Development of low-cost wireless sensor network and online data repository system for time synchronous monitoring of civil infrastructures

Abstract

Advances in wireless sensor networks (WSN) are well proven and commonly used in Structural Health Monitoring (SHM). SHM using WSN is the modern paradigm which incorporates automated systems for data acquisition, in monitoring, analysis, and identification of structural responses and defects. Even though currently used WSN are economical compared to tethered monitoring systems, it is still unaffordable. The costly nature of traditional data loggers and the low penetration nature of currently used networking protocols, through civil structures thus requiring dense array of sensors, increase the overall cost of a WSN. This paper discusses the development of a low cost WSN to monitor the acceleration response of civil engineering structures using off the shelf products. The developed system is capable of capturing synchronous acceleration response data with the sampling frequency of 100 Hz with a resolution of 0.5 mg. The collected data is processed and shared between peer nodes using sub 1 Gigahertz wireless protocol, and stored within an online based central data repository system replacing traditional data loggers. The developed low cost WSN is proved to be a better low cost alternative in the context of a target building with 48 floors (185 m height).