Evaluating Size Effects for a Porous, Weak, Homogeneous Limestone

Details

• Personal Author:
  Batchler, Timothy ; Chaurasia A ; Diederichs M ; Sinha S ; Walton G
• Description:
  In rock engineering, size effects have been a topic of extensive research since the early 1960s, and despite many advances over the years, our understanding of size effect remains incomplete, especially for weak, porous, homogeneous rocks. Indeed, the vast majority of studies related to size effect have specifically considered low porosity rocks (generally crystalline). To bridge this gap in knowledge, we conducted unconfined compression tests on cubic limestone blocks ranging in size from 0.1 to 0.9 m. Texas Cream Limestone, which is a porous, homogeneous, weak rock, was chosen for this study. As this rock has not previously been studied in the literature, conventional compression tests and indirect tensile strength tests on cylindrical specimens were completed prior to testing the cube specimens. For the largest specimens, 3D digital image correlation (3D-DIC) was employed to track the surficial displacements as a function of the applied load. The tests revealed a lack of size effect for the entire range of block sizes considered. To evaluate size effects more broadly, data from prior studies on sedimentary rocks were compiled, and a tendency for the magnitude of the size effect on strength to decline with increasing porosity was noted. Some hypotheses regarding this trend are presented and evaluated based on strain-field heterogeneity metrics obtained from the 3D-DIC analysis. [Description provided by NIOSH]
• Subjects:
  Mining Occupational Health Safety
• Keywords:
  Author Keywords: Size Effect Compression Tests Digital Image Correlation Geotechnical Engineering Imaging Techniques Limestone Porous Limestone Porous Materials Rock Mechanics Soft Rock Strain Heterogeneity Structural Analysis Tensile Strength

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• Series:
  Mining Publications
• ISSN:
  0723-2632
• Document Type:
  Text
• Funding:
  Contract
• Genre:
  Journal Article
• Place as Subject:
  Arizona ; Colorado ; OSHA Region 3 ; OSHA Region 8 ; OSHA Region 9 ; Pennsylvania
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PMRD - Pittsburgh Mining Research Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  56
• Issue:
  5
• NIOSHTIC Number:
  nn:20066518
• Citation:
  Rock Mech Rock Eng 2023 May; 56(5):3755-3772
• Contact Point Address:
  Sankhaneel Sinha, Colorado School of Mines, Golden, CO, USA
• Email:
  sankhaneelsinha@mines.edu
• Federal Fiscal Year:
  2023
• Performing Organization:
  Colorado School of Mines, Golden
• Peer Reviewed:
  True
• Start Date:
  20160915
• Source Full Name:
  Rock Mechanics and Rock Engineering
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:406aaeb1409934db2b21d2f86159142a35b10225552b38fef3b01e2db71e97b74b37b4d1d700ad196718fa35d7fd4309575797ca036a767a358b3c5539ae7300
• Download URL:
  https://stacks.cdc.gov/view/cdc/215620/cdc_215620_DS1.pdf
• File Type:
  [PDF - 3.29 MB ]