Volume 39, Issue 4 (July 2011)
Stress-Strain Behavior and California Bearing Ratio of Artificially Cemented Sand
In this study, effects of cement content and curing time on the compressive stress-strain relationship and California bearing ratio (CBR) value of artificially cemented sand cured up to 7 days was investigated. The CBR study was focused on investigating the sensitivity of this non-destructive test to measure the changes in the compacted cemented sand properties during construction (limited curing time). The cement content in the cemented sand was varied up to 6 % by weight. The strength, modulus, and unit weight of the artificially cemented sand varied from, 60 to 1250 kPa, 14 to 290 MPa, and 15.98 to 18.33 kN/m3, respectively. The CBR values for cemented sand, compacted using the standard proctor method, varied from 8 to 230 %. Compressive stress-strain relationship of cemented sand was represented by a non-linear relationship. Relationship between compressive properties of cemented sand and the CBR was also investigated. The variation of compressive strength, modulus, and CBR values with curing time were represented using hyperbolic relationships. Finite element method (FEM) was used to model the CBR test, based on the data obtained from the unconfined compression tests for 1.5, 3, and 6 % cemented sand. In the FEM analyses the cemented sand was modeled using linear elastic-perfectly plastic constitutive relationship with Mohr-Coulomb failure criteria. The ratio of predicted to measured CBR values varied from 0.67 to 1.31.