• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1042-1046
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• 2008

Both the weighing bridge and the diverter system is a important component in achieving a high accuracy liquid flow rate standard using a static gravimetric method. The weighing bridge is a tank which weighing collected flow with a load cells. The diverter is a moving device used to direct flow alternately along its normal course(by pass) or towards the weighing tank. The time needed for collection into the weighing tank is measured using a timer. So it is important to the diversion period is sufficiently fast and triggering point of timer which is determined the filling time. On this studies show that the measurement deviation of load cell and uncertainty of diverter system for changing diversion speed and triggering point was estimated in accordance with Guide to The Expression of Uncertainty in Measurement(ISO).

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.45-52
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• 1999

In this study, a new bridge rail system is proposed to prevent large vehicles from running off the bridge edge. The crush model has accounted for the effects of both curbs and bridge rails which are simulated by Highway Vehicle Object Simulation Model(HVOSM) and BARRIER VII. Vehicle sizes ranged from minicars weighing 1800kg to large vehicles weighing 14000kg, and impact angles ranged from 15$^{\circ}$ to 25$^{\circ}$.

• Journal of Korean Society of Steel Construction
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• v.11 no.2 s.39
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• pp.223-232
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• 1999

For the design and maintenance of highways and road structures, the statistical data are needed for the vehicle, especially heavy truck crossing. So far, static weighing has been used but it needs fixed station, crews, and it takes a lot of time. Also truck mix and headway distances cannot be obtained. Bridge Weigh-In-Motion system uses the bridge as a weighing scale and collects the axle weights, axle distances. vehicle types and etc. without stopping or slowing down the vehicle. In this study, for the first time in the country, BWIM system is applied on steel I-girder bridge and its applicability is examined. Also data collected in this system is analyzed to get truck traffic characteristics including average daily truck traffic, weight distribution, typical truck configuration and overweight truck status. The results are compared with other data from weighing station and highway toll gates.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.295-296
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• 2008

• Smart Structures and Systems
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• v.6 no.3
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• pp.277-290
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• 2010

Internationally the load carrying capacity of bridges is decreasing due to material deterioration while at the same time increasing live loads mean that they are often exposed to stresses for which they were not designed. However there are limited resources available to ensure that these bridges are fit for purpose, meaning that new approaches to bridge maintenance are required that optimize both their service lives as well as maintenance costs. Wireless sensor networks (WSNs) provide a tool that could support such an optimized maintenance program. In many situations WSNs have advantages over conventional wired monitoring systems in terms of installation time and cost. In order to evaluate the potential of these systems two WSNs were installed starting in July 2007 on the Humber Bridge and on a nearby approach bridge. As part of a corrosion prevention strategy, a relative humidity and temperature monitoring system was installed in the north anchorage chambers of the main suspension bridge where the main cables of the bridge are anchored into the foundation. This system allows the Bridgemaster to check whether the maximum relative humidity threshold, above which corrosion of the steel wires might occur, is not crossed. A second WSN which monitors aspects of deterioration on a reinforced concrete bridge located on the approach to the main suspension bridge was also installed. Though both systems have provided useful data to the owners, there are still challenges that must be overcome in terms of monitoring corrosion of steel, measuring live loading and data management before WSNs can become an effective tool for bridge managers.

• Journal of Applied Reliability
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• v.16 no.2
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• pp.90-97
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• 2016

Purpose: Majority of bridges and roads in Gangwon Province have been carrying loads associated with heavy materials such as rocks, mining products, and cement. This location-specific live loads have contributed to the present situation of overloading, compared to other provinces in Korea. However, the bridges in Gangwon province are designed by national bridge design specification, without considering the location-specific live load characteristics. Therefore, this study focuses on the real traffic data accumulated on regional weighing station to verify the live load characteristics, including actual live load gross vehicle weight, axle weight axle spacings, and number of trucks. Methods: In order to take into account the location specific live load, a governmental weigh station (38th national highway Miro) have been selected and the passing truck data are processed. Based on the truck survey, trucks are categorized into 3 different shapes, and each shape has been idealized into normal distribution. Then, the resulting survey data are processed to predict the target maximum live load values, including the axle loads and gross vehicle weights in 75 years service life span. Results: The results are compared to the nationally used DB-24 live loads, and the results show that nationally recognized DB-24 live load does not sufficiently represent real traffic in mountaineous region in Gangwon province. Conclusion: The comparison results in the recommendation of location-specific live load that should be taken into account for bridge design and evaluation.

