PHYSICAL AND NUMERICAL MODELING OF DYNAMIC IMPACT ON THE DESIGN

In the field of scientific research, one of the most important is the conduct of experiments. Quite often there is a need to explore different models. To create influences on the object under study that are close in real terms to the real ones, different stands are used. In particular, special platforms are most often used to create a seismic load. However, not all of them meet the requirements imposed on them by researchers. The choice and adaptation of the bench for testing beam reinforced concrete elements of specified sizes for a seismic load is carried out taking into account the possibility of varying the load over a wide range and measuring the acceleration and displacement of the structure. The purpose of the research was modeling of the seismic load on the selected bench and testing the procedure for testing concrete beams for this load, including the development of the construction of the beams and measuring devices. To achieve this goal, the universal dynamic bench was adapted for a specific type of experimental research. In particular, a method has been developed for fixing the structure and measuring instruments under investigation, as well as the method for creating a second half-wave of accelerations. The device for centering the impact site on the working trolley has been developed, which ensures equality of impacts on both pillars of the tested structure. The whole test complex was tested. A control plot of oscillation of a beam structure for a "seismic" type effect is obtained. Mathematical modeling of the beam oscillations on the action of the shock impulse load is carried out using the finite element method. The possibility and expediency of simulating a universal load of the "seismic" type with the help of a universal dynamic stand is substantiated in the work. The design of fastening of a tested element and measuring devices on a working trolley of the stand is offered and applied. A technique for testing experimental designs for a "seismic" type load is proposed and tested. Comparison of the results of numerical simulation with experiment showed satisfactory convergence.

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