Centrifuge testing of liquefaction mitigation effectiveness on sand foundations treated with nanoparticles

In the last decade there has been a significant research focus on developing non-disruptive methods to mitigate liquefaction in soil foundations beneath infrastructure. One such method involving the use of nanoparticles has been recently proposed to reduce liquefaction potential without changing the soil skeleton. To explore its effectiveness and mechanisms of anti-liquefaction, an advanced centrifuge test is presented. The test involves a sand model treated with laponite (a clay nanoparticle) which is measured for dynamic responses at appropriate spatial and temporal scales. Following treatment, various pore pressure and acceleration response trends are observed and analyzed. Marked reductions in excess pore pressure, settlement and lateral displacement are evident from the treatment. In combination with laboratory tests, amplitude reduction and trend changes are found to be closely related to the properties of laponite dispersion. Laponite dispersion appears to induce rheological changes in the pore fluid, thus reducing the permeability coefficient and strengthening the restraint of soil particles. This is especially evident in terms of delayed build-up of excess pore pressure. Overall, pore fluid modification using this nanoparticle method shows excellent performance and has potential for future applications in non-disruptive liquefaction mitigation.