Long-term monitoring strategy for concrete-based structures using nonlinear Kalman filtering

Abstract
Kalman filtering is introduced as a rational means for developing a monitoring strategy for concrete structures. The mathematics and utility of linear Kalman filters are presented briefly, and the use of linear filters is demonstrated for Fickian diffusion. The nonlinear extended Kalman filter is introduced and its utility in estimating a transport parameter is demonstrated. The concrete service life computer program 4SIGHT is introduced briefly and combined with nonlinear filtering to refine the transport coefficient from a laboratory diffusion experiment. A fictitious monitoring strategy is presented that uses Kalman filtering to both refine estimates and extend the time between monitoring intervals. The advantages of using Kalman filtering, along with the remaining technical difficulties, are discussed.