Seismic Behavior And Fragility Analysis Of Inverted Cone Water Tower

As a kind of special structure, the water tower is used to supply water, which is of essential for dalily life and industry. In order to achieve its function, the water tower was usually built in residential areas, industrial zones and other personnel relatively dense area. So the seismic performance has a direct impact on the lives and property of the people. To ensure the normal operation of the towers after the earthquake and to minimize earthquake damage to the water tower, an existing reinforced concrete inverted cone water tower was chosen and a series of studies of the water tower is conducted.(1) Water plays an active role in energy dissipation and damping control of the water tower structure under seismic excitations. This paper was to study how the different water storage affected the seismic performance of the RC inverted conical water tank under ground motion and was to explore which is the best water level in shock absorption. Based on the similar principle, a 1/30 scale model of organic glass inverted conical tank model was designed according to a real structure. Through shaking table test, the dynamic characteristics, acceleration and displacement response of the tank model with different water levels in different intensity were obtained. The numerical simulation result, which is obtained by ABAQUS finite element software, is compared with that of the shaking table test.(2) In order to explore seismic vulnerability and weak position of the water tower and provide a reference for design and retrofit of water tower structure, the numerical model of an existing water tower structure is established using finite element software ABAQUS, and 15 ground motions were selected to carry out the incremental dynamic analysis in the cases of one-dimensional, two-dimensional and three-dimensional seismic action. Then the seismic vulnerability curves of the water tower were established and effects caused by different dimensional ground motions on the seismic vulnerability of water tower structure were analyzed. The vulnerable positions of the water tower were explorered.(3) Based on stiffness and deformation criteria,20 ground motions were selected and the collapse vulnerability analysis of the water tower was conducted under the one-dimensional, two-dimensional and three-dimensional seismic action. Seismic collapse fragility curves of the water tower were obtioned. The collapse safety reserve ability of the water tower under different dimentional seimic motions was analysed.