Reduction in Seismic Ground Shaking with the Use of Soil-Cement Panels

Abstract

Simplified seismic design of a structure in the building code is based on an estimated design spectrum to represent the seismic hazard and the soil amplification potential at a site. General site conditions are used to classify sites in terms of their seismic amplification potential in comparison to rock sites. In this approach site classification is based on the type and shear strength of soils at the site and the average shear wave velocity of the profile. The building code does not provide a direct guidance on the use of soil reinforcement methods in relation to the effect of soil improvement on the seismic amplification potential. Deep soil mixing is one of the ground improvement methods in which in-situ mixed columns or panels are installed to provide foundation support. In this study we investigated the effect of soil mix panel reinforcement on ground motions using a shake table. Natural silty sand (SM) was mixed with various proportions of cement to identify the optimum proportion of cement for soil modification. Annular soil cement panels were prepared with the surface areas of 0.16 and 0.38 square m, respectively. The height of the panels was 0.3m. The panels were cured for 14 days and inserted in a loose sand deposit of 1.2m x 1.2m x 0.6m size. Triaxial accelerometers were set at four different locations to measure the motions within the model, which was shaken with different base motions. The applied motions included a recording from the Northridge Earthquake and a series of sinusoidal waves of different frequencies and amplitudes. The research result shows that the ground acceleration could be reduced by 10% and 31% by introducing the 0.16 and 0.38 square meter panels, respectively.

Meeting Name

2014 Congress on Geo-Characterization and Modeling for Sustainability, Geo-Congress 2014 (2014: Feb. 23-26, Atlanta, GA)

Department(s)

Civil, Architectural and Environmental Engineering

Keywords and Phrases

Building Codes; Reinforcement; Sand; Seismic Design; Seismology; Soil Mechanics; Soils; Sustainable Development; Wave Propagation, Different Frequency; Ground Accelerations; Ground Improvement; Northridge Earthquakes; Shear Wave Velocity; Site Classification; Soil Amplification; Triaxial Accelerometer, Soil Cement

International Standard Book Number (ISBN)

978-078441327-2

International Standard Serial Number (ISSN)

0895-0563

Document Type

Article - Conference proceedings

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2014 American Society of Civil Engineers (ASCE), All rights reserved.

Publication Date

01 Feb 2014

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