Evaluation of internal actions in tunnel lining applying genetic algorithms to monitoring data

This article presents an algorithm that can be applied to an innovative diagnostic systems for tunnels based on small and low-cost sensors that can be placed inside the tunnel lining and are able to provide the user with real-time information on the state of health of the structure. The aim of the system is measuring the internal actions (axial force, bending moment and shear) and the ovalization of the lining because of the actions exchanged between the ground and the lining itself. The algorithm presented in this paper aims to calculate the forces acting on tunnel lining starting only from the quantities measured by a set of clinometers and pressure sensors placed inside the casting, without any other knowledge of geotechnical or geological parameters. This method can therefore be applied in parallel with other traditional geotechnical investigation tools such as borehole inclinometers and radar interferometry when unexpected actions as landslides are interesting a tunnel.