Effect of post-construction moisture condition on mechanical behaviour of Fiber-reinforced-cemented-sand (FRCS)

ABSTRACT Such parameters as cement content, cement type, relative density, grain size distribution, and moisture condition can influence the mechanical behaviors of Fiber-Reinforced-Cemented-Sand (FRCS). Various tests such as Unconfined Compression Strength (UCS), Unconsolidated-Undrained triaxial compression strength (UU), ultrasonic tests, and various analysis, that is, Scanning Electron Microscopy (SEM), image processing, Analysis of Variance (ANOVA), and sensitivity have been performed to investigate the effect of moisture conditions on the mechanical characteristics of treated sandy soil. All the specimens contained 3% or 6% cement contents by dry weight ratio of soil. In addition, kenaf fibers with 8 mm length were utilized by dry weight ratio of 0, 0.25, 0.5 and 0.75 percent; specimens were cured for 14 and 28 days. The results of unconfined compression test demonstrate that both the peak strengths and the residual strengths were decreased by immersing samples and increasing the saturation degree. For instance, for soaked samples with fiber content (FC) of 0.75%, the UCS and residual strength decreases 28% and 40%, respectively. Additionally, the undrained cohesion (Cu) obtained from unconfined compression test declines due to the sample inundation which is directly related to the amount of fiber. In contrast, triaxial test undrained cohesion (Cu) rises by doing so.