الفهرس 
CHAPTER (1): INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The current thesis aims to investigate the behavior of elevated water
tanks under earthquake loads. Earthquake load can be considered as the most
dangerous load effect on the water tanks. It causes sloshing of water in the
tank. Sloshing can be defined as the movement of water with large
displacements of an unrestricted free surface, which causes high loads on the
tank walls. This leads to high compressive stresses on tank. Furthermore this
load causes overturning moment at the tank base.
In the current study, two steel elevated tanks are manufactured and
tested to find their dynamic parameters (natural frequencies and mode shapes).
The two tanks are studied in two cases. The first case represents the empty tank
and the second case represents the tank that partially filled with water. The
dynamic parameters of the two tanks are estimated by using the operational modal analysis. This method is new technique used in finding dynamic
properties of the structures. In this method, only response of the tanks was
measured by accelerometers. Impact hammer was used only to excite the tanks
at their bases. Exciting force was not measured. A PULSE Multi-analyzer
System was used to transform the responses of the tanks to laptop by relation
between acceleration and time. Then MATLAP program was used to transform
the response of the tanks from time domain decomposition to frequency.