Location

Chicago, Illinois

Session Start Date

4-29-2013

Session End Date

5-4-2013

Abstract

Case histories have played an important role in guiding development of geotechnical engineering during a time when theory was not sophisticated enough to model even simple problems with an acceptable level of rigor. As the discipline transitions from overwhelming reliance on empiricism to a greater reliance on science, it is useful to reexamine the best known case histories as a general check on modern methods of analysis. In the engineering of foundations in clay, three case histories  the collapses of the Transcona and Fargo grain elevators and the near collapse of the leaning tower of Pisa  stand out. We will see that limit analysis, which is a method of analysis based on two theorems from plasticity theory that allow bounding the collapse load from above and below, produces collapse load estimates that match closely the estimated collapse loads for the two failed grain elevators. It does so without giving the analyst much latitude in selection of input parameters, not requiring the elaborate assumptions needed when attempts are made to use an excessively simplified theory to analyze a real problem. We will also show, using the problem of a leaning tower, how resort to a complete analysis of a boundary-value problem, using a method like the finite element method, is sometimes required in determining the critical ultimate limit state.

Department(s)

Civil, Architectural and Environmental Engineering

Appears In

International Conference on Case Histories in Geotechnical Engineering

Meeting Name

Seventh Conference

Publisher

Missouri University of Science and Technology

Publication Date

4-29-2013

Document Version

Final Version

Rights

© 2013 Missouri University of Science and Technology, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Apr 29th, 12:00 AM May 4th, 12:00 AM

Foundation Failure Case Histories Reexamined Using Modern Geomechanics

Chicago, Illinois

Case histories have played an important role in guiding development of geotechnical engineering during a time when theory was not sophisticated enough to model even simple problems with an acceptable level of rigor. As the discipline transitions from overwhelming reliance on empiricism to a greater reliance on science, it is useful to reexamine the best known case histories as a general check on modern methods of analysis. In the engineering of foundations in clay, three case histories  the collapses of the Transcona and Fargo grain elevators and the near collapse of the leaning tower of Pisa  stand out. We will see that limit analysis, which is a method of analysis based on two theorems from plasticity theory that allow bounding the collapse load from above and below, produces collapse load estimates that match closely the estimated collapse loads for the two failed grain elevators. It does so without giving the analyst much latitude in selection of input parameters, not requiring the elaborate assumptions needed when attempts are made to use an excessively simplified theory to analyze a real problem. We will also show, using the problem of a leaning tower, how resort to a complete analysis of a boundary-value problem, using a method like the finite element method, is sometimes required in determining the critical ultimate limit state.