large capacity cylindrical tanks are used to store a variety of liquids. their satisfactoryperformance during earthquake is crucial for modern facilities. in present paper, the behavior of cylindricalconcrete tanks under harmonic excitation is studied using the finite element method. liquid sloshing, liquidviscosity and wall flexibility are considered and additionally excitation frequency, liqu...

magnetorheological (mr) dampers have the advantage of being tuned by low voltages. this has attracted many researchers to develop semi-active control of structures in theory and practice. most of the control strategies first obtain the desired forces of dampers without taking their dynamics into consideration and then determine the input voltages according to those forces. as a result, these st...

The simulation of structural and geotechnical systems is a critical step in their design and assessment. The purpose of an earthquake simulation is to estimate the performance of the system under seismic excitation or loads that represent the effects of an earthquake. Structural and geotechnical simulation has a long history of development in earthquake engineering. The computation required to ...

A numerical study that focuses on the maximum displacement response of reinforced concrete structures subjected to earthquake loading is presented. The specific item of the interest is the increase in maximum displacement caused by biaxial base excitation as compared with that for uniaxial base excitation. The maximum displacement of structural systems structures subjected to uniaxial base exci...

In this paper the vibration behaviors of a structure equipped with a tuned liquid column damper (TLCD) under a harmonic type of earthquake loading are studied. However, due to inherent nonlinear liquid damping, it is no doubt that a great deal of computational effort is required to search the optimum parameters of the TLCD, numerically. Therefore by linearization the equation of motion of the s...

The depths and source mechanisms of nine large shallow earthquakes were determined from long-period (150 to 300 s) Rayleigh waves recorded by the Global Digital Seismograph Network (GDSN) and International Deployment of Accelerometers (IDA) networks. We inverted the data set of complex source spectra for a moment tensor (linear) or a double couple (nonlinear). By solving a least squares problem...

In this paper the vibration behaviors of a structure equipped with a tuned liquid column damper (TLCD) under a harmonic type of earthquake loading are studied. However, due to inherent nonlinear liquid damping, it is no doubt that a great deal of computational effort is required to search the optimum parameters of the TLCD, numerically. Therefore by linearization the equation of motion of the s...

in this paper the control algorithm for controlled civil structures subjected to earthquake excitation is thoroughly investigated. the objective of this work is the control of structures by means of the pole placement algorithm, in order to improve their response against earthquake actions. successful application of the algorithm requires judicious placement of the closed-loop eigenvalues from ...

earlier studies have shown conclusively that a tuned liquid damper (tld) is effective for controlling vibrations in structures subjected to narrow-banded wind excitations. a recent numerical study has shown that if the design parameters of a tld are properly set, this device could also be very effective for controlling structural vibration to broad-banded earthquake excitations. here the result...

This study firstly proposes some representative simple methods to obtain the suboptimal passive damping and stiffness parameters from the optimal control gain matrix since it is not possible to add the exact optimal damping and stiffness parameters to the structure in practice. It is shown numerically that modifying the structural damping and the stiffness in the proposed suboptimal ways may su...