PSI - Issue 73

Veronika Valašková et al. / Procedia Structural Integrity 73 (2025) 155–162 Author name / Structural Integrity Procedia 00 (2025) 000–000

157

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Table 1. Characteristics of spatial vehicle model. Function

Label

Value

Unit

Body mass

22 950

kg kg kg

m 1

Front wheel mass Rear wheel mass

m 2 , m 3 m 4 , m 5

455

1 070

Transversal inertia of the body Longitudinal inertia of the body

62 298 22 950

kg·m kg·m kg·m N/m N/m N/m kg/s kg/s kg/s kg/s

2

I y 1 I x 1

2

Inertia of rear axle Front suspension Rear suspension

I y 4 , I y 5 k 1 , k 2 k 3 , k 4 k 5 , k 6 b 1 , b 2 b 3 , b 4 b 5 , b 6

466

2

143 716.5 N/m

761 256

Stiffness of the front tires Stiffness of the rear tires

1 275 300 2 511 360

k 7 , k 8 , k 9 , k 10

Front damping Rear damping

9 614

130 098.5

Front tire damping Rear tire damping

1 373 2 747

b 7 , b 8 , b 9 , b 10

Full vehicle model of the vehicle is characterized by diagonal mass matrix: [m] D = [ m 1 ; I y 1 ; I x 1 ; m 2 ; m 3 ; m 4 ; I y 4 ; m 5 ; I y 5 ] D = = [ 22950.0; 62298.0; 22950.0; 455; 455; 1070; 466; 1070; 466 ] D [kg, kg·m 2 ].

(1)

and natural frequencies:

[f] = [ f (1) ; f (2) ; f (3) ; f (4) ; f (5) ; f (6) ; f (7) ; f (8) ; f (9) ] = = [ 1.13; 1.29; 1.45; 8.89; 8.89; 10.91; 10.91; 11.71; 11.71 ] [Hz]. (2) The assessment of the accuracy of the spatial calculation model is based on verification of the modal characteristics of the vehicle. A study of the vehicle – pavement interaction involves creating computational model of a vehicle and computational model of a structure – pavement. To obtain relevant results of the numerical simulation, the properties of the computational model must be in agreement with the reality. The parameters of the vehicle model were adjusted with respect to the in-situ experimental output. The modal characteristics of the computational model were compared with modal characteristics of the real vehicle. 2.2. Pavement model FEM computational models of concrete pavements can be created at different qualitative levels. In principle, they can be divided into a single layer and multilayer models. Single layer models are sufficient in case we want to analyze stress and strain states only in the reinforced concrete slab itself and we are not interested in stress and strain states in the individual subgrade layers. If we want to analyze the stress and strain states in the individual substrate layers we need to use multilayer models. In the case of a single-layer model, the slab can be modeled with a shell or with a solid element. The Shell element is more advantageous in case if the outputs are to be the internal forces needed to dimensioning the slab (bending moments, shear forces, torsional moments). The solid element is more advantageous in case if the outputs are to be stress and strain states in the slab. The subject of the modeling, in this case, is a concrete pavement consisting of nine slabs with planar dimensions of 6.8 × 4.9 m and a thickness of 0.24 m located in three rows next to each other. The total dimension of this area is