Location

Chicago, Illinois

Session Start Date

4-29-2013

Session End Date

5-4-2013

Abstract

Field observation and monitoring earth structures is vital to design the structure safely and efficiently. Among different types of instruments, earth pressure cells (EPCs) are used to measure soil pressure in embankment dams, which are not proved to be entirely satisfactory. Presence of cells and installation methods usually affect the accuracy of total stress measurements. Since earth pressure cells are prone to damage by large and sharp stones or by using heavy compaction rollers, one excavates a trench and place EPC within fine grained soil which is compacted with light-weight machines. This nonconformity results in local arching between the installation trench and surrounding fill that transmits stress from flexible zone (installation trench) to surrounding fill. As a result the measured soil stress is less than real one. Moreover, pressure cell underestimates the stress in non homogeneous dams for the reason that transversal arching occurs between the core and shell. In this study numerical analyses were conducted to evaluate the contribution of local and transversal arching in stress underestimation and to further clarify the arching trend in the dam height. According to the obtained results, it is possible to calibrate the registered total stress during construction procedure in an earthfill dam.

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

Effects of Arching on Measurement of Embedded Pressure Cell in Embankment Dam

Chicago, Illinois

Field observation and monitoring earth structures is vital to design the structure safely and efficiently. Among different types of instruments, earth pressure cells (EPCs) are used to measure soil pressure in embankment dams, which are not proved to be entirely satisfactory. Presence of cells and installation methods usually affect the accuracy of total stress measurements. Since earth pressure cells are prone to damage by large and sharp stones or by using heavy compaction rollers, one excavates a trench and place EPC within fine grained soil which is compacted with light-weight machines. This nonconformity results in local arching between the installation trench and surrounding fill that transmits stress from flexible zone (installation trench) to surrounding fill. As a result the measured soil stress is less than real one. Moreover, pressure cell underestimates the stress in non homogeneous dams for the reason that transversal arching occurs between the core and shell. In this study numerical analyses were conducted to evaluate the contribution of local and transversal arching in stress underestimation and to further clarify the arching trend in the dam height. According to the obtained results, it is possible to calibrate the registered total stress during construction procedure in an earthfill dam.