Keywords and Phrases
load indentation; rock excavation; Roubidoux sandstone; saturation; specific energy; specific penetration
"The experiment conducted in this research was to determine the behavior of a porous rock under an indenter. To investigate this, medium-grained sandstone was subjected to a series of indentation tests. These tests were conducted under both dry and saturated conditions using a rounded conical indenter. In addition, tests were conducted at different indentation speeds. The test results were used to calculate the mechanical specific energy (SE) and specific penetration (SP). The porewater pressure evolution in the saturated sample was also monitored.
The tests and subsequent analyses reveal that saturation did not affect the specific energy when the indentation rate was 0.3 mm/sec. However, as the indentation rate increased to 20 mm/sec, a 32% decrease in specific energy was observed (significant at 80% confidence). The specific penetration, on the other hand, appeared not be affected by saturation at either indentation speed.
The variability in SE and SP was assumed to be controlled by three factors: saturation, loading rate, and rock properties. The water saturation was expected to be the major factor to affect the overall behavior of the rock beneath the indenter. However, the porewater pressure measurements showed that, though there was a statistically significant pore pressure buildup rate with increasing indentation rate, the maximum pore pressure magnitude was too small to affect the loading pressure. Variability in the rock properties could also cause this variation, but more data are required to separate the rock property effects from saturation and indentation speed effects."--Abstract, page iii.
Gertsch, Leslie S.
Maerz, Norbert H.
Rogers, J. David
Geosciences and Geological and Petroleum Engineering
M.S. in Geological Engineering
Missouri University of Science and Technology
xi, 110 pages
© 2014 Azupuri Ayerikujei Kaba, All rights reserved.
Thesis - Open Access
Rock mechanics -- Research
Electronic OCLC #
Kaba, Azupuri Ayerikujei, "Effects of indentation speed and water saturation level on the behavior of Roubidoux sandstone" (2014). Masters Theses. 7307.