This paper investigates the inherent inaccuracy in the estimation of various extreme response variables (RVs) for different sea defence structures using joint exceedance curve approaches in common use around the UK. Utilising stochastically generated nearshore datasets that include extreme wave and sea-level conditions determined at regular intervals around the English coastline as part of a previous study, and asset information from the Environment Agency's Asset Information Management System database, this paper assesses 592 sea defence structures and their associated extreme response using different joint exceedance curve approaches when compared against the RV approach. This paper highlights that extreme RVs are often underestimated when using a joint exceedance curve approach, which in many cases can be significant. This suggests that the performance of many sea defence structures are incorrectly estimated. As a consequence, joint exceedance curve approaches may under-design sea defence structures to a greater level than previously indicated, or significantly underestimate extreme RVs when assessing the performance of existing structures.

中文翻译：

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研究在海岸工程实践中联合概率曲线的使用

本文研究了在英国各地普遍使用的联合超额曲线法在估计不同海上防御结构的各种极端反应变量（RVs）时固有的不准确性。利用随机生成的近岸数据集（包括先前研究的一部分，在英格兰海岸线周围以固定间隔确定的极端波浪和海平面条件）以及来自环境局资产信息管理系统数据库的资产信息，本文评估了592个海防结构和与RV方法相比，它们使用不同的关节超越曲线方法的相关极端响应。本文强调指出，在使用联合超出曲线方法时，经常会低估极端RV，这在许多情况下可能是重要的。这表明许多海防结构的性能估计不正确。因此，联合超限曲线法可能会将海防结构的设计欠缺到比先前指出的水平更高的水平，或者在评估现有结构的性能时会大大低估极端RV。