The Study Of Operative Performance Of Railway Steel Truss Bridge Under The Condition Of Large Axle Load Transportation

In the process of operation, railway steel truss bridges are affected by many factors such as the impact of the train and external environment, which will cause problems such as partly damaged or prematurely aging. With the development of Chinese railway heavy haul transport and the increasing of train axle load, the heavy haul train of 30 t axle load has been put into operation, which will lead to disease aggravation. To guarantee the safety of railway operation, the operative performance of existing bridges need to be evaluated. Taking three kinds of bolted and welded through type steel truss bridges of Shuo-Huang Railway as research background, combining finite element model analysis with bridge test, performance of bridge under the condition of large axle load transportation are analyzed. The main work is as follows:(1)Based on finite element model analysis, to summarize the variation of the deflection and member’s stress when bridge under the action of different train load; to compare the difference between the performance of these three bridges in deflection and member’s stress, to evaluate the static performance of the bridges in the condition of 30 t axle load, compared with the condition of standard railway live load.(2)The finite element dynamics models are established, the bridge dynamic performance parameters(dynamic flexibility, dynamic stress, acceleration) under the action of different axle load trains are analyzed specifically. The effect of train axle load and speed on dynamic performance of the bridges; combined with the standard, dynamic performance of the bridges under KM98 train load is evaluated.(3)Combined with bridge test, make clear the operative performance of these three bridges under different load train, and compared with the calculation of the finite element model, to verify the correctness of the conclusion in this paper. To find out the members that the fatigue problem is prominent, based on the calculation of finite element model, fatigue property of the component is analyzed.(4) Integrated model calculation and experiment conclusion, the bridges’ adaptability under the condition of large axle load is evaluated, both the bridges’ safety margin and the damageable parts under the condition of 30 t axle load are clear, to provide theoretical reference for bridge reinforcement.