【作者】 蒋学炼；

【导师】 李炎保；

【作者基本信息】 天津大学 ， 港口、海岸及近海工程， 2007， 博士

【摘要】 本论文研究了防波堤风险分析与管理的框架,建立了防波堤工程风险的评估体系及相应模型,解决了技术指标与经济指标及其他非技术指标的结合问题。研究主要侧重于四个方面:①海洋动力因素随机性研究;②防波堤风险量化方法研究;③防波堤风险决策模型研究;④防波堤剩余风险管理研究。在“海洋动力因素随机性研究”部分,首先讨论了极值分布不确定性所带来的防波堤风险。探讨了利用人工神经网络技术推算缺失风浪数据的方法。引进了区域频率分析方法,为解决海洋动力条件极值分布拟合中常见的数据样本匮乏问题提供了一种新的途径。基于一种结构化参数模式,联合统计和物理参数模型建立了海洋动力因素的联合分布,使之更适于概率积分求解和风险分析。在“防波堤风险量化方法研究”部分,基于200多例防波堤事故资料建立了防波堤工程失效树。基于可靠度计算方法提出了防波堤风险量化的手段。考虑到常规可靠度计算方法的缺陷,提出将Monte Carlo法与可靠度计算方法相结合的新思路,使概率计算方法能达到近似全概率的水平。为了验证和探讨风险量化理论在防波堤工程中的实用性和应用方法,给出了基于可靠度的斜坡堤护面块体稳定性分析及基于变形的沉箱式防波堤蛇行破坏模型两个算例。在“防波堤风险决策模型研究”部分,探讨了防波堤工程的决策模型,重点是将效用理论引入防波堤风险决策中,以满足多属性目标决策及风险态度度量的需要。风险分析与管理的一个优势在于能够揭示防波堤生命周期内各阶段的风险,这使得剩余风险的管理成为可能。第四部分“防波堤剩余风险管理研究”重点讨论了防波堤工程剩余风险管理中工程保险费率的厘定。沉箱式防波堤底面与基床之间的摩擦系数是保证其抗滑稳定性的重要随机变量。本文依托相关的工程项目对新型材料-橡胶阻滑板与抛石基床间的摩擦系数进行了试验研究,为本领域提供一些有用的基础资料。更多还原

【Abstract】 In this paper, the risk analysis and management framework of breakwater engineering is studied. The evaluation system and related models are established to integrate the technical indexes with economic indicators or other nontechnical indexes. The work in this paper consists of four parts: study on the randomicity of ocean dynamic elements; research on the quantitative methods for the risks in breakwater engineering; discussion on the decision-making models for breakwater risk; exploring on the management of the remaining risk after the optimization of breakwater.In the first part, the risks of breakwater induced by the uncertainties existing in extremal distribution of ocean dynamic elements are discussed ahead. Then, the Artificial Neural Network technique is introduced to hindcasting the lost wave data in observation. Thereafter, the regional frequency analysis methods based on L-moments is put forward to solve the problem of being short of data samples in the parameter estimate of the extremal distribution by collecting the homogeneous data in neighborhood regions. Risk analysis on breakwater is not possible if the environmental conditions are not properly quantified. It appears that the traditional methods to describe the joint statistics of ocean dynamic conditions are not always consistent with the physical behaviour of wave conditions. An alternative mode is proposed to describe properly the joint probability distribution of ocean dynamic conditions by combining the statistical models with parametric physical models.In the second part, the first produce is the setting up of the fault tree of breakwater by analysing more than 200 cases of breakwater failures. Then, some reliability-based methods are provided for quantifying breakwater risk. A new idea is proposed to improve the precision of computing failure probability by combining Monte Carlo simulation with traditional reliability method. In the end of this part, two case studies, reliability-based stability analysis of rubble mound breakwater and deformation-based model quantifying meandering damage of caisson breakwater, are presented to verifying and discussing the application of risk evaluation theory in breakwater engineering.In the third part, several models for the decision-making of breakwater engineering are discussed. There is a focus on the introduction of the utility theory into this field so as to perform the multi-attribute decision making and measuring the risk attitude of decision maker.Through the risk analysis of breakwater engineering, various risks existing during the lifetime of breakwater could be exposed, which makes the management of remaining risk possible. In the fourth part, the method to determining the premium rate of the insurance of breakwater construction project based on the risk analysis is discussed.The capacity of breakwater against sliding is influenced heavily by the friction coefficient between the bottom of cassion and the rubble mound foundation. It is necessary to have an insight in the random behaviour of the friction coefficient. Based on a project, this paper presents an experimental study on the friction coefficient between rubber slap, a new engineering material against sliding, and the top surface of a rubble mound foundation in the end.更多还原