Record Details

Equivalent linear stochastic seismic response of isolated bridges

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Equivalent linear stochastic seismic response of isolated bridges
 
Creator JANGID, RS
 
Subject earthquake ground motions
friction pendulum systems
lead-rubber bearings
hysteretic dampers
highway bridges
 
Description Stochastic response of bridges seismically isolated by lead-rubber bearings (LRB) is investigated. The earthquake excitation is modeled as a non-stationary random process (i.e. uniformly modulated broad-band excitation). The stochastic response of isolated bridge is obtained using the time-dependent equivalent linearization technique as the force-deformation behavior of the LRB is highly nonlinear. The non-stationary response of isolated bridge is compared with the corresponding stationary response in order to study the effects of non-stationary characteristics of the earthquake input motion. For a given isolated bridge system and excitation, it was observed that there exists an optimum value of the yield strength of LRB for which the root mean square (rms) absolute acceleration of bridge deck attains the minimum value. The optimum yield strength of LRB is investigated under important parametric variations such as isolation period and damping ratio of the LRB and the frequency content and intensity of earthquake excitation. It is shown that the above parameters have significant effects on the optimum yield strength of LRB. Finally, closed-form expressions for the optimum yield strength of LRB and corresponding response of the isolated bridge system are proposed. These expressions were derived based on the model of bridge with rigid deck and pier condition subjected to stationary white-noise excitation. It was observed that there is a very good comparison between the proposed closed-form expressions and actual optimum parameters and response of the isolated bridge system. These expressions can be used for initial optimal design of seismic isolation system for the bridges. (c) 2007
 
Publisher ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD
 
Date 2011-07-12T20:31:06Z
2011-12-26T13:02:51Z
2011-12-27T05:50:03Z
2011-07-12T20:31:06Z
2011-12-26T13:02:51Z
2011-12-27T05:50:03Z
2008
 
Type Article
 
Identifier JOURNAL OF SOUND AND VIBRATION, 309(3-5), 805-822
0022-460X
http://dx.doi.org/10.1016/j.jsv.2007.07.071
http://dspace.library.iitb.ac.in/xmlui/handle/10054/3572
http://hdl.handle.net/10054/3572
 
Language en