Skip to Main Content
Skip Nav Destination
GEOREF RECORD

An experimental topographic amplification study at Los Alamos National Laboratory using ambient vibrations

Andrew C. Stolte, Brady R. Cox and Richard C. Lee
An experimental topographic amplification study at Los Alamos National Laboratory using ambient vibrations
Bulletin of the Seismological Society of America (March 2017) 107 (3): 1386-1401

Abstract

An experimental study aimed at investigating potential topographic amplification of seismic waves was conducted on a 50-m-tall and 185-m-wide soft-rock ridge located at Los Alamos National Laboratory near Los Alamos, New Mexico. Ten portable broadband seismograph stations were placed in arrays across the ridge and left to record ambient vibration data for approximately 9 hours. Clear evidence of topographic amplification was observed by comparing spectral ratios calculated from ambient noise recordings at the toe, slope, and crest of the instrumented ridge. The inferred resonance frequency of the ridge obtained from the experimental recordings was found to agree well with several simple estimates of the theoretical resonance frequency based on its geometry and stiffness. Results support the feasibility of quantifying the frequency range of topographic amplification solely using ambient vibrations, rather than strong or weak ground motions. Additionally, comparisons have been made between a number of widely used experimental methods for quantifying topographic effects, such as the standard spectral ratio, median reference method, and horizontal-to-vertical spectral ratio. Differences in the amplification and frequency range of topographic effects indicated by these methods highlight the importance of choosing a reference condition that is appropriate for the site-specific conditions and goals associated with an experimental topographic amplification study.


ISSN: 0037-1106
EISSN: 1943-3573
Coden: BSSAAP
Serial Title: Bulletin of the Seismological Society of America
Serial Volume: 107
Serial Issue: 3
Title: An experimental topographic amplification study at Los Alamos National Laboratory using ambient vibrations
Affiliation: University of Texas at Austin, Department of Civil, Architectural and Environmental Engineering, Austin, TX, United States
Pages: 1386-1401
Published: 20170314
Text Language: English
Publisher: Seismological Society of America, Berkeley, CA, United States
References: 45
Accession Number: 2017-037470
Categories: Seismology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus.
N35°45'00" - N35°57'00", W106°25'60" - W106°15'00"
Secondary Affiliation: Los Alamos National Laboratory, USA, United States
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Abstract, Copyright, Seismological Society of America. Reference includes data from GeoScienceWorld, Alexandria, VA, United States
Update Code: 201721
Close Modal

or Create an Account

Close Modal
Close Modal