Making Good Use of Structural Health Monitoring Systems: Hong Kong's Experience

Many innovative tall buildings, long span bridges and large space structures emerge in recent years but expose to harsh conditions such as strong winds and severe earthquakes. The installation of long-term comprehensive structural health monitoring systems (SHMS) to important structures becomes a trend to monitor their loading conditions, to assess their performance, to detect their damage, and to guild their maintenance with the utmost goals of ensuring the structures function properly during their long service life and preventing them from catastrophic failure under extreme events. Nevertheless, it is still not clear how to make good use of SHMS toward these goals although SHMS have been installed in some large structures. This paper takes the Tsing Ma Bridge in Hong Kong as an example to manifest how the SHMS installed in the bridge has been utilized since 1997. The SHMS installed in the Tsing Ma Bridge is briefly introduced first. How to use the SHMS for investigating highway loading, railway loading, wind characteristics, and temperature effects is then presented. Identification of time varying natural frequencies and modal damping ratio of the bridge under strong winds in terms of the SHMS is also demonstrated. Toward the performance assessment and damage detection of the bridge, SHMS-based computer simulation and damage assessment are targeted and some typical examples are given. The establishment of SHMS-based bridge rating system for bridge maintenance is commented as an on-going research work. The difficulties encountered and future work needed in this field are finally highlighted for both academic research and practical application.