• International Journal of Railway
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• 제7권1호
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• pp.16-23
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• 2014

Reduction in railway-induced vibrations in urban areas is a very challenging task in railway transportation. Many mitigation measures can be considered and applied. Among these, a little attention has been paid to trenches. In this study, a numerical investigation on the effectiveness of in-filled trenches with pipes in reducing railway vibrations due to passing trains is presented. Particularly, a series of two-dimensional dynamic analysis was performed to model the behavior of ballasted railway track under harmonic load with ABAQUS software as a Finite Element method. In so doing, two types of in-filled trenches with pipes with steel and concrete materials have been investigated in this paper. In addition, effectiveness of pipes made of steel and concrete, filled with loose sand and clay in railway-induced vibration reduction has been assessed. The results point out that using in-filled trench with pipes does not effective a lot on railway-induced vibration reduction in comparison to other railway-induced vibration reduction methods. However, in-filled trenches with steel pipes are much more effective than in-filled trenches with concrete pipes. Moreover, filling pipes with loose sand and clay does not have any effect on vibration reduction efficiency of these in-filled trenches.

• Structural Engineering and Mechanics
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• 제54권2호
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• pp.199-219
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• 2015

This paper presents the non-destructive evaluation of a high-speed railway bridge using train-induced strain responses. Based on the train-track-bridge interaction analysis, the strain responses of a high-speed railway bridge under moving trains with different operation status could be calculated. The train induced strain responses could be divided into two parts: the force vibration stage and the free vibration stage. The strain-displacement relationship is analysed and used for deriving critical displacements from theoretical stain measurements at a forced vibration stage. The derived displacements would be suitable for the condition assessment of the bridge through design specifications defined indexes and would show certain limits to the practical application. Thus, the damage identification of high-speed railways, such as the stiffness degradation location, needs to be done by comparing the measured strain response under moving trains in different states because the vehicle types of high-speed railway are relatively clear and definite. The monitored strain responses at the free vibration stage, after trains pass through the bridge, would be used for identifying the strain modes. The relationship between and the degradation degree and the strain mode shapes shows certain rules for the widely used simply supported beam bridges. The numerical simulation proves simple and effective for the proposed method to locate and quantify the stiffness degradation.

• 소음진동
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• 제8권5호
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• pp.799-806
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• 1998

Noise and vibration due to railway traffic are major causes of environmental pollution in the city. In course of judging, assessing and coping with the problem, it becomes imperative to predict the vibration level induced by railway traffic passing through downtown in the city. The vibration due to railway traffic is transferred to the neighbouring buildings through the ground. In this study, as a method predicting vibration level of the buildings near railway, a vibration transfer formula is suggested. This formula is used to calculate vibration level occuring at the bottom of the neighbouring buildings, which are located at a certain distance from railway.

• 한국철도학회논문집
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• 제13권2호
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• pp.208-213
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• 2010

최근 수도권광역급행철도(GTX)사업이 승인됨에 따라, 도심지 터널 내 열차주행에 따른 진동의 영향에 대한 관심이 커지고 있다. 본 논문은 암반층에 건설된 터널 내 열차주행으로 인한 지반진동을 측정하기 위해 실시된 현장측정시험의 과정 및 결과에 대해 기술한다. 약 200km/hr로 주행하는 KTX열차로 인해 발생된 지반의 진동이 터널 인근에 시공된 시추공에 삽입된 3축 시추공 진동 측정장치를 통해 측정되었다. 본 논문은 현재 상용화되어 있는 시추공 진동 측정장치의 한계에 대해서도 논의한다.

• Geomechanics and Engineering
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• 제38권5호
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• pp.497-505
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• 2024

