PSI - Issue 37

Rogério Lopes et al. / Procedia Structural Integrity 37 (2022) 123–130 R. F. Lopes et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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involving buses, especially frontal collisions (Cerit et al. 2010), can have disastrous consequences. Currently there is no fully regulations for testing passenger buses subject to frontal impacts, however, in the market there is a targeted regulation for heavy trucks with separated cabin (Cerit et al. 2010). Therefore, an adaption of this regulation is used. As part of the R-29 regulation test, a preliminary study of a subsystem that makes part of the front section of the coach is carried out, specifically the lateral door. Fig. 1 shows the location of the front section to be further studied and the its location on the coach as well as the door location. A simplified structure is used in order to acquire information on how to deal with connections between the different components of the main structure (Yadav and Pradhan 2014).

a) c) Fig. 1. a) Location of the mock-up section of R-29 test b) location of the door in the mock-up section, c) front and back views of the door system According to the regulation, the frontal impact must be carried out using a pendulum with a mass not exceeding 1500 , which will transmit its kinetic energy, on impact ( 55 ) to the entire coach (Europeia 20.11.2010). It was assumed that the door would absorb only about 3% of the total mass. Therefore, on the numerical simulation, a mass, corresponding to 3% of the pendulum mass, weighting 45 , was used. The main pillars of the bus will absorb most of the total impact energy, so only a small fraction is responsible for the door deformation. The present work will intend to validate the experimental data already obtained. Experimentally the door was subjected to a pseudo-dynamic test (De Melo et al. 2001, Melo et al. 2006), which allowed the strain results acquisition along the test time at 6 different locations. The strain measurement was performed perpendicularly to the load. HBM strain gauges, model 1-LY41-3/120 were used and the signals were acquired by a National Instruments module. The displacement field was also acquired using DIC, a technology that uses two high-precision cameras, making it possible to obtain the displacement field of the main panel and to compare the experimental and numerical results (Chen et al. 2018). For the development of this work, two different finite element simulation tools will be used. The main objective will be the comparison of a software suitable for the automotive crash simulation sector, PamCrash (Group June 2019), with Abaqus (Smith 2009), a general finite element software package . A comparison between the numerical and experimental results will be made. 2. Procedure The door subsystem is manufactured of three different raw materials. The tubular structure that constitutes the outer structure and the frame is made of metallic alloy steel S355J2H, while the auxiliary components are made of alloy steel EN 10130 DC01. The main front panel is the only component made of EN AW 5754 H111 aluminium alloy. The mechanical properties corresponding to each material are represented in the Table 1. b)

Table 1. Mechanical properties of the constituting materials

S355J2H = 210 ( ) = 0.29

EN 10130 DC01 = 210 ( ) = 0.29

EN AW 5754 H111 = 70 ( ) = 0.33

Property/Material

Young’s modulus

Poisson’s ratio