PSI - Issue 27

Laksmana Widi Prasetya et al. / Procedia Structural Integrity 27 (2020) 125–131 Prasetya et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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that the graph has increased over time. From the curve it appears that the absorbed energy reaches 6662.32 Joules. Based on the existing regulations for this impact attenuator in terms of energy, it has not yet reached 7350 Joules. And from the recorded value of the difference of 683.68 Joules or about 9.3% of 7350 Joules.

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Fig. 3. (a) Crushing force curve; and (b) Internal energy curve.

In addition to the total absorbed energy, the results of kinetic energy are also obtained with maximum energy at 5588.7 Joule with an average at 4305.949 Joule, as shown in Fig. 4a. Based on the outcome, it is seen that at the beginning of the loading for kinetic energy tends to record a constant number, and after reaching 20 s, the curve tends to increase and fluctuate. And the total energy obtained by adding up kinetic energy with absorbed energy which reached 12734.8 Joules with a curve display in Fig. 4b.

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Fig. 4. (a) Kinetic energy curve; and (b) Total energy curve.

3.2. Response to local member Besides displaying the overall results, the following results also show the results of crushing force and internal energy but are divided into two positions, that is, the entire bottom can of 6 and the top of 5. For the crushing force curve at the bottom of the can, the maximum load reaches 280.171 kN. From the curve, it appears at the beginning of the loading curve tends a low load but fluctuating. When compared to the crushing force curve at the position of the top can, the load received tends to have the same average load value. At that time, the can has not been deformed. The bottom cans begin to deform after about 20 s. Seen the curve has a movement that tends not to fluctuate as shown in Fig. 5a. For the crushing force curve at the top can position, the maximum load reaches 500.35 kN. From the curve it