The study results of the historic narrow-gage railway steel truss bridge built in the last century and still used are provided in this paper. Only one of the spans results is provided herein. Field tests with the original locomotive were carried out in order to develop an analytical model that will be used to evaluate the capacity of the bridge. Responses (dynamic displacements, accelerations, mode shapes, corresponding to the resonance frequencies and modal damping values) for the construction of the bridge were found. Studies have shown that the bridge meets the requirements and has enough reserve to work safely.

Performance of optical table with pneumatic vibration isolators is analyzed within 2–50 Hz frequency range. Specific vibrational excitation platform with a vibrator of the frequency range of 1–50 Hz in one of three directions were tested.The following pneumatic vibration isolator dynamic parameters were identified:transmissibility of vertical oscillation characteristics at 50 Hz frequency range;resonant frequency (vertical direction);damping efficiency at 5 Hz to 10 Hz for excitation frequencies.

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One of the indirect tensile identification methods is the measurement of the structure of the response to the vibration excitation. Then this response is simulated using digital methods. If the similarity to the response structure is achieved, the elasticity parameters can be determined. Using the methodology discussed in this work, the problem of the determination of the elasticity parameters of prints as a consisting of the paper and several layers of inks is solved. The determined parameters of prints will be used for the modeling of the printing process in web printing presses.

In the paper the global optimization problem of truss systems is studied.  The genetic algorithms are employed for the optimization. As the objective function the structure mass is treated; the constraints include equilibrium, local stability and other requirements.  All the truss system characteristics needed for genetic algorithm are obtained via finite element solution. Topology optimization of truss system is performed using original modified genetic algorithm, while the shape optimization – using ordinary genetic algorithm. Numerical solutions are presented. The obtained solutions are compared with global extremes obtained using full search algorithm.  All the numerical examples are solved using original software.