Damage and contour quality in rock excavations for quarrying and tunnelling: assessment for properties and solutions for stability

Excavations in rock masses determine the creation of temporary or final exposed surfaces. Features of these surfaces are depending on both geostructural pattern of the rock mass and adopted excavation method: among the others, roughness, quality of the contour and induced damage inside the rock left in place. These aspects are important as they are requirements expected during the excavation and construction procedures, such those involving dam sidewalls, quarry benches, tunnel profile, slope scaling. This methodological paper describes a list of the possible cases, with a particular emphasis on quarrying and tunneling. By following current modes for profile surveying, the damages are reported, in order to obtain suitable indices for induced damage. Finally the proper techniques for excavation are commented on the basis of real case histories of tunnels and quarries in order to reach the primary objectives of damage reduction and stability/productivity goals.