On rehabilitation of hydraulic structures subjected to alkali-aggregate reaction

Over the last few decades, a number of hydraulic structures throughout the world have been experiencing operational and structural problems related to continuing alkali-aggregate reaction. Common remedial measures employed to remedy these problems include post-tensioning and/or concrete slot-cutting. In this paper, the long-term effects of slot-cutting are assessed by means of numerical analysis based on a non-linear continuum theory incorporating chemo-mechanical coupling. The analysis pertains to the junction of the concrete dam and the water intake structure of the Beauharnois power plant situated in Quebec, Canada. Over the last few decades, a number of hydraulic structures throughout the world have been experiencing operational and structural problems related to continuing alkali-aggregate reaction. The remedial measures undertaken in the refurbishing of concrete structures affected by alkali-aggregate reaction (AAR) depend on the level of deterioration of concrete. This chapter focuses on the numerical analysis of some structural elements of the Beauharnois power plant, situated in Quebec, Canada. It examines the long-term effects of slot-cutting at the, junction of the right wing dam and the water intake structure. The numerical simulations are based on a non-linear continuum theory for modelling the mechanical effects of the reaction and employ a contact algorithm for monitoring the progressive closure of the slot.