PSI - Issue 22

S.M. Xie et al. / Procedia Structural Integrity 22 (2019) 353–360 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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4.1 Analysis model and static test verification The length of an aluminum alloy EMU body is 25000mm, the width is 3360mm, the height is 4050mm, and the vehicle capacity is 42.83t. When the finite element model of the vehicle body is established, any structure that contributes to the overall stiffness and local strength of the vehicle is considered, as shown in Figure. 2(a). The finite element model of vehicle body is mainly composed of four-node thin shell elements, and supplemented by three node thin shell elements. The total number of elements is 2467282, the total number of nodes is 2240556, and the weight of the model is 10.456t. The comparison of the larger calculated stresses and the test stress of the main operating conditions 1 (coupler 1500kN compression load combined with AW3 overrider vertical load) and 2 (coupler 1000kN tension load combined with AW3 overrider vertical load combined condition) of the vehicle body ,and the histogram are shown in Figures .2(b) and 2(c). The results of comparative analysis show that the test values of most of the measured points are consistent with the calculated stress distribution, and the maximum error is 13.72%.

a

b c Fig.2. (a) The finite element model of vehicle body; (b) The contrast histogram of condition 1; (c) The contrast histogram of condition 2

4.2 Vehicle body fatigue condition and typical welded joints

According to BS EN12663-1 "Structural requirements of railway vehicle body" standard, the fatigue strength load conditions of the vehicle body are determined, as shown in Table1[8].

Table1 Fatigue load conditions of vehicle body

Acceleration/g

Condition

Remarks

Portrait

Transverse

Vertical 0.15+1 -0.15+1 0.15+1 -0.15+1

1 2 3 4 5 6

— — — —

0.15 0.15 -0.15 -0.15

Vehicle body in stationary state; cycle number

0.15 -0.15

— —

— —

The aluminium alloy EMU body is welded by different shapes of aluminium alloy profiles in accordance with different welding methods, the length of multiple welds is more than 20 meters, and the number of welds of the whole vehicle is more than 300. The typical welded joints of aluminum alloy vehicle body weld is shown in Figure .3.

(a) Lap weld

(b) Butt weld

(c) Fillet weld

Fig.3 .The diagram of typical welded joints of aluminum alloy vehicle body