Long-Term Mechanical Behavior of Yucca Mountain Tuff and its Variability, Final Technical Report for Task ORD-FY04-021

PDF Version Also Available for Download.

Description

The study of the long term mechanical behavior of Yucca Mountain tuffs is important for several reasons. Long term stability of excavations will affect accessibility (e.g. for inspection purposes), and retrievability. Long term instabilities may induce loading of drip shields and/or emplaced waste, thus affecting drip shield and/or waste package corrosion. Failure of excavations will affect airflow, may affect water flow, and may affect temperature distributions. The long term mechanical behavior of rocks remains an elusive topic, loaded with uncertainties. A variety of approaches have been used to improve the understanding of this complex subject, but it is doubtful that ... continued below

Physical Description

5 Mb

Creation Information

Daemen, Jaak J. K.; Ma, Lumin & Zhao, Guohua March 20, 2006.

Context

This report is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this report can be viewed below.

Who

People and organizations associated with either the creation of this report or its content.

Sponsor

Publisher

  • Nevada System of Higher Education
    Publisher Info: Board of Regents, Nevada System of Higher Education (NSHE), formerly University and Community College of Southern Nevada (UCCSN), on behalf of the University of Nevada, Las Vegas (UNLV)
    Place of Publication: United States

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this report. Follow the links below to find similar items on the Digital Library.

Description

The study of the long term mechanical behavior of Yucca Mountain tuffs is important for several reasons. Long term stability of excavations will affect accessibility (e.g. for inspection purposes), and retrievability. Long term instabilities may induce loading of drip shields and/or emplaced waste, thus affecting drip shield and/or waste package corrosion. Failure of excavations will affect airflow, may affect water flow, and may affect temperature distributions. The long term mechanical behavior of rocks remains an elusive topic, loaded with uncertainties. A variety of approaches have been used to improve the understanding of this complex subject, but it is doubtful that it has reached a stage where firm predictions can be considered feasible. The long term mechanical behavior of "soft" rocks, especially evaporites, and in particular rock salt, has been the subject of numerous investigations (e.g. Cristescu and Hunsche, 1998, Cristescu et al, 2002), and basic approaches towards engineering taking into account the long term behavior of such materials have long been well established (e.g. Dreyer, 1972, 1982). The same is certainly not true of "hard" rocks. While it long has been recognized that the long term strength of ?hard? rocks almost certainly is significantly less than that measured during "short", i.e. standard (ASTM D 2938), ISRM suggested (Bieniawski et al, 1978) and conventionally used test procedures (e.g. Bieniawski, 1970, Wawersik, 1972, Hoek and Brown, 1980, p. 150), what limited approaches have been taken to develop strategies toward determining the long term mechanical behavior of "hard" rock remain in the early research and investigation stage, at best. One early model developed specifically for time dependent analysis of underground "hard" rock structures is the phenomenological model by Kaiser and Morgenstern (1981). Brady and Brown (1985, p. 93) state that over a wide range of strain rates, from 10^-8 to 10^2/s the difference in strength is only a factor of 2, and that "the observed behavior of rock is not significantly influenced by varying the strain rate within the range that is convenient to use in quasi-static laboratory compression tests." While this is undoubtedly true, it does not really address the question as to whether or not strengths thus measured can be considered appropriate for estimating long term strengths. One objective of this investigation was to evaluate the applicability of the approaches by Cruden (e.g. Cruden, 1971, 1974, 1983, 1987) and by Lajtai (e.g. Lajtai and Schmidtke, 1986, 1987) to the prediction of the long term mechanical behavior of the investigated tuffs. This involves in particular static fatigue testing, by conducting uniaxial, triaxial, and indirect splitting (Brazilian) tests over a wide range of strain (or stress, or displacement) rates.

Physical Description

5 Mb

Language

Item Type

Identifier

Unique identifying numbers for this report in the Digital Library or other systems.

  • Report No.: DOE/RW/12232-04-021
  • Grant Number: FC28-04RW12232
  • DOI: 10.2172/878149 | External Link
  • Office of Scientific & Technical Information Report Number: 878149
  • Archival Resource Key: ark:/67531/metadc879585

Collections

This report is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this report?

When

Dates and time periods associated with this report.

Creation Date

  • March 20, 2006

Added to The UNT Digital Library

  • Sept. 21, 2016, 2:29 a.m.

Description Last Updated

  • March 23, 2018, 3:43 p.m.

Usage Statistics

When was this report last used?

Yesterday: 0
Past 30 days: 0
Total Uses: 4

Interact With This Report

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

International Image Interoperability Framework

IIF Logo

We support the IIIF Presentation API

Daemen, Jaak J. K.; Ma, Lumin & Zhao, Guohua. Long-Term Mechanical Behavior of Yucca Mountain Tuff and its Variability, Final Technical Report for Task ORD-FY04-021, report, March 20, 2006; United States. (digital.library.unt.edu/ark:/67531/metadc879585/: accessed October 18, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.