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 ...

The first near-side X-class flare of the Solar Cycle 24 occurred in February 2011 and produced a very strong seismic response in the photosphere. One sunquake was reported by Kosovichev ( Astrophys. J. Lett. 734, L15, 2011), followed by the discovery of a second sunquake by Zharkov, Green, Matthews et al. ( Astrophys. J. Lett. 741, L35, 2011). The flare had a two-ribbon structure and was associ...

A laboratory-scale experimental model has been developed and tested for a system that uses artificially generated high-frequency seismic waves in conjunction with a radar-based noncontact displacement sensor to detect buried landmines. The principle of operation of the system is to measure the transient displacement field very close to a mine location. In this way, the absorption and the geomet...

The effect analysis of strain rate on power transmission tower-line system under seismic excitation is studied in this paper. A three-dimensional finite element model of a transmission tower-line system is created based on a real project. Using theoretical analysis and numerical simulation, incremental dynamic analysis of the power transmission tower-line system is conducted to investigate the ...

In last decades many strategies for seismic vulnerability mitigation of structures have been studied and experimented; in particular energy dissipation by external devices assumes a great importance for the relative simplicity and efficacy. Among all possible approaches the use of fluid viscous dampers are very interesting, because of their velocity-dependent behaviour and relatively low costs....

the main objective of this article is evaluation of the simplified models which have been developed for analysis and design of liquid storage tanks. the empirical formulas of these models for predicting maximum sloshing wave height (mswh) are obtained from mass spring models (msm). a finite element modeling (fem) tool is used for investigating the behavior the some selected liquid storage tanks...

the sirri jacket offshore platform was designed and installed in persian gulf of iran in 1975 and has been in service since that time. the importance of offshore structure's stability and the failure of this kind of structure during an earthquake in different active zones revealed that earthquake loading has to be considered. in this paper, magnetorheological (mr) fluid dampers have been propos...

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...

The behavior and design of four-legged controlled rocking bridge steel truss piers to three components of seismic excitation are presented in this paper. The controlled rocking approach for seismic protection allows a pier to uplift from its base, limiting the force demands placed on the bridge pier and deck, and can allow the structure to remain elastic during an earthquake, preventing damage ...

This paper presents efficient models in the area of damage potential classification of seismic signals. After an earthquake, one of the most important actions that authorities must take is to inspect structures and estimate the degree of damages. The interest is obvious for several reasons such as public safety, economical recourses management and infrastructure. This approach provides a compar...