Spot analysis to determine technical parameters of microblasting cleaning for building materials maintenance

This research examines microblasting cleaning spots on different surfaces to analyse technical parameters for building materials maintenance. Spot and surface tests were made keeping parameters constant to evaluate their influence. Analysis of area field roughness obtained through 3D stereomicroscopy, complemented with macrophotography, portable microscope and spectrophotometry analysis were used to surface evaluation. Results indicate the treated area and alteration are related to distance and mainly blasting angle allowing the selection of microblasting parameters when this technique is needed for building materials maintenance. In addition, results point out the necessity of spot analysis before treatment to define the technical parameters to be used in an actual cleaning. Findings concerning microblasting efficiency and effectiveness, including damage to the substrate and other side effects, are also described.