Shotblasting is a process used to produce a compressive residual stress layer and modify mechanical properties of concrete. It entails impacting a surface with shot (round metallic, glass or ceramic particles) with force sufficient to create plastic deformation. It is similar to sandblasting, except that it operates by the mechanism of plasticity rather than abrasion: each particle functions as a ball-peen hammer. In practice, this means that less material is removed by the process, and less dust created. Shotblast systems utilize high powered vacuums and an air wash system to remove and capture any dust created.
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