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Vehicle excitation by passing over pavement unevenness represents the actual problem which is solved on many departments in this time. The numerical methods are mainly applied for the solutions of the interaction of similar systems. The Finite Element Method (FEM) is the best-known and widely used. It provides appropriate accuracy. In this article, commercial computer software ADINA based on the FEM is used to solve kinematic excitation of vehicle. The 2D model of vehicle which represents real type of lorry T-815 is excited by simulation of passage across obstacle. There are compared dynamic responses of the vehicle on the kinematic excitation at different speeds.

In order to analyse the buckling behaviour of existing bow-string arch bridges, it is necessary to deal with the imperfections that influence the global stability of their superstructures. Direct quantification of the material imperfections represents an extremely difficult task for this type of structure. On the other hand, the geometrical imperfections can be measured in more detail by using special scanners or high-accuracy surveying instruments. This contribution represents a beginning part of the research activities focusing on the real values of geometric imperfections of existing steel arch bridges using three-dimensional (3D) scanning. The possibility of using these data for further theoretical and numerical analysis based on the finite element method (FEM) and for further creating the building information modelling (BIM) of the bridges is proposed. When verifying the stability of bow-string arch bridges, much higher attention has to be paid to the out-of-plane stability of the arches. The numerical models of an existing bridge superstructure were developed to execute a nonlinear analysis with geometrical imperfections included. Both the theoretical and actual imperfections obtained by 3D scanning were taken into account. The obtained data, their comparison and the applicability of the presented method are finally discussed.

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The experimental modal analysis is often used to validate the accuracy of dynamic numerical models. It is also a good tool to obtain valuable information about current condition of the structures that could help to determine residual lifetime. The quality of modal testing results is highly dependent on the proper estimation of the natural frequencies from the frequency response function. This article presents the experimental modal test of the laboratory steel structure in which the natural frequencies and mode shapes are determined.