This report describes two laboratory tests undertaken to examine the effect of increasing porewater\ud pressure and its relationship to total stress and swelling pressure in KBS-3 specification\ud bentonite. Laboratory data clearly demonstrate that at porewater pressures of 46 MPa the\ud bentonite retains a significant component of its original swelling pressure. Analysis of the total\ud stress data demonstrates significant hysteresis between ascending and descending porewater\ud pressure histories. The amount of hysteresis appears to be linked to the magnitude of the\ud porewater pressure applied to the specimen, suggesting some form of “stress memory” within\ud the clay. By the end of the second test the average swelling pressure had increased from 7.2 MPa\ud to 14.4 MPa, which if correct, has important implications for repository performance assessment.\ud No evidence for classic liquefaction of the clay at high water pressures was observed in this\ud experimental study
To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.