• Geomechanics and Engineering
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• v.14 no.6
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• pp.601-614
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• 2018

This study presents structural and parametric analyses on the behavior of an integrated and pile-bent abutment with mechanically stabilized earth wall (IPM) bridge. The IPM bridge is an integral abutment bridge (IAB) with partially protruded piles, which excludes earth pressure by means of a mechanically stabilized earth wall developed by the authors. The results of the analysis indicate that the IPM bridge, as any other IAB, is influenced to a large extent by temperature and time-dependent loads. When these loads are applied, the stress on a pile in the IPM bridge decreases as the displacement of the pile top increases, because the piles protrude from the ground surface and no soil reaction is generated on the protruded pile. Because the length of an IAB is restricted by the forces acting on its piles, the IPM bridge is an effective alternative to extend its length.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1691-1696
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• 2010

Jeong-Ji overbridge is designed to be 9.3km long, the longest for a high speed railway bridge ever constructed in Korea. This bridge is constituted of three types of structure. Standard type bridge is 35m PSC Box bridge which will be constructed by Precast Span Method. To cross the Cheonan Nonsan Expressway, 80m three-span steel arch bridge is designed to avoid rail expansion joint. Finally, Extradosed bridge is planned for high speed railway bridge for the first time in Korea based on originative and advanced design techniques. It is expected that this will contribute to the development of national technology for long-span high speed railway bridges.

• Smart Structures and Systems
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• v.14 no.2
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• pp.129-144
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• 2014

In this paper, a fuzzy inference system and an analytical hierarchy process-based online evaluation technique is developed to monitor the condition of the 32-km Donghai Bridge in Shanghai. The system has 478 sensors distributed along eight segments selected from the whole bridge. An online evaluation subsystem is realized, which uses raw data and extracted features or indices to give a set of hierarchically organized condition evaluations. The thresholds of each index were set to an initial value obtained from a structure damage and performance evolution analysis of the bridge. After one year of baseline monitoring, the initial threshold system was updated from the collected data. The results show that the techniques described are valid and reliable. The online method fulfills long-term infrastructure health monitoring requirements for the Donghai Bridge.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.493-496
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• 2008

In case of collapsed or damaged Servicing infrastructure, such as a bridge, tunnel, dam, a severe loss may have to be incurred. Therefore, infrastructure should not be designed and constructed properly but also maintained impeccably. This paper tried to build an intelligent bridge maintenance system that warn the people on bridge and control traffic in the danger. For the purpose, diverse wireless sensor fields are composed and structure's database is established. Also the paper develops a bridge maintenance program. Developed programme is regarded as a good tool to provide the utmost bridge management scenario, which is exactly correspondent with the demand and restraint by improving the present bridge management strategy.

• Corrosion Science and Technology
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• v.3 no.4
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• pp.166-171
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• 2004

Recent developments in Bridge Management Systems (BMS) and in Life-Cycle Cost (LCC) of bridges, have raised the need for evaluation procedure of future condition (Deterioration) of a bridge. Predicting future deterioration is not an easy task due to limited past data to extrapolate from and also due to difficulty in measuring actual deterioration such as section loss of steel on an actual steel bridge. Also, increase in live load and reduction of resistance are random variables, thus a probabilistic approach should be adopted for determining the future deterioration. Due to difficulties in evaluation of future deterioration on steel bridges, accepting uncertainties within a reasonable error, a deterministic procedure using bridge condition rating can be a useful tool for projection of future condition of bridges to identify repair and maintenance needs. The object of this paper is to determine applicability of evaluating deterioration of steel bridge components based on Bridge condition ratings. Bridge condition ratings of bridge components show wide variation for bridges of same age and does not directly correlate well with the age of the bridge and/or deterioration of the bridge. High uncertainty can be reduced by breaking down the rating and by sensitivity analysis. From refined condition rating data, generalized deterioration profile of structures based on age can be derived. Examples are shown for sample bridges in USA. Approximately, 3,000 short to medium span steel bridges were listed in the inventory database. Results show wide variation of rating factors but by subdividing the Bridge condition ratings for various categories general deterioration profiles of steel bridges can be determined.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.837-843
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• 1999

A common hydraulic jack using brdige retrofit has a problem of increasing cost and time of construction to construct additionally temporary bent or concrete bracket, in case of insufficiency work space and release hydraulic pressure. To solve the problem, this technique is developed to alternate the bridge bearing in adequate inspection condition. After control maximum lift-height and minimum lift-force of no damage to super structure, the constructive technique is to alternate and repair the bridge bearing using the wedge jack with bridge bearing ability that is no release hydraulic pressure stopper, and able to reuse separable cylinder.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2243-2244
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• 2008

In this paper, XLPE cable underneath a bridge is modelled using EMTP/ATPDraw. Bridge section is also modelled by mutually coupled parallel conductor with XLPE cable. This paper is analysed the overvoltge by structure change of bridge section when the lightning occurs on the system.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.1248-1253
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• 2005

The study is indispensable for the dynamic behaviors because this Cable-stayed long span bridge ; has a more flexible structure than normal bridge can have weaknesses which are impact factor, deflection and defectives etc. This study analyze the dynamic behavior by an analysis of the moving constant train force on railway with Midas/Civil that is a commercial finite element analysis tool about Extradosed PSC Bridge. Also it will be checked the dynamic behavior features and standard of the dynamic capability.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.481-484
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• 2008

The research was carried out to suggest the bridge health monitoring systems that have been composed damage detection algorithm and a system for evaluation load carrying capacity of bridge by traffic loads for the purpose of safety management of bridge structure in efficient and economic.

• Coupled systems mechanics
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• v.7 no.4
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• pp.485-507
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• 2018

The moving load causes the occurrence of vibrations in civil engineering structures such as bridges, railway lines, bridge cranes and others. A novel engineering method for separation of the variables in the differential equation of the elastic line of Bernoulli-Euler beam has been developed. The method can be utilized in engineering structures, leading to "a beam under moving load model" with generalized boundary conditions. This method has been implemented for analytical study of the dynamic response of the metal structure of a single girder bridge crane due to the telpher movement along the bridge girder. The modeled system includes: a crane bridge girder; a telpher, moving with a constant horizontal velocity; a load, elastically fixed to the telpher. The forced vibrations with their own frequencies and with a forced frequency, due to the telpher movement, have been analyzed. The loading resulting from the telpher uniform movement along the bridge girder is cyclical, which is a prerequisite for nucleation and propagation of fatigue cracks. The concept of "dynamic coefficient" has been introduced, which is defined as a ratio of the dynamic deflection of the bridge girder due to forced vibrations, to the static one. This ratio has been compared with the known from the literature empirical dynamic coefficient, which is due to the telpher track unevenness. The introduced dynamic coefficient shows larger values and has to be taken into account for engineering calculations of the bridge crane metal structure. In order to verify the degree of approximation, the obtained results have been compared with FEM outcomes. An additional comparison has been made with the exact solution, proposed by Timoshenko, for the case of simply supported beam subjected to a moving force. The comparisons show a good agreement.