Abstract The response of nourished beaches to sea level rise is investigated experimentally with random waves in a laboratory wave flume (20 m × 1 m × 1 m), following on from a previous investigation of the response of non-nourished beaches (Atkinson et al., 2018). The nourishments are placed on beach profiles previously exposed to sufficient durations of waves to have approached a near-equilibrium state, i.e., with stable shoreline, bars and berms. Nourishment was placed in three different locations: on the berm, within the bar trough, and as a shoreline placement. In the latter case, and following Bruun rule concepts (Bruun, 1962), the volume of sediment placed was estimated a priori to lead to zero recession under the chosen water level rise. The nourished beaches were then exposed again to sufficient durations of waves to reach a near-equilibrium state at the raised water level. The shoreline recession and the mean recession of the profile following a rise in water level are compared for both the nourished and non-nourished beaches, and to theoretical estimates based on Bruun rule concepts and a previously developed Profile Translation Model (PTM). Quantitative agreement is found with the variants of the Bruun Rule that account for nourishment and with the PTM, and the predicted recession is within an order of ±30% of the observed recession. Overall, the PTM provides the best estimate of the recession. The mean recession of the profile is found to be in better agreement with the model predictions than the recession measured at the shoreline, because the latter is affected by changes in profile shape around the still water line. The efficacy of the nourishment was investigated from the reduction in the observed recession. The efficacy depends on how the recession is measured. For the mean recession, highest efficacy was observed when all the nourishment is added into the active profile. Conversely, for the shoreline recession, highest efficacy was observed with the nourishment placed on the upper beach because it prevents additional recession through wave overtopping.

中文翻译：

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减轻海平面上升引起的侵蚀的营养选择的实验室调查

摘要 继先前对非营养海滩响应的调查（Atkinson 等人）之后，在实验室波浪水槽（20 m × 1 m × 1 m）中用随机波实验研究了营养海滩对海平面上升的响应。 ., 2018)。营养物被放置在先前暴露于足够持续时间的波浪中以接近平衡状态的海滩剖面上，即具有稳定的海岸线、酒吧和护堤。营养品被放置在三个不同的位置：护堤上、酒吧槽内和海岸线放置。在后一种情况下，并遵循 Bruun 规则概念 (Bruun, 1962)，先验估计放置的沉积物体积，以在选定的水位上升下导致零衰退。然后，滋养的海滩再次暴露在足够长的海浪中，以在升高的水位上达到近乎平衡的状态。对营养海滩和非营养海滩的海岸线衰退和水位上升后剖面的平均衰退进行比较，并与基于布鲁恩规则概念和先前开发的剖面转换模型 (PTM) 的理论估计值进行比较。发现与考虑营养的布鲁恩规则变体和 PTM 的数量一致，并且预测的衰退在观察到的衰退的 ±30% 的范围内。总体而言，PTM 提供了对衰退的最佳估计。发现剖面的平均衰退比在海岸线测量的衰退更符合模型预测，因为后者受静水线周围剖面形状变化的影响。从观察到的衰退的减少来研究营养的功效。有效性取决于如何衡量衰退。对于平均衰退，当所有营养都添加到活动配置文件中时，观察到最高功效。相反，对于海岸线后退，在上海滩上放置的营养物观察到最高功效，因为它可以防止波浪越过造成额外的后退。