Abstract:Abstract: Strain data measured by the structure health monitoring system of the main navigation channel cable-stayed bridge of Donghai Bridge were analyzed. By using Empirical Mode Decomposition (EMD), a one-hour strain response of the middle section of girder was decomposed into an oscillation component (dynamic response) and a trend component (static response). The structural modal frequencies were obtained from the dynamic strain response and simultaneously the traffic flow was estimated based on the static strain response. It can be concluded that the separation between dynamic response and static response of measured strain by EMD is feasible and these two components are of great value in practice.