Characterizing long period (1--10 sec) ground motions for base isolated structures located in sedimentary basins

Book · Fri Dec 01 00:00:00 EST 1995

OSTI ID:129030

Graves, R W; Somerville, P G ^[1]

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1. Woodward-Clyde Federal Services, Pasadena, CA (United States)

Many urban regions, including Los Angeles, Portland and Seattle in the United States and Tokyo in Japan, are located above deep sedimentary basins. The conventional approach of estimating ground motions in these environments is to assume that the geology can be characterized by a horizontally stratified medium, and that only the shallowest few tens of meters influence the ground motion characteristics. However, the trapping and amplification of long period (1-10 sec) waves by sedimentary basins can generate amplitudes that are significantly larger than those calculated from simple 1D models of site resonance. This may be of particular concern for base isolated structures which are most sensitive to ground motions in this period range. The recent development of efficient computational methods for modeling seismic wave, propagation in laterally varying geological structure enable the authors to model the effects of sedimentary basins on earthquake generated ground motions. They are now applying this calculation procedure to characterize the ground motions that may be generated in the Puget Trough and the Portland Basin due to large earthquakes on the Cascadia subduction zone, and in the Los Angeles region due to large earthquakes on blind thrust faults beneath the Los Angeles basin.

• OSTI ID: 129030
• Report Number(s): CONF-950740-; ISBN 0-7918-1325-8; TRN: IM9550%%398
• Resource Relation: Conference: Joint American Society of Mechanical Engineers (ASME)/Japan Society of Mechanical Engineers (JSME) pressure vessels and piping conference, Honolulu, HI (United States), 23-27 Jul 1995; Other Information: PBD: 1995; Related Information: Is Part Of Seismic, shock, and vibration isolation 1995. PVP-Volume 319; Mok, G.C. [ed.] [Lawrence Livermore National Lab., CA (United States)]; Chung, H.H. [ed.] [Argonne National Lab., IL (United States)]; Lin, C.W. [ed.] [Lin (Chi-Wen), Martinez, CA (United States)]; Fujita, S. [ed.] [Tokyo Denki Univ. (Japan). Dept. of Mechanical Engineering]; Ishida, K. [ed.] [Central Research Inst. of Electric Power Industry, Chiba (Japan)]; Suzuki, K. [ed.] [Tokyo Metropolitan Univ. (Japan)]; Karim-Panahi, K. [ed.]; PB: 334 p.
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
US WEST COAST
SEDIMENTARY BASINS
ENGINEERING GEOLOGY
SEISMIC WAVES
WAVE PROPAGATION
GROUND MOTION
GEOLOGIC MODELS
SEISMIC EFFECTS
SEISMIC ISOLATION
BUILDINGS
TIME DEPENDENCE
THREE-DIMENSIONAL CALCULATIONS
TWO-DIMENSIONAL CALCULATIONS
FINITE DIFFERENCE METHOD
GEOMORPHOLOGY
EVALUATED DATA