Abstract

A formulation to assess a breakwater damage probability and to select the optimal maintenance strategy is presented and illustrated with a case study in Mexico. The formulation includes the calculation of annual and lifetime exceedance damage probabilities, the cost of damage/failure consequences, epistemic uncertainty and information on port logistics. The limit-state corresponds to the stability of the breakwater core (armour) units and the cost of failure consequences includes the explicit consideration of costs of fatalities, loss of armour units, damage and loss of property to port facilities, and economic loss due to business interruption in the port. The Van der Meer approach is followed to describe the damage state and the number of waves is modelled as lognormal instead of normal. A curve of tetrapod’s weight versus wave height is proposed as an approximation to the tetrapod’s fragility. FOSM (First Order Second Moments) and MCS (Monte Carlo simulation) techniques are implemented. The wave height is identified, through the calculation of gradients, as the most sensitive parameter for epistemic uncertainty. The optimal maintenance is selected after assessing three maintenance alternatives by balancing costs and safety. A breakwater located in Mexico called Tampico Port is used as case study to illustrate the formulation.

摘要

介绍了评估防波堤损坏概率和选择最佳维护策略的公式，并通过墨西哥的案例研究进行了说明。该公式包括计算年度和终生超出损坏概率、损坏/故障后果的成本、认知不确定性和港口物流信息。极限状态对应于防波堤核心（装甲）单元的稳定性，故障后果的成本包括对死亡成本、装甲单元损失、港口设施的损坏和财产损失以及由于以下原因造成的经济损失的明确考虑。港口业务中断。遵循 Van der Meer 方法来描述损坏状态，并且将波数建模为对数正态而不是正态。提出了四足动物重量与波高的曲线作为四足动物脆弱性的近似值。实施了 FOSM（一阶二阶矩）和 MCS（蒙特卡罗模拟）技术。通过计算梯度，波高被确定为认知不确定性最敏感的参数。通过平衡成本和安全性评估三种维护方案后选择最佳维护方案。位于墨西哥的一个名为 Tampico Port 的防波堤被用作案例研究来说明该公式。通过平衡成本和安全性评估三种维护方案后选择最佳维护方案。位于墨西哥的一个名为 Tampico Port 的防波堤被用作案例研究来说明该公式。通过平衡成本和安全性评估三种维护方案后选择最佳维护方案。位于墨西哥的一个名为 Tampico Port 的防波堤被用作案例研究来说明该公式。