The power plant is a major infrastructure composed of essential machinery such as Turbine Generators (TG), Heat Recovery Steam Generators (HRSG), etc. Particularly, Combined Heat & Power Plants (CHP) are highly efficient power plants that simultaneously produce heat and electricity. Recently, cases have emerged where railway tunnels are being constructed beneath such power plants due to the underground development of urban rail transportation. Therefore, there is a pressing need to assess the impact of vibrations induced by blasting excavation during the construction of railway tunnels beneath the power plant, as well as the vibrations during railway operation, on the major machinery foundations and structures within the power plant. In this study, criteria for evaluating the vibration impact on key vibration-sensitive structures are summarized, and evaluation standards based on international criteria are established. Based on this, the study examines the vibration impact during the blasting excavation method of NATM tunnels beneath the operational power plant. Furthermore, subsequent railway operation, specifically focusing on the impact of train vibrations on Turbine foundations, Pump foundations, and District Heating pipelines using 3D dynamic numerical analysis. The results indicate that vibration values corresponding to up to 97.3% of the evaluation criteria are derived based on the numerical analysis. However, considering the significance of power plant-related structures, additional measures to reduce vibrations are proposed, including further test blasting, alteration of blasting patterns, reducing the charge per delay, or decreasing advance.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.516-521
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• 2005

Recently the railway becomes principal transportation on account of the important role in mass transit and commute in urban area. However, rail noise and vibration raise a major problem for the residents living nearby railway track. At that point of view, the effective counterplan for the soundproofing and protection of vibration has to be considered in the process of railway design. Therefore, the reliable computation of load caused by running train on rail is very important to estimate vibration of structure adjacent to railway. In this study, Input identification is used for the calculation of load and vibration, induced by high speed train on rail. The influence of railroad noise and vibration on structure is evaluated using the 3-D Finite element method and the reliability of the evaluation is discussed comparing with the results of the field measurements.

• Smart Structures and Systems
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• 제17권6호
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• pp.1107-1127
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• 2016

Studies on dynamic characteristics of the hanger vibration using field monitoring data are important for the design and evaluation of high-speed railway truss arch bridges. This paper presents an analysis of the hanger's dynamic displacement responses based on field monitoring of Dashengguan Yangtze River Bridge, which is a high-speed railway truss arch bridge with the longest span throughout the world. The three vibration parameters, i.e., dynamic displacement amplitude, dynamic load factor and vibration amplitude, are selected to investigate the hanger's vibration characteristics in each railway load case including the probability statistical characteristics and coupled vibration characteristics. The influences of carriageway and carriage number on the hanger's vibration characteristics are further investigated. The results indicate that: (1) All the eight railway load cases can be successfully identified according to the relationship of responses from strain sensors and accelerometers in the structural health monitoring system. (2) The hanger's three vibration parameters in each load case in the longitudinal and transverse directions have obvious probabilistic characteristics. However, they fall into different distribution functions. (3) There is good correlation between the hanger's longitudinal/transverse dynamic displacement and the main girder's transverse dynamic displacement in each load case, and their relationships are shown in the hysteresis curves. (4) Influences of the carriageway and carriage number on the hanger's three parameters are different in both longitudinal and transverse directions; while the influence on any of the three parameters presents an obvious statistical trend. The present paper lays a good foundation for the further analysis of train-induced hanger vibration and control.

• 한국철도학회논문집
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• 제12권3호
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• pp.357-363
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• 2009

본 논문에서는 도시철도 운행으로 발생하는 지반진동의 예측을 위하여 서울지하철 현장 계측을 실시하였다. 현장 계측 결과와 뉴욕지하철의 예측식과 동경지하철의 예측식으로 산정된 값과 비교한 결과, 국내 지반의 지반진동레벨은 뉴욕지하철의 예측식보다 크게 산정되었으며, 동경지하철의 예측식보다는 다소 작게 산정되었다. 또한, 계측현장 지반의 전파경로에 따라 토사지반과 암반지반으로 구분하여 국내 지반특성에 적합한 지반진동 예측식을 제안하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.768-769
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• 2009

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1993년도 가을 학술발표회논문집
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• pp.199-204
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• 1993

Noise and vibration induced by subway operation are one of the major factor that annoying residents living near the. railway. In general, lateral vibration was the major concern when we are considering vibration of the building. Since the energy due to earthquake is enormous it affects wide area. However, the vertical vibration became a major concern in considering the vibration induced by subway because relatively smaller energy affects only nearby areas than that of earthquake. Analysis model of the structure for the vertical vibration should consider the effect of beam vibration. Thus, the model of the structure for the lateral vibration can not be applied. Appropriate analysis model which can consider the inertia force of the beam is necessary when analyzing a structure for the vertical vibration. Modeling technique for the vertical vibration analysis of structures has been studied on this paper. It is recommeneded to use 2 or more elements for columns and to use 3 or more elements for beams when analyzing structures for vertical vibration induced by subway.