To study the influence of coral sand particle breakage on its dynamic characteristics, taking the South China Sea coral sand as the research object, one-dimensional consolidation test was conducted to prepare different particle breakage degree samples, and then, the GCTS resonant column test was carried out on these samples. The results show that with the degree of coral sand particle breakage increases, the maximum dynamic shear modulus of coral sand first increases and then decreases, and the minimum damping ratio also shows a similar trend. ...