Smartphones provide a great potential to produce structural health monitoring (SHM) systems with citizen-empowered sensor networks. Vibration data produced by ubiquitous sensors can help the authorities to monitor aging urban infrastructure in a rapid, remote, automated, and sustainable fashion. In this study, order to evaluate the feasibility of smartphone accelerometers as SHM instruments, two field test studies are presented. Two pedestrian bridges are monitored with high-quality reference sensors and smartphones. Acceleration time histories and power spectral densities obtained from different smartphone generations are compared with reference sensors. Different vibration levels and sensor positions are considered to represent citizeninduced uncertainties and their influence on identification results. The results show that the smartphone sensors are capable of measuring structural vibrations and identifying modal frequencies. What is more, the accuracy increases as the smartphone generation gets younger. Taking the satisfactory results of these case studies into consideration, the authors are developing an SHM system which integrates a web-based identification platform with citizen participation and smartphone sensors.
doi: 10.12783/SHM2015/21