Search results

Search:
in the keywords: 91.30.Px

Sort By:

Limit search:

Parametric Study of the Seismic Response of Base Isolated Liquid Storage Tanks with Lead-Core Elastomeric Bearings

100%

Yazıcı G.

vol. 125

issue 2

382-384

Field reports from past earthquakes indicate that liquid storage tanks are quite susceptible to earthquake related damages due to the sloshing motion of the contained liquid and that the failure of these structures can have catastrophic impacts on the environment in addition to significant financial losses. Recently, the use of seismic response modification strategies such as base isolation and energy dissipation systems have been extended to liquid storage tanks, particularly large liquified natural gas tanks, in order to protect them from the damaging effects of earthquakes. Base isolation involves the installation of horizontally flexible base isolation bearings under the liquid storage tanks to extend the vibration period of the structure and to provide an additional mechanism for energy dissipation. This paper investigates the effects of the variation of mechanical properties of lead-core elastomeric base isolation bearings on the dynamic response of liquid storage tanks through a comprehensive parametric study which was conducted with a script that uses the Matlab state-space solvers. The paper begins by outlining the mechanical analogue system to be used for calculating the overturning moment and the base shear in tank wall as well as the free surface displacements for a cylindrical liquid storage tank subjected to horizontal base excitation. The nonlinear force-displacement characteristics of the bearings are modelled with the Bouc-Wen hysteresis model. Results of the parametric study show that base isolation can be effective at decreasing the base shear and that special attention must be paid to the increases in the sloshing displacements in determining the freeboard height.

Calculation of Greenland and Antarctica Glaciers' Weights Causing Some Earthquakes and Volcanic Activities

100%

Ürüşan A., Uzel T., Eren K.

vol. 125

issue 2

521-522

Global warming is very important subject for environmental physics. Although the earth seems like inanimate, it acts just like a live mechanism which is called as Glacial-Interglacial Ice. One can consider that there are three periods for this forming, say major (100,000 years), minor (12,000 years) and smaller (1000 years) ice ages. The temperature of the earth is affected by increasing especially CO_2 and other sera gases in the atmosphere. The solar radiation reflected from the earth surface cannot go back to the space due to the sera gases and is absorbed by the atmosphere. After the industrial revolution at the beginning of 20th century, especially in the last 30 years, the amount of CO_2 and the other carbon gases emitted into the atmosphere has been increasing and causing natural disasters like irregular local temperature changes, floods, melting glaciers, and more powerful hurricanes. The solar radiations are mostly reflected by glaciers which are significant formations on the earth. Melting of these glaciers reduces the surface reflection and causes more absorption of solar radiation by the earth. In addition, sea level, amount of fresh water, and perceptible water vapor in the atmosphere may increase. In this study, Greenland and Antarctica glaciers' weights which press the plates downward are calculated. Melting the glaciers, the plates get rid of the pressure and rise upward over the mantle, and may cause some earthquakes, and volcanic activities such as Thoku earthquake in Japan and Eyjafjallajökull and Grimsvötn volcanos in Iceland.

Refine search results

2 Acta Physica Polonica A

2 2014

1 Eren K.

1 Uzel T.

1 Yazıcı G.

1 Ürüşan A.

Search results

Parametric Study of the Seismic Response of Base Isolated Liquid Storage Tanks with Lead-Core Elastomeric Bearings

Calculation of Greenland and Antarctica Glaciers' Weights Causing Some Earthquakes and Volcanic Activities