Effect of lateral confinement on wave generation and attenuation induced by granular debris

The lateral confinement effect significantly influences wave amplitude at the generation and propagation stage. A series of physical experiments and numerical simulations considering different parameters was conducted to study the effect of lateral confinement on waves, and the enlargement percentage from lateral confinement on the maximum wave amplitude has been estimated and validated. Results indicate that sliding mass is the most significant factor influencing the wave amplitude on wave generation, with an average influence ratio of 19.0%, and there is a lower influence ratio of 12.3% for particle size parameter. The enlargement percentage induced by lateral confinement decreases from 55.0% to 31.1% on wave generation location as the slide Froude number increases. On the location of wave propagation, the enlargement percentage increases as the slide Froude number increases, ranging from 17.4% to 47.7%. Equations of the enlargement percentage are presented in this study to align the maximum wave amplitude when physical experiments are influenced by lateral confinement.