in this paper, seismic behavior of the existing buildings equipped by friction dampers is studied. seismic performance of6-story, 9-story and 12-story steel buildings with damper and without damper were studied. the finite element modeling technique (sap2000 software) is used for analysis. time history analyzing was done to achieve this purpose. for nonlinear dynamic analysis, the responses of ...

To date, seismic communication has been demonstrated in a single amphibian, the frog Leptodactylus albilabris. Calling males produce both acoustic and seismic signals simultaneously. The inflating vocal sac not only aids in radiating the call into the air, but also strikes the wet substrate generating vertically polarized Rayleigh waves. These animals are highly sensitive to seismic signals (-1...

Elastomeric bridge bearings have a history of use in the USA of close to 50 years. They are capable of carrying large vertical loads and allowing horizontal movement with low lateral force due to the extreme flexibility of the elastomeric material. They require little maintenance, have no moving parts, have good longevity and are very economical. The elastomer in bridge bearings is usually eith...

The influence of frequency content of seismic excitation on the extent and pattern of pore-water pressure build-up in saturated soil deposits is addressed. Seismic acceleration time histories are generated as uniformly modulated nonstationary stochastic processes, in accordance with prescribed response spectra and prescribed modulating functions. Based on numerical examples, it is shown that th...

Formal extensions of the response spectrum method to include spatial seismic effects are reviewed. Two approaches are described in detail: the first based on random vibrations of a simple oscillator under two-component excitations, and the second analyzing multi-column building seismic response. The subjective choice of these two complementing approaches aims at analyzing the phenomenon of spat...

Fiber optic seismic sensors have been increasingly recognized as promising technologies for many applications, such as intruder detection and perimeter defense systems. Among these, a military seismic sensor is especially challenging because it requires a robust, compact, reliable, easily installable and operated product. This article reports on our recent experimental investigations of a milit...

Several methods for predicting the relationship between the velocity and the liquid-waterto-water-ice ratio in permafrost are derived and examined, including a modification of the Voigt average for three materials based on critical porosity. Field seismic techniques for detecting anomalous velocity or attenuation changes are reviewed in view of the unique wave propagation problems encountered i...

This study, tries to suggest a design method based on displacement using finite difference numerical modeling in reinforcing soil retaining wall with steel strip. In this case, dynamic loading characteristics such as duration, frequency, peak ground acceleration, geometrical characteristics of reinforced soil structure and type of the site are considered to correct the pseudo static method and ...

There are a number of parameters influencing the dynamic and seismic response of bridges. Of these, two important parameters warranting special notice include: the properties of the neoperenes in the state of connection between girders and columns and the shear stiffness of underlying soil in the level of bridge substructure’s connectivity to the ground. In &#10this paper, the effects of these ...

in this paper effect of pile-soil consideration in obtaining seismic response offshore structure is assessed due to earthquake loading. inducedseismic force is one of the most important excitations for the dynamic response of an offshore structure. according to api, seismic forces should be accounted in platform design for seismically active regions in order to determine the allowable seismic r...