调查分析了国内外海堤设防标准，把海堤破坏归结为6种模式，并分析风浪与潮位（流）对各种模式的影响，提出风浪与高潮遭遇概率粗略算法；根据海堤结构特点及其破坏模式，提出一种基于风浪与高潮遭遇概率，综合反映结构功能、使用要求与潜在风险，三层次设防的海堤设计标准，在此基础上提供了一种基于风险理论的海堤优化设计方法。

The seawall flood defense criteria both at home and abroad have been investigated and discussed. The failure of seawall is referred to six typical modes and the inferences of the wind wave and tide are analyzed closely on each mode. A rough estimate is suggested for encounter probability of wind/wave with highest tide. A three level criteria for seawall design is proposed, which comprehensively integrates the encounter probability, seawall structure performance and usage requirements and the potential risk. Based on the above-mentioned criteria an optimization design scheme of risk principle for seawall is provided.