长大跨桥梁健康监测中的不确定性研究方法

he goal of this paper is to introduce a structural identification (St-Id) approach for long span bridges. A number of strategies for coping with the uncertainties confronted when identifying the dynamic characteristics are also presented. The design and implementation of the field test are first presented to illustrate how uncertainties can be mitigated. Next, data pre-processing strategies including data inspection, time window selection, band-pass filtering, averaging and windowing are proposed to reduce data errors. Three separate post-processing methods, including Peak-Picking, PolyMax, and Complex Mode Indicator Function (CMIF), are executed independently to verify the reliability of the data processing results. Experimental results are correlated with the simulations from its 3D finite element analysis for St-Id. Investigation of a long-span bridge is performed as an example to illustrate how to make structural identification through the procedure including the field test, data processing and FE modal updating.