Bridge Deformation Monitoring: Insight from InSAR time-series and Finite Element Modeling
Shamshiri, Roghayeh1; Motagh, Mahdi2; Baes, Marzieh2; Sharifi, Mohammad-Ali1

This paper presents the capability of advanced InSAR time-series techniques such as Small Baseline Subset (SBAS) for monitoring of civil engineering structures like bridge.
Deformation monitoring of bridges are essential to mitigate not only the financial and human losses, but also ecological and environmental-related problems. Assessment of deformation during bridge lifespan can provide invaluable insight for better planning and management.

The study area, Lake Urmia causeway in northwest Iran, consists of one bridge and two embankments on both sides of it. The difference between the deformation rate of the embankments on both sides of the bridge may seriously damage the bridge itself, so it is very important to accurately monitor them in space and time in order to assess the state of the bridge concerning deformations.
In this study we apply the InSAR time-series technique of SBAS for 47 SAR images including 10 ALOS, 16 Envisat, 10 ERS2 and 11 TerraSAR-X (TSX) to assess deflation of embankments of Urmia bridge during 2003-2012. The InSAR results are used in a 2D finite element model to assess structural stability of the embankments.