An experimental study is presented consisting of swash zone hydrodynamics, sediment transport flux estimates, and bed changes under a single dam-break-driven swash event over a steep (1:7), movable sand bed. The study provides resolved measurements of instantaneous water depths, cross-shore flow velocities, sheet flow and suspended sediment concentrations, and morphological response. An ensemble-averaging over 24 repetitions of the swash event allows convergence in the time-averaged measured swash quantities. The sand bed profile was re-constructed after each run with a re-smoothing procedure that allowed for minimum variations that are within the profiler system accuracy (<0.006 m). High-resolution measurements are employed to reconstruct the spatial-temporal evolution of the flow velocity field. Temporal extrapolation and spatial logarithmic/exponential fits are employed to fill velocity gaps in the measured data for the estimation of instantaneous and depth-integrated sediment flux. The spatial gradients of instantaneous sediment flux indicate that the sheet flow sediment dominates over the suspended load during the most relevant phases for sediment transport. Upon bore arrival and initial uprush, the relative contribution of the sheet flow load is larger than during the backwash phase and is decreasingly dominant onshore. Depth-integrated instantaneous sediment flux and total sediment transport estimates, based on two different approaches, are compared with equivalent total sediment transport estimates obtained from the observed morphological changes and the sediment continuity equation. The close agreement between the various approaches indicates that existing models and empirical estimates for the sheet load concentration profile can be used as first order estimates for sediment transport in the swash zone.

提出了一项实验研究，包括在陡峭 (1:7) 可移动沙床上的单个溃坝驱动的冲流事件下的冲流带流体动力学、沉积物输送通量估计和河床变化。该研究提供了对瞬时水深、跨岸流速、片状流和悬浮泥沙浓度以及形态响应的解析测量。对 24 次斜盘事件重复的整体平均允许时间平均测量斜盘量的收敛。每次运行后都使用重新平滑程序重新构建砂床剖面，该程序允许在剖面仪系统精度 (<0.006 m) 内的最小变化。采用高分辨率测量来重建流速场的时空演变。采用时间外推法和空间对数/指数拟合来填补测量数据中的速度差距，以估计瞬时和深度综合沉积物通量。瞬时泥沙通量的空间梯度表明，在泥沙输移最相关的阶段，板流泥沙在悬浮载荷上占主导地位。在钻孔到达和初始上冲时，片状流载荷的相对贡献大于反冲洗阶段，并且在陆上占主导地位。将基于两种不同方法的深度积分瞬时泥沙通量和总泥沙输移估计值与从观察到的形态变化和泥沙连续性方程获得的等效总泥沙输移估计值进行比较。