NSF Award
8960507
The importance of aseismic design of structures using base isolation techniques is becoming increasingly evident to architects and structural engineers. Many different types of base isolators, generally complex mechanical systems which require an extra floor beneath the building, have been proposed to date. Existing isolation systems are either of a pure-friction or flexible type, or a combination of the two. They reduce earthquake-induced lateral inertial forces on structures through limiting friction effects and/or lengthening the natural period of vibration of the total system. This research project studies a new base isolation system comprised of alternate geosynthetic liners and soil layers. Geomembrane and geotextile geosynthetics typically have very low friction coefficients. A layered geotextile/geomembrane-soil system provides a practical, low-cost, and simple-to- install base isolation system through low frictional properties of geosynthetics and the flexibility of a soil layer. Lateral deflection of structures may be limited by hysteretic damping of the soil layer and by soft backfill materials around the building basement. This research project is Phase I of a Small Business Innovation Research Project.
