lee, Hyunseung ; Jeong, Changsam ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 301~308
DOI : 10.9798/KOSHAM.2014.14.4.301
Hourly hydro-meteorological data are vital to flood control system and to assess the hydrological effects of climate change on medium and small watersheds. However, finder than daily hydro-meteorological data are not easy to obtain. A temporal downscaling method to obtain finer time series, e.g. hourly, might be very useful for assessing the hydrological effects of the variations of precipitation by climate change. In the current study, a temporal downscaling model that combines a nonparametric stochastic simulation approach with Genetic Algorithm (GA) is tested. The tested model was applied to Busan-Gyeongnam station in South Korea for a historical time period to validate the model performance. The results revealed that the applied model preserves the key statistics (i.e., the mean, standard deviation, skewness, lag-1 correlation, and maximum) of the historical hourly precipitation data. Furthermore, the RCP 4.5 and RCP 8.5 climate scenarios for the Busan-Gyeongnam area were also analyzed. The results illustrated that the mean significantly increased while the standard deviation and maximum slightly increased in these scenarios. The magnitude of the increase was greater in RCP 8.5 than RCP 4.5. The downscaled hourly precipitation adequately reproduced the statistical behaviors of the historical hourly precipitation data for all durations considered. Overall, the results demonstrated that the applied temporal downscaling model is a good alternative method for downscaling simulated daily precipitation data to hourly especially for assessing the impacts of climate change especially from the variations of precipitation.
Evaluation of Stream Gauge Network Considered Discharge Characteristics Between Upstream and Downstream of the River
Kim, Soojun ; Joo, Hong Jun ; Lee, Jiho ; Jun, Hwandon ; Kim, Hung Soo ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 309~319
DOI : 10.9798/KOSHAM.2014.14.4.309
This study has evaluated the stream gauge network with the main emphasis on the methodology of optimal stream network which is considered the discharge characteristics between upstream and downstream. To evaluate the optimal stream gauge network, the representative unit hydrograph which is considered the discharge characteristics between upstream and downstream is transferred into probability density function for application of the entropy concept. This study has been compared the case of considering discharge characteristics between upstream and downstream and the case of the conventional methodology of using empirical formula and applied to the Chungju dam basin. Summarizing the results are as follows. It can be found that the large total information content is estimated at the case which is considered discharge characteristic between upstream and downstream more than the case which is applied empirical formula even though the few stream gauge stations is selected. It means that the total information of selected stream gauge stations is represented well the discharge characteristic between upstream and downstream. The Chungju dam basin is found to need at least 12 stream gauge stations, which was derived by considering the discharge characteristic between upstream and downstream.
A Comparative Analysis on the Flood Reduction Effects of Stormwater Storage and Infiltration Measures at a Catchment Scale
Park, Changyeol ; Shin, Sang Young ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 321~332
DOI : 10.9798/KOSHAM.2014.14.4.321
The purpose of this study is to evaluate the flood reduction effects of stormwater storage and infiltration facilities at a urban catchment scale and to compare the cost-effectiveness with drainage system improvements. Three policy scenarios to mitigate flood damage were developed by considering drainage system improvements, storage installations, and infiltration facility installations. The installation costs and flood reduction effects of the scenarios were compared to each other. The result shows that, while the stormwater storage and infiltration facilities were marginally effective in reducing the amount of peak flow and runoff volume, they were more effective in reducing the inundation damage. As rainfall increases, the cost-effectiveness of drainage improvements measures decreases relatively, yet the cost-effectiveness of stormwater storage and infiltration facility measures increases remarkably. This result indicates that stormwater storage and infiltration facilities could be helpful to mitigate urban flood risk more fundamentally as local heavy rainfall increases.
Simulation of Long-term Reservoir Sedimentation and Flushing
Noh, Joonwoo ; Lee, Kyungsu ; Hur, Youngteck ; Kim, Youngsung ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 333~341
DOI : 10.9798/KOSHAM.2014.14.4.333
This paper presented long-term reservoir sedimentation in the Patrind Reservoir of Pakistan and evaluation of the sediment flushing based on the gate operation corresponding to the upstream discharge and sediment inflow using EFDC 3 dimensional hydrodynamic model. Simulated for five years, the invert level in the middle reach of the reservoir increased up to 10m without flushing, while 5 days flushing after the peak flow in each year contributes to release accumulated sediment through flushing gate. Sediment flushing occurs mainly through the channel formulated during flushing operation. From the results of EFDC simulation it is possible to estimate the fraction of the particle size distribution which exceed 0.2 mm deposited in front of the intake facility since it is known to result in significant turbine damage. The results of this study will contribute to establish a sound reservoir operation plan considering efficient sediment management.
