Beams on Elastic Foundations: Analysis and Design of Shallow T-Footings on Clays in the San Francisco Bay Area
Publication: Practice Periodical on Structural Design and Construction
Volume 18, Issue 4
Abstract
This paper focuses on the analysis and design of foundations on clayey (elastic) soils in the San Francisco/San Pablo Bay area. Many of these soils have mild to moderate expansive properties that still allow the use of shallow T-footings (strip footings). Although suitable for strip footings, the clayey soils deform under structural loads, causing settlement. This deformation causes internal forces in the reinforced T-footing which need to be properly accounted for in design. Three local methods are examined and compared with respect to their assumptions, conservatism, and appropriateness of use. These methods are the spanability method, the bearing capacity method, and the FEM. Although the spanability and bearing capacity methods are deemed adequate by local building officials and design engineers, this paper recommends the use of a more accurate method for design and analysis such as FEM to properly account for structural loads within the T-footings.
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Information & Authors
Information
Published In
Practice Periodical on Structural Design and Construction
Volume 18 • Issue 4 • November 2013
Pages: 205 - 212
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Nov 23, 2011
Accepted: Oct 16, 2012
Published online: Oct 15, 2013
Published in print: Nov 1, 2013
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