Implementation of SHM system for Hangzhou East Railway Station using a wireless sensor network

Abstract

Structural health monitoring (SHM) is facilitated by new technologies that involve wireless sensor networks (WSNs). The main benefits of WSNs are that they are distributed, are inexpensive to install, and manage data effectively via remote control. In this paper, a wireless SHM system for the steel structure of Hangzhou East Railway Station in China is developed, since the state of the structural life cycle is highly complicated and the accompanying internal force redistribution is not known. The monitoring system uses multitype sensors, which include stress, acceleration, wind load, and temperature sensors, as the measurement components for the structural features, construction procedure, and on-site environment. The sensor nodes communicate with each other via a flexible tree-type network. The system that consists of 323 sensors is designed for the structure, and the data acquisition process will continue throughout its whole life cycle. First, a full-scale application of SHM using a WSN is described in details. Then, it focuses on engineering practice and data analysis. The current customized WSN has been demonstrated to have satisfactory durability and strong robustness; hence, it well satisfies the requirements for multi-type sensors to operate in a large area. The data analysis results demonstrate that the effects of the construction process and the environment on the super-large-scale structure have been captured accurately. Those effects include the stress variation throughout the construction process, the dynamic responses that are caused by passing trains, the strain variation caused by temperature change over the long term, and the delay in the wind-pressure history.