Performance Evaluation of Multi-Arrayed Submerged Structures by Impermeable Depositional Topography
Lee, Jun-Whan ; Cha, Jun-Ho ; Cho, Yong-Sik ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 343~349
DOI : 10.9798/KOSHAM.2014.14.4.343
The deposition between the two adjacent submerged structures over a long time can decrease the roles of structures and also threaten the safety of the coastal communities. In this study, the reflection of the incident water waves caused by deposition among multi-arrayed submerged structures are investigated by using the eigenfunction expansion method. The proper number of the steps representing a slope and the evanescent modes for calculating the reflection coefficient was suggested, and the resulting reflection coefficients were compared with the previous results. Not only the performance change due to difference styles of deposition and the amount of deposition between multi-arrayed submerged structures, but also the characteristic changes in the Bragg reflection caused by the deposition were studied. We found that the depositional topography affects the performance of multi-arrayed submerged structures. Thus, when designing multi-arrayed submerged structures, we have to consider the performance change by deposition.
Numerical Simulation of Sea Bed Morphological Change due to Sediment Transport by Tsunami
Lee, Ja-Hoon ; Park, Jin Won ; Cho, Yong-Sik ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 351~359
DOI : 10.9798/KOSHAM.2014.14.4.351
Tsunami, one of the major natural disasters, is rapidly invaded the coastal communities resulting in significant casualties of human beings and property damage. In addition, because tsunamis may have a great amount of energy, they transport various floating debris and silt resulting a deformation of the coastline and a damage to structures. Therefore, predicting the sediment transport caused by tsunami is also important as much as expecting the inundated area due to flooding. In this study, a numerical simulation is carried out to predict the morphological change of the sea bed considering the domain, where sediment transport occurs, into two layers; bed load layer which is made up by bed load, and suspended load layer mainly composed by the movement of the suspended load.
Evaluation of Various Design Configurations of a Tree Box Filter Treating Urban Runoff using SWMM
Tobio, Jevelyn Ann S. ; Maniquiz-Redillas, Marla C. ; Kim, Lee Hyung ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 361~367
DOI : 10.9798/KOSHAM.2014.14.4.361
In this research, the physical characteristics (e.g. surface area and storage volume) of an existing tree box filter treating urban runoff were adjusted using stormwater management model (SWMM) to determine the most suitable design configuration and installation (e.g. centralized, series or parallel). The storage volume (SV) and surface area (SA) of the facility was increased or decreased by an increment of 25% (original value is 0.45). These simulations would predict the influence of larger or smaller SV or SA with respect to the facility performance. The hydrologic, hydraulic and water quality data used in the modelling were gathered from the 10 storm events monitored from July 2012 to July 2013. The total suspended solids were considered as the main target pollutant and will be correlated with the common heavy metal constituents. Both parallel and series distributed system has improved the treatment performance by at least of 30% on both volume and particulate removal. However, the mentioned configurations would require additional maintenance and operation costs. Thus, the modelled centralized system would provide better volume and pollutant reduction than a distributed system.
Effectiveness Analysis of Artificial Wetland for Flood Reduction
Jung, Jae Won ; Kim, Yon Soo ; Hong, Seung Jin ; Kwon, Hyung Soo ; Kim, Jung Wook ; Kim, Hung Soo ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 369~377
DOI : 10.9798/KOSHAM.2014.14.4.369
Wetlands have various functions such as water purification, disaster management, habitat of creature, climate change management, etc. Constructed wetland has been introduced as an alternative especially for flood control in the river basin, because it can reduce flood stage as well as improve water quality. However, the previous studies only focused on the function of water quality improvement and ecological function of biodiversity, and the studies on the flood control effects according to artificial wetlands including channel-type wetlands have not yet been carried out. In this study, we compared and analyzed the flood inundation by doing comparative analysis on flood level change before and after creation of constructed wetlands. For this study, outflow of study area were calculated using HEC-HMS model, and we investigated the change in flood stage before and after creation of constructed wetlands using HEC-RAS model by modeling artificial wetland. The results showed that flood stage after wetland construction was decreased and the reduced stages were maximum 0.81 m, average 0.11 m when we compared with flood stage before wetland construction. Also, flood inundation mapping results showed that the total area of inundation was also decreased in about
after wetland construction, and so this study has shown that the artificial wetland can reduce flood stage in Mokgamcheon basin.
Analysis of Head Loss Coefficient for Non-point Pollutants Removal Equipments with Branch Angle and Cross-section Ratio of Inflow Channel
Song, Youngseok ; Lee, HeeSub ; Park, Minkyu ; Park, Moojong ;
Journal of Korean Society of Hazard Mitigation, volume 14, issue 4, 2014, Pages 379~385
DOI : 10.9798/KOSHAM.2014.14.4.379
Various NPS (Non-Point Sources) pollutants flow into a stream after rainfall event that directly causes water quality deterioration. NPRE (Non-point Pollutants Removal Equipments) is necessarily emphasis for water quality improvement. Existing installed NPRE only consider conditions of location or digestion capacity that causes low removal efficiency. In this study, head loss coefficient are analyzed by branch angle and ratio of channel flow area of inflow channel when polluted stream water flows in NPRE. Branch angle of inflow channel (
) and entrance channel on ratio of channel flow area of inflow channel (20%, 30%, 40%) are analyzed Using Two-dimensional hydraulic modeling. Result from decreasing branch angle of inlet and increasing entrance channel on ratio of channel flow area of inlet that showed decreasing head loss coefficient.