DCIF (Directional Cooling-Induced Fracturing) Westerly Granite AE Borehole Damage Effect Test (Task 3-0)

Description

Directional Cooling-Induced Fracturing (DCIF) experiments were conducted on three rectangular Westerly granite blocks (width=depth=4.0", height=2.0") which were preheated to 200, 400, and 600 degree C to induce damage (microcracks) with varying degrees. Liquid nitrogen was poured in a small, 1"-diameter copper cup attached to the top of the sample, and the resulting acoustic emissions (AEs) and temperature changes on the surface of the sample were monitored. The experiments were conducted under one selected biaxial stress (5.8MPa). The obtained AEs were used to determine the microcracking source locations and amplitude, and the associated moment tensors. The onset time of the AEs was correlated with the cooling temperature, which was used to show that the temperature at the onset of microcracking is not affected significantly by the preexisting damage, compared to the impact of the stress in the sample. Included in this submission are the animations of the AE locations and graphics displaying the measured temperature-AE activity changes for samples with different degrees of microcrack damage.

Resources

Name Format Description Link
10 This document lists the uploaded data file names, explanations for each column of the data tables, and schematic diagrams for the experimental setup and the sensor locations. https://gdr.openei.org/files/1362/DCIF_Task3-0_BoroleDamageTest_Westerly_Metadata.docx
9 Acoustic emission location data for block H. Block H sample used a pre-test heating temperature of 400 C. See the attached meta file for the explanation of the contents https://gdr.openei.org/files/1362/DCIF_Task3-0_location_blockH.dat
47 Thermocouple temperature measurement data for block G. Block G sample used a pre-test heating temperature of 600 C. See the attached meta file for the explanation of the contents https://gdr.openei.org/files/1362/DCIF_Task3-0_blockG_Thermocouple.TXT
0 This animation shows locations of the AE (acoustic emission) events produced within a sample block G, during the local cooling experiment. https://gdr.openei.org/files/1362/DCIF_Task3-0_Westerly_blockG_AEmovie.avi
0 This animation shows locations of the AE (acoustic emission) events produced within a sample block H, during the local cooling experiment. https://gdr.openei.org/files/1362/DCIF_Task3-0_Westerly_blockH_AEmovie.avi
48 Graphical presentation of the identified AE onset temperature as a function of the pre-test heating temperature which induced microcrack damage in the sample https://gdr.openei.org/files/1362/DCIF_Task3-0_PreCrackingTvsOnsetCuCupTemp.TIF
9 Acoustic emission location data for block G. Block G sample used a pre-test heating temperature of 600 C. See the attached meta file for additional explanation of the contents. https://gdr.openei.org/files/1362/DCIF_Task3-0_location_blockG.dat
9 Acoustic emission location data for block I. Block I sample used a pre-test heating temperature of 200 C. See the attached meta file for additional explanation of the contents. https://gdr.openei.org/files/1362/DCIF_Task3-0_location_blockI.dat
48 Graphical presentation of the measured average P-wave velocities in the samples as a function of the applied biaxial stress. Different curves are for samples with different pre-heating temperatures which were used to induce a range of microcrack damage https://gdr.openei.org/files/1362/DCIF_Task3-0_BiaxialStressVsVelocityAllDamagedSamplesAveVelocity.TIF
0 This animation shows locations of the AE (acoustic emission) events produced within a sample block I, during the local cooling experiment. https://gdr.openei.org/files/1362/DCIF_Task3-0_Westerly_blockI_AEmovie.avi
47 Thermocouple temperature measurement data for block H. Block H sample used a pre-test heating temperature of 400 C. See the attached meta file for the explanation of the contents https://gdr.openei.org/files/1362/DCIF_Task3-0_blockH_Thermocouple.txt
48 Graphical presentation of the time vs AE rate and cumulative AE counts https://gdr.openei.org/files/1362/DCIF_Task3-0_Time%20vs%20AE%20rate%20and%20Cumulative%20Count%20summary.tif
47 Thermocouple temperature measurement data for block I. Block I sample used a pre-test heating temperature of 200 C. See the attached meta file for the explanation of the contents https://gdr.openei.org/files/1362/DCIF_Task3-0_blockI_Thermocouple.txt

Tags

  • thermal-fracture
  • dcif
  • processed-data
  • granite
  • test
  • westerly-granite
  • failure-test
  • fracture
  • microcrack
  • biaxial-stress
  • damage-effect-test
  • westerly
  • thermal-stress
  • directional-cooling-induced-fracturing
  • stress
  • borehole-damage-effect
  • raw-data
  • geothermal
  • accoustics
  • acoustic-emission
  • energy

Topics

Categories