Abstract: In order to improve application of AWJ technology in emergency demolition of post disaster concrete structures, breakage impact of concrete under AWJ was investigated. Firstly, a model of concrete impacted by AWJ was constructed based on coupled SPH and FEM. Then, its impact mechanism on broken concrete with AWJ was explored by changing abrasive particles' diameters, physical properties and abrasive volume fraction. The results indicate that AWJ with a diameter of 0.2 mm causes largest damage to concrete matrix, rupture point of matrix caused by AWJ with a diameter of 0.1 mm is closest to top surface of concrete, and AWJ with a diameter of 0.4 mm tends to cause matrix cracking and accounts for most cracks. It also reveals that garnet abrasive water jet is beneficial to axial propagation of concrete cracks while emery abrasive water jet is beneficial to their radial propagation. Influence of concentration on radial propagation of concrete cracks is as volume fraction of 10% ＞ volume fraction of 20% ＞ volume fraction of 15%, and that on their axial propagation is volume fraction of 20% ＞ volume fraction of 10% ＞ volume fraction of 15%.

Key words: abrasive water jet (AWJ), abrasive parameters, concrete, smoothed particle hydrodynamics (SPH)-finite element method (FEM) coupling, crack propagation