• Interaction and multiscale mechanics
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• v.5 no.1
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• pp.41-56
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• 2012

This study is focused on evaluation of the tensile properties of concrete exposed to acid rain environment. Acid rain environment was simulated by the mixture of sulfate and nitric acid in the laboratory. The dumbell-shaped concrete specimens were submerged in pure water and acid solution for accelerated conditioning. Weighing, tensile test, CT, SEM/EDS test and microanalysis were performed on the specimens. Tensile characteristics of the damaged concrete are obtained quantitatively. Evolution characteristics of the voids, micro cracks, chemical compounds, elemental distribution and contents in the concrete are examined. The deterioration mechanisms of concrete exposed to acid rain are well elucidated.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.488-493
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• 2005

Railload line design of the railroad construction project should be planed considering the variety of quantitative and qualitative factors, and needs to be selected the optimum altinative weighing from VE/LCC analysis of the planned design. The purpose of this research is for showing selecting plan of the optimum railload line and railway bridge applying VE/LCC analysis in selecting the optimum altinative of railroad construction based on quantitative and qualitative factors, such as initial construction cost, maintenance cost, owner and user's requirements. In this research showed the application plan by each stage using data analysis, function analysis, and alternative evaluation of VE/LCC analysis with AHP and LCC analysis program for the selection. This research is proved the rationality and application of the course of selecting the optimum alternative through case application

• Journal of Korean Society of Steel Construction
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• v.17 no.6 s.79
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• pp.727-736
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• 2005

This study presents a method of determining the optimum cable tension forces for the proper initial equilibrium state of a cable-stayed bridge using the least square method. The proposed method minimizes the errors, i.e., the differences, such as the deflection and the moments of the girder and the tower, between the target values from a continuous beam by considering the cable anchor point as supports of the girder and the responses obtained from the analysis of the entire cable-stayed bridge system. Especially, the proposed method can selectively control the adjustment of the tower moment, the girder moment, and the deflections by introducing the weighing matrix. Through numerical analysis and comparisons with existing studies, the usefulness and validity of the proposed method was verified.

• Structural Monitoring and Maintenance
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• v.9 no.1
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• pp.43-57
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• 2022

One of the instances which demand structural engineer's greatest attention and upgradation is the changing live load requirement in bridge design code. The challenge increases in developing countries as the pace of infrastructural growth is being catered by the respective country codes with bigger and heavier vehicles to be considered in the design. This paper presents the case study of India where Indian Roads Congress (IRC) codes in its revised version from 2014 to 2017 introduced massive Special vehicle (SV) around 40 m long and weighing 3850 kN to be considered in the design of road bridges. The code does not specify the minimum distance between successive special vehicles unlike other loading classes and hence the consequences of it form the motivation for this study. The effect of SV in comparison with Class 70R, Class AA, Class A, and Class B loading is studied based on the maximum bending moment with moving load applied in Autodesk Robot Structural Analysis. The spans considered in the analysis varied from 10 m to 1991 m corresponding to the span of Akashi Kaikyo Bridge (longest bridge span in the world). A total of 182 analyses for 7 types of vehicles (class B, class A, class 70R tracked, class 70R wheeled, class AA tracked, AA wheeled, and Special vehicle) on 26 different span lengths is carried out. The span corresponding to other vehicles which would equal the bending moment of a single SV is presented along with a comparison relative to Standard Uniformly Distributed Load. Further, the results are presented by introducing a new parameter named Intensity Factor which is proven to relate the effect of axle spacing of vehicle on the normalized bending moment developed.