• Journal of the Korean Society of Safety
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• v.24 no.6
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• pp.119-123
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• 2009

The purpose of this study is to verify the assessment of the risk index by the AHP method effective in the bridge construction. We compared that by the AHP method with the risk index by the accident analysis in the bridge construction. This method results in the useful tool deciding the assessment of the risk index according to work type in the bridge construction.

• Structural Engineering and Mechanics
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• v.41 no.1
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• pp.83-94
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• 2012

Assessment of a monumental concrete arch bridge with a total length of 210 meters having three major spans of 30 meters and a height of 65 meters, which is located in an earthquake-prone region in southern part of the country is presented in this study. Three-dimensional finite element model of the bridge was generated using a commercially available general finite element analysis software and based on the outcomes of a series of in-depth acceleration measurements that were conducted on-site, the model was refined. By using the structural parameters obtained from the dynamic and the static tests, calibrated model of the bridge structure was obtained and this model was used for necessary calculations regarding structural assessment and evaluation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.7
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• pp.1111-1119
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• 2022

Tourism projects through islands in the waters of Sinan-gun became active, and as a result, a total of 13 marine bridges connecting islands were completed. However, the marine bridge constructed in the fairway is dangerous for traffic. Particularly, in the case of the marine bridge connecting two islands, the width of the fairway is extremely narrow, therefore the risk is higher. In this study, we evaluated the risk of collision between marine bridge piers and ships using the IALA Waterway Risk Assessment Program (IWRAP), a risk assessment model for port waterways, based on a maritime traffic survey on the coastal bridge in Sinan-gun. The results, indicated that No.1 Sinan bridge had the highest probability of collision and most of the transit ships were coastal passenger ships. In addition, No.1 Sinan bridge was the place where the most collision accidents occurred among the marine bridge piers in the target sea, and the cause this study was analyzed. An analysis of the satellite images of the sea environment of No.1 Sinan bridge using an image processing method, confirmed that obstacles that could not be seen in the chart existed nearby the bridge. As a result, traffic was observed to be concentrated in one direction, unlike two-way traffic, which is a method of inducing traffic of bridges to avoid obstacles. The risk cause analysis method using the image processing technique of this study is expected to be used as a basic research method for analyzing the risk factors of island bridge in the future.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.79-86
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• 1999

This paper aims to propose a method that helps maintenance engineers to evaluate the damage states of bridge systems by using a Fuzzy Fault Tree Analysis(FFTA). It may be stated that Fuzzy Fault Tree Analysis may be may useful for the systematic md rational condition and safety assessment for real bridge systems problems because the approach is able to effectively deal with all the related bridge system damages in terms of the linguistic variables that incorporate systematically experts experiences and subjective judgement.

• KCI Concrete Journal
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• v.11 no.3
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• pp.109-114
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• 1999

Recently the interest in the safety assessment of civil infrastructures has increased. As bridge structures become large-scale, it is necessary to monitor and maintain the safety of large bridges, which requires smart systems that can make long-term monitoring a reality . Civil engineers have applied monitoring systems to several bridges, such as the New Haeng-Ju Bridge and Riverside Urban Highway Bridge, but these applications have some problems with the sensors for long-term measurement, setup techniques for the bridge monitoring system and the assessment of measured data. In the present study, an optical fiber sensor smart system was tested and confirmed in laboratory tests on the concrete members. By Attaching optical fiber sensors to the structural parts of the Sung-San Bridge, the bridge load test was measured. These smart concrete structure systems can be applied to bridges and the load capacity of the bridge can assessed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.4
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• pp.423-429
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• 2017

As invigoration plan of the marine tourism, Busan City has the plan to operate the cruise ship inside of the harbor, but the area has narrow water way with heavy traffic. As a result it is requested to evaluate the safety for the preparation of actual navigation. In this study, the Ship Handling Simulation (SHS) Assessment was conducted, which is regulated by the Maritime Traffic Safety Audit Scheme (MTSAS) in compliance with the Marine Safety Law and the Maritime Traffic Risk Assessment System based on the Electronic Chart Display and Information System (ECDIS). The proximity assessment, control assessment and subjective assessment were implemented, which is enacted by the Marine Safety Law by using the SHS. In the case of proximity assessment, the probability of trespass was not analyzed. As the control assessment, the swept path was measured at 11.7 m and 11.5 m for port entry and port departure respectively, which exceeded the width of the model vessel, 10.4 m over; it was considered as a marginal factor. As a result of the subjective evaluation of the navigator, there would be no difficulty on ship maneuvering by paying particular attention to the mooring vessel nearby the Busan Bridge and Yeongdo Bridge as well as the coming vessel from the invisible sea area when the vessel is entering and departing the port. The Marine Traffic Risk Assessment System analyzed as [Cautious] level until the vessel passed the Busan bridge and the curved area at 5 kts and it became to [Dangerous] level from where it left 75 m to the Busan Bridge. When the vessel passed the Busan Bridge and the curved area at 10 kts and entered the narrow area, it indicated the [Dangerous] level and became to [Very dangerous] level from where it left 410 m to the Busan bridge. In conclusion, the vessel should maintain at the speed of 5 kts to reduce the risk when it passes this area.

