越浪水体对堤后靠船墩的冲击试验研究

Experimental study on the impact of wave overtopping on the breasting dolphin behind the breakwater

通过三维的波浪物理模型试验,研究了斜坡堤掩护下的靠船墩受力特性,分析不规则波作用下越浪高度和不同波向对靠船墩波浪力的影响规律。试验结果表明:1)当波浪传播到斜坡堤上时,一部分波浪破碎后越过堤顶直接冲击在靠船墩上,另外一部分波浪则会绕过斜坡堤在堤身后方形成绕射波对靠船墩形成冲击。2)由于波浪垂向作用的冲击特性较强,作用在靠船墩上的垂向波浪力要大于正向波浪力和横向波浪力。3)随着越浪高度增大,作用在靠船墩上的垂向波浪力和正向波浪力增大,横向波浪力则没有明显的增大趋势。同时更大的越浪高度也会导致垂向波浪力与横向波浪力的比值增大。4)当越浪高度较小时,波浪正向入射与斜向入射造成的波浪力相差不大;当越浪高度较大时,斜向入射的波浪会引起靠船墩上更大的波浪力,此时波浪的绕射效应也会增强,正向波浪力与横向波浪力的比值会减小。

Based on the three-dimensional wave physical model test, this paper studies the mechanical characteristics of the berthing pier under the cover of the slope dike,and analyzes different influences of wave overtopping height and various wave directions on the wave force acting on the breasting dolphin protected by the rubble breakwater.The results show that: 1) When the wave propagates to the rubble breakwater,some of the wave is breaking and over the breakwater impacting on the breasting dolphin directly,while the other part of the wave will bypass the breakwater and forms the diffracted wave behind the dike to impact on the breasting dolphin.2) Due to the violent vertical wave impact,the vertical wave force acting on the berthing pier is larger than the positive wave force and transverse wave force.3) With the increasing wave overtopping height,the vertical wave force and positive wave force on the breasting dolphin increase significantly,but transverse wave force has no obvious increased trend.Meanwhile,the bigger wave overtopping height will also cause the ratio of vertical wave force to transverse wave force to increase.4) Different from no significant distinguish of wave force between positive wave and oblique wave for small wave overtopping height,oblique wave can produce larger wave load when the wave overtopping height is large.As well,the oblique wave can strengthen the wave diffraction and decreases the rate of positive wave force to the transverse wave force.