Abstract
Two types of consolidation tests using a large consolidometer equipped with Linear Vertical Displacement Trans-ducers (LVDT), pore pressure transducers and total earth pressure cells were carried out. With these instruments, deformation behavior as well as pore pressure responses were monitored throughout the tests. The first type used two-step high pressure loading at 100 and 190 kPa. The second type used incremental step loading starting from an applied pressure of 12 kPa. In the high pressure loading test with 100 and 190 kPa, there was no pore pressure dissipation noted from half a day to more than 10 days, depending on the locations of the pore pressure transducers. However vertical displacement was measured during this period with no pore pressure dissipation. In the low pressure step loading test, the slurry continued to compress without any noticeable dissipation of excess pore pressure. The gain in effective stress was much lower than the applied pressure although large settlement had occurred. The lower bound values of undrained shear strengths measured by laboratory vane and fall cone were in direct proportion to the gain in effective stress. In addition, particle migration was evident from the laboratory measurements.
