Health monitoring and parameter identification of a tied arch bridge under excitation of Wenchuan Earthquake

摘要

China is a nation which is heavily suffering from various types of natural disasters, such as earthquakes and typhoons. This paper presents the health monitoring and parameter identification of a tied arch bridge under excitation of Wenchuan Earthquake, in which has been installed with a long-term structural health monitoring system since November 2007 in Hangzhou. At 14:28 on May 12,2008, Wenchuan Earthquake (Magnitude 8.0) occurred in China's Sichuan Province. The bridge health monitoring system successfully monitored the structural responses due to the earthquake. Abrupt amplitude changes in about 2 minutes are found in the monitoring database starting at 14:37, about 9 minutes later than the earthquake's happening. In order to achieve the on-line alarming of emergent incidents, such as earthquakes and typhoons, we proposed an identification method by comparing the change rate of response data with preset thresholds calculated by the normal response data. Identification of displacement responses under excitation of Wenchuan Earthquake show it is an effective method.