Erosion is defined in this report as the progressive dis-integration of a solid by cavitation, abrasion, or chemicalaction. This report is concerned with: 1) cavitation ero-sion resulting from the collapse of vapor bubbles formedby pressure changes within a high-velocity water flow; 2)abrasion erosion of concrete in hydraulic structurescaused by water-transported silt, sand, gravel, ice, ordebris; and 3) disintegration of the concrete in hydraulicstructures by chemical attack.
Other types of concretedeterioration are outside the scope of this report.Ordinarily, concrete in properly designed, constructed,used, and maintained hydraulic structures will undergoyears of erosion-free service. However, for a variety ofreasons including inadequate design or construction, oroperational and environmental changes, erosion does oc-cur in hydraulic structures.
This report deals with threemajor aspects of such concrete erosion:Part 1 discusses the three major causes of concrete erosion in hydraulic structures: cavitation, abrasion, andchemical attack.