Application of GPS for monitoring long-span cable-supported bridges under high winds.

摘要

Many long-span cable-supported bridges have been built across the world in the past two decades to meet the economic, social, and recreational needs of communities. However, due to the highly flexible nature and low damping levels of such bridges, they are vulnerable to wind-induced vibration. To protect the immense capital investments made in such bridges and ensure user comfort and safety during the service stage, the implementation of long-term structural health monitoring systems (SHMS) on long-span cable-supported bridges has become a trend in wind-prone regions. Among all measurement parameters, displacement is a paramount variable used to assess the serviceability, safety and integrity of long-span cable-supported bridges. However, it is difficult to measure the wind-induced absolute displacement of a long-span cable-supported bridge, which includes both a static component and a dynamic fluctuating component, by using traditional sensors. One alternative solution is to use global positioning systems (GPS), but the application of the GPS for bridge monitoring engenders many challenges to professionals. This thesis therefore focuses on the application and integration of global positioning systems (GPS) with structural health monitoring systems (SHMS) and computer simulation to monitor and assess the serviceability and strength of long-span cable-supported bridges under strong winds.