Study on Limit Value of Bridge Lateral Rigidity for Preventing Derailment

预防列车脱轨的桥梁横向刚度限值研究

Based on energy random analysis theory for derailment,a new method to analyze the limit value of bridge lateral rigidity for derailment prevention is established.

Based on energy random analysis theory for derailment,a new method for analyzing the limit value of bridge lateral rigidity for derailment prevention is established.

Based on theory of random energy analysis of train derailment,a new method was put forward to establish the limit value of bridge lateral rigidity with which derailment on bridges can be prevented.

On basis of energy random analysis theory for derailment, a new method is presented with which the limit value of bridge lateral rigidity for preventing derailment can be established.

In the paper, the dynamic performances of the speed increase coach are investigated. Compared with the vacant freight vehicles, the derailment factors of coaches are smaller, and the derailment safety is not a dominant factor to rate the lateral stiffness of bridge.

The fundamental problem is also pointed out in stipulating for the limit value of lateral rigidity of continuous steel truss girder bridge in the design criterion for steel structure of railway bridge in China. It is necessary to modify the limit value of lateral rigidity of railway bridge based on the theory of random energy analysis of train derailment on the bridge.

Many derailment cases on bridge show that derailment on bridges cannot be prevented with the existing limit value of steel bridge lateral rigidity. The reason is that the train running safety on bridge cannot be analyzed by means of the existing method for bridge lateral rigidity analysis.

The lateral rigidity limit values determined by the new method can ensure trains to run on bridges with smoothness and comfort,and also can prevent derailment.

(7) The re-research problems are discovered about some limited values of lateral stiffness for bridge stipulated by "Design Prescription for Railway Bridge" and some limited values of lateral vibration amplitude for bridge stipulated by "Test Prescription for Railway Bridge" .

Based on energy random analysis theory for derailment,a new method for analyzing the limit value of bridge lateral rigidity for derailment prevention is established.

Aimed at the two types of high speed railway long span steel bridge-slab truss composite system and arch truss composite system, an analysis of random vibration response of time dependant train bridge system has been made in detail. Taking into account of running safety (expressed as derailment coefficient Q/P <0 88,wheel load variance Δ P/P <0 60), the relation curve between the maximum lateral Sperling comfort criteria Wz.max and the width B of truss are drawn at various speeds of single and double...

Aimed at the two types of high speed railway long span steel bridge-slab truss composite system and arch truss composite system, an analysis of random vibration response of time dependant train bridge system has been made in detail. Taking into account of running safety (expressed as derailment coefficient Q/P <0 88,wheel load variance Δ P/P <0 60), the relation curve between the maximum lateral Sperling comfort criteria Wz.max and the width B of truss are drawn at various speeds of single and double track operations on bridge respectively. In accordance with the allowable lateral Sperling comfort criteria W H z .max 3 0, the width B of truss is determined, which is just the allowable width B of bridge. The transverse stiffness limitation indexes-width span ration of bridge are then obtained. The research achievements obtained in this paper can be referred in the design of high speed railway long span steel bridge.

In the paper, the dynamic performances of the speed increase coach are investigated. Compared with the vacant freight vehicles, the derailment factors of coaches are smaller, and the derailment safety is not a dominant factor to rate the lateral stiffness of bridge. Based on the real bridge testing dada, vehicle bridge dynamic coupling action of the existing steel railway bridges is analyzed. The results show that when the speed increase passenger vehicles pass through a half trough truss bridge or a steel...

In the paper, the dynamic performances of the speed increase coach are investigated. Compared with the vacant freight vehicles, the derailment factors of coaches are smaller, and the derailment safety is not a dominant factor to rate the lateral stiffness of bridge. Based on the real bridge testing dada, vehicle bridge dynamic coupling action of the existing steel railway bridges is analyzed. The results show that when the speed increase passenger vehicles pass through a half trough truss bridge or a steel plate girder bridge at a speed between 140 km·h -1 and 160 km·h -1 , the vehicles have sufficient safety derailment. The vehicles behave in a good riding comfort. The lateral amplitude of the mid span of the bridges increases with the speed of the passing vehicles. However the absolute values of the maximum amplitude are rather small and within the limit proposed in the rating code (1978). The vertical resonance character of a steel plate girder bridge with 32 m in span is also analyzed. The vertical resonance is found not the dominant factor in the vertical stiffness of the bridge, because the resonance does not increase the maximum dynamic deflections in the span. Finally, the phenomenon of the jump point in the lateral amplitude of the steel bridge is analyzed. It is suggested that the CWR rails orjoint frozen rails should be used to avoid the jump point in the lateral amplitude when the vehicles pass through the bridges at a speed over 140 km·h -1 .

Using automatic control theory,mechanical mechanism of derailment of train running on a bridge was discussed.It is found that the derailment results from losing stability of transverse vibration of train-bridge time-variant system.According to the theory of random energy analysis of train derailment on the bridge,a derailment case of freight train running on Youshui Bridge in Jiaoliu line was calculated and analyzed,respectively.The calculated results are corresponded to the real results,and the time history...

Using automatic control theory,mechanical mechanism of derailment of train running on a bridge was discussed.It is found that the derailment results from losing stability of transverse vibration of train-bridge time-variant system.According to the theory of random energy analysis of train derailment on the bridge,a derailment case of freight train running on Youshui Bridge in Jiaoliu line was calculated and analyzed,respectively.The calculated results are corresponded to the real results,and the time history curves of vibration response of the system were obtained when the train derails.Meanwhile,before reinforcing the bridge,the suggested limit value of velocity for preventing train on the bridge from derailment was presented,which is consistent with the limit velocity value obtained by field test.The fundamental problem is also pointed out in stipulating for the limit value of lateral rigidity of continuous steel truss girder bridge in the design criterion for steel structure of railway bridge in China.It is necessary to modify the limit value of lateral rigidity of railway bridge based on the theory of random energy analysis of train derailment on the bridge.