Research Of The Transmission Coefficient Of Pile Breakwater On The Condition Of Shallow Water Wave

Pile breakwater, a type of breakwater structure is widely adopted in lake protection and beach reclamation, embankment protection engineering and so on, and its mechanics of attenuating wave energy is complex. Study detailedly the influencing factors to attenuate wave energy has important theoretical value and practical value.Based on retrospective study of the previous theories and engineering applications, a physical model of breakwater cross-section under regular wave was carried out, with the parameters varrying from pile space, wave periodand wave height. The model results show that the major factors influencing transmissioncoefficient are the relative gap width 77 and the wave steepness H_i/L (or H_i/gT~2), and the secondary factors is the relative water depth d/Hi (or d/L). an empirical equation was set up on the samples of H_i/L = 0.022-0.066 , η = 0.095-0.548 , minordiameter rigid pile.Based on previous achievements and this experiment, it can be drawn from this study that the minor diameter pile breakwater must be applied with small space only in the area influenced by short period wind wave. To reduce the wave height behind breakwater and resolve the problem of pile uplift in soft clay, it is suggested to use a second row of piles. But the model results also shows that the two rows piles not only is uneconomic but also has no more efficient than that of single row pile breakwater.