【作者】 付新钰；

【导师】 董胜；

【作者基本信息】 中国海洋大学 ， 港口、海岸及近海工程， 2008， 硕士

【摘要】 我国是一个海洋大国,在绵长的海岸线上修建了保护腹地安全的海堤工程。每年台风引发的风暴潮可能使海堤遭受损坏,由此引发严重的人员伤亡与财产损失。波浪越顶是造成防波堤破坏的重要原因之一,因此,合理确定海堤堤顶高程对于防灾减灾具有十分重要的意义。目前,海堤设计还没有颁布专门的国家标准,但是,沿海省份都有各自的地方标准。这些地方标准采用设计高潮位、波浪爬高与安全超高三者之和来计算堤顶高程,其中设计高潮位采用我国《海港水文规范》推荐的年频率统计法。实际上,用于统计的年极值高潮位往往是由天文潮位与风暴增水组合而成的,而在进行频率分析时,却忽略了两个组成因素的联合作用。同时,地方标准在确定堤顶高程时,对于安全超高值的选取也带有经验性。本文以海堤工程所在地区的长期观测资料为基础,选择适当的波浪爬高公式,运用广义随机空间内的验算点法来确定堤顶高程,为海堤堤顶高程的确定提供一种新的思路。具体计算时,对于不同的随机变量,选择多种极值分布,如Pearson-III型分布、Log-normal分布、Gumbel分布和Weibull分布,进行适线,同时考虑各随机变量间的相关性,建立堤顶高程计算的极限状态方程,估计堤顶高程重现值。以莱州湾某海堤与黄海某海堤为例进行了方法的验证计算。本文主要工作包括以下内容:(1)综述国内外斜坡堤波浪爬高的计算方法,如VDM法、《海港水文规范》方法、《堤防工程设计规范》方法。(2)总结国内外可靠度计算方法,如一次二阶矩法、响应面法、蒙特卡罗法、随机有限元法,并且采用MATLAB软件编写了计算程序。(3)对具体的海堤断面,分别采用地方标准方法和基于可靠性理论的方法确定堤顶高程,计算结果验证了本文方法的可行性和合理性。更多还原

【Abstract】 Along the coastline of China, many sea dikes are constructed to protect the safety of their backlands. The typhoon attacking and associated surge flooding sometimes cause heavy loss of lives and properties. Wave overtopping is one of the main reasons that cause the failure of sea dikes. It is significant to rationally calculate the crest elevation of sea dikes for disaster prevention and mitigation.At present, there is no national code for the design of sea dikes. However, there exist different design criteria in coastal provinces. In these criteria, the sea dike crest elevation is the sum of the design high tide level, wave run-up and the safety free- board. The design high tide level is estimated by annual maxima frequency analysis method recommended by Code for Sea Port Hydrology in China. Actually the annual maximum high tide level used for frequency analysis is combined with astronomical tide level and storm surge elevation. But the joint action caused by there two components is commonly neglected to considered in the frequency analysis of the design high tide level. In the mean time, the safety free-board is given by experience to calculate the crest elevation in local design criteria.On the basis of long term observed data, a novel procedure is presented to compute the sea dike crest elevation with Design Point Method in generalized random space. In this procedure, a proper wave run-up equation is selected and applied through a review of related references. Different extreme value distributions, for example Pearson-III distribution, log-normal distribution, Gumbel distribution and Weibull distribution, are adopted to fit random variables. The sea dike crest elevations corresponding different return periods are estimated by solving the limit state equation. The proposed procedure to calculate the crest elevation of sea dike has been testified by practical examples, such as the dikes built along the banks of both Laizhou Gulf and Huanghai Sea. The main contents of this paper are as follows:(1) To summarize and analyze the domestic and foreign wave run-up formula, such as VDM method, method in Code for Sea Port Hydrology and the method in Code for Hydraulic Dike Design.(2) To summarize and analyze frequently applied reliability methods, such as the first-order second-moment method, response surface method, Monte-Carlo method and random finite element method. The corresponding programs are compiled with MATLAB software.(3) The crest elevations of typical sea dike cross section are separately calculated by the local criteria method and the reliability method. Results show that the presented method is feasible and reasonable to determine the crest elevation.更多还原