Stochastic Seismic Response of an Algiers Site with Random Depth to Bedrock

Journal Article · Fri May 21 00:00:00 EDT 2010 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3452225· OSTI ID:21361978

Badaoui, M; Mebarki, A ^[1]; Berrah, M K ^[2]

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1. Universite Paris-Est, Laboratoire Modelisation et Simulation Multi Echelle, MSME FRE3160 CNRS, 5 bd Descartes, 77454 Marne-la-Vallee (France)
2. Ecole Nationale Polytechnique, 10 avenue Hassan Badi, El-Harrach, Algiers (Algeria)

Among the important effects of the Boumerdes earthquake (Algeria, May 21{sup st} 2003) was that, within the same zone, the destructions in certain parts were more important than in others. This phenomenon is due to site effects which alter the characteristics of seismic motions and cause concentration of damage during earthquakes. Local site effects such as thickness and mechanical properties of soil layers have important effects on the surface ground motions.This paper deals with the effect of the randomness aspect of the depth to bedrock (soil layers heights) which is assumed to be a random variable with lognormal distribution. This distribution is suitable for strictly non-negative random variables with large values of the coefficient of variation. In this case, Monte Carlo simulations are combined with the stiffness matrix method, used herein as a deterministic method, for evaluating the effect of the depth to bedrock uncertainty on the seismic response of a multilayered soil. This study considers a P and SV wave propagation pattern using input accelerations collected at Keddara station, located at 20 km from the epicenter, as it is located directly on the bedrock.A parametric study is conducted do derive the stochastic behavior of the peak ground acceleration and its response spectrum, the transfer function and the amplification factors. It is found that the soil height heterogeneity causes a widening of the frequency content and an increase in the fundamental frequency of the soil profile, indicating that the resonance phenomenon concerns a larger number of structures.

• OSTI ID: 21361978
• Journal Information: AIP Conference Proceedings, Vol. 1233, Issue 1; Conference: 2. international symposium on computational mechanics; 12. international conference on the enhancement and promotion of computational methods in engineering and science, Hong Kong (Hong Kong); Hong Kong (Hong Kong), 30 Nov - 3 Dec 2009; 30 Nov - 3 Dec 2009; Other Information: DOI: 10.1063/1.3452225; (c) 2010 American Institute of Physics; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

97 MATHEMATICAL METHODS AND COMPUTING
ALGEBRA
ALGERIA
AMPLIFICATION
COMPUTERIZED SIMULATION
EARTHQUAKES
FINITE ELEMENT METHOD
GROUND MOTION
MONTE CARLO METHOD
PARAMETRIC ANALYSIS
RANDOMNESS
RESONANCE
SEISMOLOGY
SOILS
STOCHASTIC PROCESSES
TRANSFER FUNCTIONS
WAVE PROPAGATION
AFRICA
ARAB COUNTRIES
CALCULATION METHODS
DEVELOPING COUNTRIES
FUNCTIONS
MATHEMATICAL SOLUTIONS
MATHEMATICS
MOTION
NUMERICAL SOLUTION
SEISMIC EVENTS
SIMULATION