Critical Velocity of High-speed Train Running on Soft Soil and Induced Dynamic Soil Response

Hu, Jing; Bian, Xuecheng; Jiang, Jie

doi:10.1016/j.proeng.2016.06.102

Cited by 27 publications

(15 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to the practical significance of this matter, several efforts [3,4] were made to understand the track responses and determine the optimum running speed of the X-2000 HST at the Ledsgård site using different empirical methods. Remediation was introduced at the site in the form of lime-cement columns to stabilize the ground [5].Subsequent to this case study, several analytical and numerical approaches have been proposed by a number of researchers to assess the critical speed and associated issues [6][7][8][9][10][11][12][13][14].…”

Section: Introductionmentioning

confidence: 99%

Investigation into the critical speed of ballastless track

Bian

et al. 2019

Transportation Geotechnics

Self Cite

View full text Add to dashboard Cite

As train speeds are increased, the issue of the critical speed must be faced, especially when tracks run across soft ground. This is the phenomenon describes the amplification of the track deflections due to coincidence of the train speed with the wavespeeds of the underlying ground. Modern high-speed lines are often constructed on ballastless track which has different dynamic behaviour to conventional ballasted track. Therefore, further research is needed to investigate the critical speed of ballastless track. In this paper, a dynamic analysis model comprising track, embankment and ground is presented based on the two-and-half-dimensional (2.5D) finite element method to predict the vibrations generated by train moving loads. The rails and track slab are modeled as Euler-Bernoulli beams resting on the embankment. The concrete base, embankment and ground are modeled by the 2.5D finite elements. The results show that the critical speed of ballastless track is higher than the Rayleigh wave velocity of the underlying soil and quite close to the Rayleigh wave velocity of the subgrade. The existence of the subgrade can highly improve the critical speed of the ballastless track even with a shallow subgrade of 1.25 m depth. The underlying soil stiffness is the conclusive factor in determining the track vibration amplitude. It is also found that the embankment plays an essential role in reducing the inhomogeneity of the lateral stress distribution and the amplitude of vertical stress in ballastless track.

show abstract

Section: Introductionmentioning

confidence: 99%

Investigation into the critical speed of ballastless track

Bian

et al. 2019

Transportation Geotechnics

Self Cite

View full text Add to dashboard Cite

show abstract

“…e steady-state stress caused by the train load in the foundation was obtained when the train speed was less than the Rayleigh wave speed response answer. Hu et al [22] used the 2.5-dimensional finite element analysis method. e track was simplified to Euler beams, the train load was reduced to single or multiple moving axle loads, the track-embankment-foundation coupling analysis model was established, and the stress of the summarized soil unit body was summarized.…”

Section: Introductionmentioning

confidence: 99%

Calculation and Analysis of Vibration Stress of Guangxi Nanning Subway during Operation

Chang

Luo

Wang

et al. 2022

Advances in Civil Engineering

View full text Add to dashboard Cite

In this study, based on the Mindlin solution in elastic half-space, the stress calculation formula was determined with consideration of any point in the foundation under the dynamic amplification effect. The train load was simplified as a concentrated force moving in the direction of the train, and the stress of the soil under a single wheel load was analyzed. In the state, σz reached a maximum value of 0.56 kPa when the axle was directly above the soil, and the stress decreased until it approached zero as the distance from the soil unit increased. Then, taking the Nanning Metro Line 1 as an example, the load was regarded as the superposition of several single-wheel loads, and the law of the soil stress change at a point directly below the moving line of the train load at different axle loads, speeds, and burial depths was studied. From the analysis of the results, it could be seen that the soil stress under different working conditions was always proportional to the train axle load, speed, and burial depths. The peak stress ratio corresponding to the depths of 9 m, 12 m, and 15 m was 1:2:11, indicating that the closer the load to the soil, the more significantly the stress of the soil element increased. Under multiple wheel loads, the soil stress always exhibited continuous cycle characteristics. The cycle period was related to the time it took for the metro to pass through the point in the soil, and the cycle period was the ratio of the distance between each axle and the vehicle speed.

show abstract

“…For example, the structure of a pedestrian overpass takes up a relatively small pedestrian load, with significant spans, which leads to high slenderness ratio. Also, the pedestrian load itself has a significant dynamic component, which can lead to the occurrence of resonant phenomena [1][2][3][4][5][6]. Accordingly, pedestrian overpasses should provide dynamic pedestrian comfort [7][8][9][10][11][12].…”

Section: Introductionmentioning

confidence: 99%

Trends in the development of composite reinforced concrete structures of pedestrian aboveground overpasses

et al. 2021

View full text Add to dashboard Cite

Pedestrian bridges are an important part of the urban infrastructure that ensures the safety and comfort of pedestrians. They have a number of distinctive features compared to road bridges. Also, the pedestrian load itself has a significant dynamic component, which can lead to the occurrence of resonant phenomena. Composite reinforced concrete bridges are widely used among the road bridges. This is due to the possibility of including the roadway structure in the act, which increases the load-bearing capacity and reliability of the structure. The same advantages are typical for pedestrian aboveground overpasses. However, pedestrian bridges have a number of features that affect the operation of the composite reinforced concrete structure. It is well-known that the difference between bending structures in civil construction and bending structures in bridge and road construction is the ratio of the rigidness of the concrete and steel parts. The load on pedestrian aboveground overpasses is similar to the temporary load in civil buildings, adjusted for a large dynamic component. But at the same time, the spans of pedestrian aboveground overpasses are similar to the spans of road bridges. In this article, the prospects for the development of composite reinforced concrete structures of pedestrian overpasses are reviewed.

show abstract

Critical Velocity of High-speed Train Running on Soft Soil and Induced Dynamic Soil Response

Cited by 27 publications

References 12 publications

Investigation into the critical speed of ballastless track

Investigation into the critical speed of ballastless track

Calculation and Analysis of Vibration Stress of Guangxi Nanning Subway during Operation

Trends in the development of composite reinforced concrete structures of pedestrian aboveground overpasses

Contact Info

Product

Resources

About