• Smart Structures and Systems
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• v.19 no.2
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• pp.225-236
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• 2017

Railroad bridges in North America are an integral but aging part of the railroad network and are typically only monitored using visual inspections. When quantitative information is required for assessment, railroads often monitor bridges using accelerometers. However without a sensor to directly measure displacements, it is difficult to interpret these results as they relate to bridge performance. Digital Image Correlation (DIC) is a non-contact sensor technology capable of directly measuring the displacement of any visible bridge component. In this research, a railroad bridge was monitored under load using DIC and accelerometers. DIC measurements are directly compared to serviceability limits and it is observed that the bridge is compliant. The accelerometer data is also used to calculate displacements which are compared to the DIC measurements to assess the accuracy of the accelerometer measurements. These measurements compared well for zero-mean lateral data, providing measurement redundancy and validation. The lateral displacements from both the accelerometers and DIC at the supports were then used to determine the source of lateral displacements within the support system.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.185-195
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• 2017

In recent years, unexpected bridge fire accidents have increased because of augmenting the number of traffic volumes and hazardous materials by the increment in traffics and distribution business. Furthermore, in accordance with the effort of using the under space of bridges, the ratio of occupied by combustible materials like oil tanker or lorry has been increased. As a result, the occurrence of bridge fire has been growing drastically. In order to mitigate the accident of bridge fire, risk assessment of bridge fire has been studied, however, practical risk models considering safety from users' viewpoints were scarce. This study represented quantitative risk assessment model applicable to national road bridges in Korea. The primary factors with significant impacts on bridge fire accidents was chosen such as clearance height, materials of bridges, arrival time of fire truck and fire intensity. The selected factors were used for Fire Dynamics Simulation (FDS) and the peak temperature calculated by FDS in accordance with the fire duration and fire intensity. The risk assessment model in bridge fire reflected the FDS analysis results, the fire damage criteria, and the grade of fire truck arrival time was established. Response plans for bridge fire accidents according to the risk assessment output has been discussed. Lastly, distances between bridges and fire stations were calculated by GIS network analysis. Based on the suggested assessment model and methodology, sample bridges were selected and graded for the risk assessment.

• Structural Engineering and Mechanics
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• v.13 no.4
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• pp.455-464
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• 2002

There is a growing demand to assess the remaining strength and endurance of existing composite steel and concrete bridge beams due to the aging infrastructure, increases in permissible vehicle weights and increases in their frequencies. As codes are generally dedicated to the design of new structures, new procedures are required to aid in the assessment of existing bridges to ensure that they are utilised to the full. In this paper, simple expressions are presented to perform partial-interaction analyses directly from full-interaction analyses, so that the beneficial effect of partial-interaction on the shear forces on the shear connectors can be utilised in assessment to extend the fatigue life of simply supported bridge beams and to determine the effect of remedial work if necessary. Use of the assessment technique is described by way of an illustrative example.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.209-216
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• 2004

In A bridge which connects Mokpo North Harbor and Com Island is going to be constructed until 2009. For the bridges being built in the navigable water area, it is indispensible to carry out vessel traffic safety assessment from the viewpoint of shiphandlers, however, there exist no specific guidelines for the necessary conditions whim the bridge designers can rely on. In this paper, traffic safety assessment procedures for the layout of the bridge is briefly introduced, and the conditions whim should be taken into account at the initial design stage of the bridge is surveyed. For the safety assessment of the bridge design, ship navigation simulations, such as RTS(real time simulation} and FTS(fast time simulation), are carried out, the results of which are statistically analysed to estimate the probability of collision between the ship and the pier of the bridge.