The Effect of Gypsum Cementation on the Mechanical Behavior of Gravely Sands

摘要

The behavior of a cemented gravely sand is studied using triaxial tests. Drained and undrained tests were performed on dry and saturated specimens, and stress-strain characteristics of the soil, along with volumetric and pore pressure changes, were identified. The gypsum plaster was used as the cement agent and was mixed with the soil in different percentages. The tests were done in the usual range of confining pressures, from 25 to 500 kPa. Test results show that dilation occurs even at the highest confining stress and the least cement content. The behavior of the cemented soil is found to be more brittle in drained condition than the undrained one. However, the brittleness of soil decreases with increase in confining stress. The ratio of cemented soil shear strength to the uncemented one decreases as the confining stress increases. The failure envelopes are curved and the drained failure envelopes are above the undrained ones. The friction angle of soil increases slightly with cement content, but the cohesion intercept increase is more noticeable. The principal stress ratio at failure decreases with increase in confining stress.