Investigating the performance of the tuned liquid dampers with experimental methods

The development of methods that causes structures to be effected less from environmental loadings such as earthquake and wind is an important research field. Tuned liquid dampers are used frequently as passive vibration absorbers to mitigate the vibration of structures. In this work, the performance of tuned liquid dampers to mitigate the structural response is investigated with experimental methods for different cases. Initially, sloshing of water in a tank without any structure is studied. The influence of vibration amplitude and frequency on the magnitude of sloshing force is examined. Additionally, how closeness of sloshing natural frequency and vibration frequency affects the magnitude of sloshing force is also studied. A modular structure the parameters of which (such as natural frequency and mass) can easily be modified is designed. The sloshing vibration absorber is placed on this structure. Experimental data is collected for the base line and cases with sloshing vibration absorber. Mass and natural frequency of structure, sloshing natural frequency of water, input signal type such as earthquake and sinus input, vibration amplitude and frequency and the mass ratio between the structure and the water are changed for these cases and the experimental results are investigated. The results from the experiments show that the sloshing vibration absorbers can be used to mitigate the response of structures for both low and high structures but it is possible to increase their efficiency. Furthermore, an image processing method is developed to detect and track the free surface motion and to calculate the resonantal sloshing force. This method uses only the recorded video of the experiments as input and obtains the free surface motion and resonantal sloshing force with the help of image processing operations. The calculated free surface motion is verified with the ultrasonic sensors and the calculated resonantal sloshing force is also verified with the load cell data.