Fragility analysis using vibration energy harvesters

Abstract

Fragility curves are widely used as indicators of vulnerability of infrastructure to structural/performance demands posed on it by the environment. Fragility of a structure may change due to variety of factors during its lifetime. This renders the applicability of fragility for risk assessment to be reliant on periodically updated estimation. Derivation of fragility requires an estimate of the capacity of the structure and the demand due to external factors. Vibration data can be used as a medium to estimate both capacity and demand on the system. Energy harvesters being self-sufficient vibration sensors are proposed as devices capable of estimating fragility curves in lieu of other inertial sensors. The concept is illustrated here using simplified models. The reduction in system complexity due to the self-powered nature of the energy harvester along with the proposed ability to compute probability of failure make energy harvesters attractive options for monitoring civil infrastructure and thereby minimizes risk at various stages in its lifetime.