الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Due to increasing the constructability capacities, engineers can be able to build higher and higher buildings. Whereas, the challenges race for the sky have not only introduced advanced methods of buildings construction and design, they have also created new problems to face, such as lateral loads induced vibrations. Wind and
seismic loadings are now the source of vibrations in high-rise buildings, which have a direct effect on human’s comfort. Therefore, nowadays, serviceability not strength capacities has become the one of the new primary problems facing engineers when designing high-rise buildings. Several techniques have been developed in order to mitigate the response of tall buildings. One of these techniques is tuned mass damper
(TMD) or tuned liquid damper (TLD) system. In this research, performance of Tuned Liquid Dampers (TLDs) that reduces the displacement and acceleration resulting from wind and earthquake loads in high-rise buildings is studied. Three steel structures models have been designed and fabricated. Each model consists of ten floors with a total height of 1800mm. The models are
tested experimentally under dynamic loading using shaking table. The shaking table with dimensions 1300 x 1700 x 25 mm is connected to an input dynamic loads machine using fixed ramp loading protocol at a frequency of 1.5 Hz and an amplitude
of 2 mm. Simulation of the TLD by a tank with an empty weight 0.5 Kg. Every model
will be tested in two conditions, one with TLD and the other without TLD. The results of accelerations and displacements which measured using accelerometers and linear variable differential transformers (LVDTs) installed at the top roof and the base of the models are recorded. The main objective of the experimental program is to investigate the effectiveness of TLD in reducing structural response against dynamic lateral loads, as the liquid’s sloshing reduces the structure vibration. from the experimental works, it was observed that effectiveness of TLD in reducing structural response against the lateral loads depend on many parameters such as the length of the liquid’s sloshing, aspect ratio of the building and the percentage weight of the TLD to the weight of the structure. For first steel model with plan floor aspect ratio equal to 1/2 and TLD weight equal to 8% of the weight of the structural
model, it was found that there is an enhancement in the performance against lateral load. The displacement and the acceleration are decreased by about 23 % form that for the model without TLD. Similarly, for the second model having plan aspect ratio of 2/3 and TLD with 15% of the weight of the steel structure model there is a decreasing in the displacement and acceleration by about 48%. For the third model with square plan floor and the weight ratio of 11.5% between TLD and the structure model, it was found that the performance of the structure was enhanced by about 18%. Furthermore, the stiffnesses for the tested steel buildings were calculated from the obtained results of the conducted resonance tests. Finally, numerical analyses using ETABS 2018 computer program are done to verify the experimental results for steel structures building with/without TLD.