Water Stabilization Using Microparticles

Abstract

Liquefaction is a phenomenon in which saturated, loose, cohesionless soil loses its strength due to earthquake shaking or some other loading. A major occurrence of liquefaction was observed by engineers in 1964 during earthquakes in Niigata, Japan, and Prince William Sound, Alaska. Both earthquakes produced amazing examples of liquefaction induced damage, including bridge and building collapse. Since these earthquakes, research on liquefaction, its evaluation, and mitigation have been conducted by researchers around the world. However, research in mitigation of liquefaction at post-construction sites has been scarce and options available to engineers to remediate hazards in this situation are lacking. Therefore, this study uses polyacrylamide hydrogel, or just hydrogel, a water absorbing polymer, as a soil additive to mitigate liquefaction on post-construction sites. Testing was conducted on prepared Ottawa sand samples using increasing percentages of hydrogel. Testing included static consolidated undrained triaxial, flex-wall permeameter, uplift pressure, and cyclic mobility. Triaxial testing showed hydrogel had no effect on pore pressure but did reduce sample dilation and strength. Permeability testing produced a reduction in permeability with increasing percent hydrogel. A 0.20 tsf uplift pressure was produced with 0.50% hydrogel. Cyclic mobility testing showed decreased liquefaction susceptibility with increased percent hydrogel.