The scouring and undercutting of pipeline under wave action experience three developing stages: silt stirring stage, current tunnel developing stage, swift undercutting and scouring equilibrium stage.

• 海底管道在波浪作用下冲刷掏空经历了3个演变阶段：泥沙起动阶段、水流隧道发育阶段、快速掏空阶段和冲刷平衡阶段。