台风灾害下复杂海域桥址区波高特性研究

Wave Height Characteristics at Bridge Site in the Complex Coastal Area under Typhoon Disasters

台风带来的巨浪对位于复杂海域海洋桥梁的建设和运营构成严重威胁。某在建跨海大桥位于福建沿海台风灾害高发区,桥址区岛屿众多,地形复杂,海洋环境恶劣。为研究复杂海域桥址区的台风期波高特性,现场实测了该海域在台风＂杜鹃＂期间的60h波面数据。通过对实测波面数据进行错误数据和潮位趋势剔除,缺失数据重构等步骤,得到了台风期间实测波高数据。通过对实测波高数据进行线性回归,计算了各个统计波高的比值,并与规范值进行比较。此外,还研究并讨论了适宜于该海域波高的概率分布形式。结果表明：（1）该区域台风期统计波高比值与《港口与航道水文规范》中的相近,但具体到每个小时,具有较强随机性;（2）Gumbel分布与台风期复杂海域桥址区的实测经验波高分布吻合较好。该研究对海洋桥梁设计、施工和极端波浪防灾具有指导意义和参考价值。

Typhoon is one of the common natural disasters in the Southeast coast of China.The huge waves induced by typhoon heavily threaten the construction and operation safety of bridges in the complex coastal area.One sea-crossing bridge under construction is located in the Fujian coastal area,which has a high risk of typhoon disaster,is taken as the example.The bridge site is under harsh marine environment and has many nearby islands and complex terrain.In order to study the characteristics of the extreme waves at the bridge site,60 hours of wave elevation data during Typhoon Dujuan were measured.The wave heights were obtained from the elevation data by,firstly,removing the errors and the trend of the tide and,secondly,reconstructing the missing data.The ratios between different statistic wave heights in this area were calculated by linear regression analysis,and were compared with the values given in＂Code of Hydrology for Harbor and Waterway＂.Probability distributions of the wave height at the site were also discussed.The main conclusions include that,（1）the ratios of the statistic wave heights in this region agree well with those defined in the code.But more specifically,the ratios for each hour＇s result show some randomness.（2）Gumbel distribution is well fit for the observed empirical wave height distribution.The study provides guidance and reference to the design and construction as well as disaster prevention of sea-crossing bridges under extreme waves.