State space representations of damage in reinforced concrete slabs

A promising method to monitor and assess the integrity and strength of RC structures was developed and applied to investigate the load-deformation histories for 1/3rd
-scale slab panels experimentally. The slabs were subjected to point load increments at mid-span to induce damage, and unloaded at intervals to facilitate measurements of dynamic response. The external deflections, internal strains and accelerations were recorded for each load increment, corresponding to a unique damage state. The results from one such test are outlined and presented in this paper. They demonstrate that changes in the dynamic time-domain deformation signatures, viewed using novel visualisation techniques are highly revealing of damage and loss of integrity. Acceleration measurements also reveal the
intermittently chaotic nature of the slab’s
behaviour, and suggest that attractor-based structural health monitoring could be a viable option for such structures. Sufficiently developed, the method could provide model-independent, real-time integrity monitoring and strength assessment of slabs and other RC structures.