This paper presents a description of the repair work carried out in 1996 at the Haut-Fond Prince lighthouse structure located in the St. Lawrence River, 8 km (5 mi) from the coast of Tadoussac, Quebec, Canada. The damaged section of the structure in the tidal zone was repaired using dry-mix shotcrete. Due to the particular field conditions (freezing-and-thawing cycles, ice erosion and im-pact, submersion of the repair zones only minutes after the application of shotcrete, etc.), the mixture used contained high early strength cement, silica fume, steel fibers, a liquid air-entraining admixture, and a powdered set-accelerator admixture. Removal of deteriorated concrete, preparation of the surface, replacement of the reinforcement, specifications for the shotcrete produced, as well as the application procedures are described in this article. A certifica-tion session was held to verify the skills of the nozzlemen. Only those qualified were authorized to apply shotcrete on the structure.
This article describes the repair work carried out at the Haut-Fond Prince structure located in the St. Lawrence River at the confluence of the Saguenay and the St. Lawrence rivers, 8 km (5 mi) from the coast of Tadoussac, Quebec, Canada (Fig. 1).