PSI - Issue 48

Igor Shardakov et al. / Procedia Structural Integrity 48 (2023) 127–134 Shardakov et al/ StructuralIntegrity Procedia 00 (2023) 000 – 000

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temperatute , С

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Fig. 5. Change in deformation at the base of the supporting column C7 and corresponding temperature changes over 5 days of observation

3.3. Vibrometry unit A special role in the monitoring system is assigned to analysis of dynamic deformation processes. The structure experiences significant vibrations in a wide range of frequencies caused by technological operation. These working loads can be considered as mechanical action with known parameters. The vibrational response of an undamaged structure to these impacts can be considered a reference. The response of the structure at an arbitrary point in time can be compared with this reference response and the change in vibrational properties associated with the occurrence of damage can be assessed. Monitoring system contains 2 groups of vibration sensors - the first includes 8 single component high-frequency accelerometers, and the second - 3 three-component low-frequency seismic sensors (Fig. 2c). The frequency ranges are 0.5-10000 Hz for the first group and 0.3 - 400 Hz. for the second one. Dynamic data is recorded once a day. The start of recording is associated with a certain technological mode (transportation of ore, unloading of ore into a bunker, etc.). Typically, dynamic control unit is in standby mode, data recording is activated at the beginning of the active phase and stops at its end. Fig. 6 shows vibrograms obtained at different stages of the technological cycle. These vibrograms were recorded by high-frequency sensors located in the upper, middle and lower parts of the structure (sensors 1, 5 and 8 respectively).

Fig. 6. Vibrograms obtained at various stages of the technological process.