Rockfall Hazard in an Old Abandoned Aggregate Quarry in the City of Tétouan, Morocco

Abstract

Quarries are places of high instability due to blastings, if left without rehabilitation they become sites of great risk of rockfall, which are the case of the Carian quarry, a small abandoned aggregate quarry, which turned into a slum neighborhood in the north western part of the city of Tétouan, and that has a long history of rockfall incidents since it was shut down in the 60’s. Using rockmass characterization techniques, kinematic study and stability analysis, it was confirmed that many instability mechanisms are found on the walls of the quarry and cause a high risk of rockfall during the rain season, especially that the study area is inhabited. Rockfall trajectory modelling techniques allow the calculation of vertical distribution of rocks falling from the quarry’s walls along different profiles in the area and therefore the determination of a safety perimeter from the quarry wall.