Present study investigating the use of wireless sensor networks (WSNs) in the assessment of bridge condition as well as early warning system. The WSNs are used to measure the acceleration occurred on the bridge and the mode shape of the bridge as the excitation loads passing through the bridge. Fast Fourier Transform (FFT) is applied to transform the measured acceleration to get the frequency of the bridge dynamic response. Numerical integration is applied to determined the acceleration to get the displacement of the bridge dynamic response. Implementing structural dynamics equation, the effective stiffness of the bridge can be determined using the frequency. The effective stiffness and the bridge dynamic response are then used to obtained...