HR: 1340h
AN: S13D-1098    [Abstracts]
TI: Simulation of Earthquake Strong Ground Motion Using the Specific Barrier Model
AU: Halldorsson, B
EM: bh25@eng.buffalo.edu
AF: University at Buffalo, Department of Civil, Structural & Environmental Engineering, Buffalo, NY 14260-4300 United States
AU: Dong, G
EM: gangdong@eng.buffalo.edu
AF: University at Buffalo, Department of Civil, Structural & Environmental Engineering, Buffalo, NY 14260-4300 United States
AU: Mavroeidis, G
EM: gm25@eng.buffalo.edu
AF: University at Buffalo, Department of Civil, Structural & Environmental Engineering, Buffalo, NY 14260-4300 United States
AU: Zhang, F
EM: fzhang@eng.buffalo.edu
AF: University at Buffalo, Department of Civil, Structural & Environmental Engineering, Buffalo, NY 14260-4300 United States
AU: * Papageorgiou, A
EM: papaga@eng.buffalo.edu
AF: University at Buffalo, Department of Civil, Structural & Environmental Engineering, Buffalo, NY 14260-4300 United States
AB: There are two key fault parameters that represent length scales and control the intermediate and high frequency content of near-fault ground motion: (1) the barrier interval; and, (2) the length of the cohesive end-zone at the crack tip. The barrier interval controls the rise time and therefore is related to the pulse duration of the near-fault pulses that carry considerable destructive potential for man-made structures. On the other hand, the length of the cohesive end-zone at the crack tip, which is a measure of the effective thickness of the fault gauge, is expected to control the intensity of the radiated near-fault pulses. In the present work we focus on the barrier interval, which is equal to the size of the representative sub-event of a main event. The barrier interval is equal to the diameter of the circular cracks of the equal-size sub-events that compose the main event in the Specific Barrier Model (SBM) proposed by Papageorgiou and Aki (1983). We have recently calibrated the model using the most up-to-date databases of earthquake events representing three tectonic regimes (Halldorsson and Papageorgiou, 2004). Using the parameters of the SBM that were obtained from the above calibration, we proceed to simulate time histories for a number of earthquake events that were well recorded, cover a wide magnitude range (Mw 5.9 - 7.9), and are representative samples of different source mechanisms. Objective measures are used to assess the quality of fit of the simulated time histories to the recorded motions. A key assumption of the SBM is the uniform distribution of the seismic moment released over the fault plane (i.e., all sub-events are of equal size). We assess the bias (if any) introduced to the overall simulation by the above assumption. The overall goal of the exercise is to assess the effectiveness of the SBM to provide time histories of earthquake ground motion that can be used with confidence by earthquake engineers in aseismic design.
DE: 7260 Theory and modeling
DE: 7212 Earthquake ground motions and engineering
DE: 7215 Earthquake parameters
SC: Seismology [S]
MN: 2004 AGU Fall Meeting