Abstract

To develop disaster mitigation measures in coastal regions affected by earthquakes, it is important to consider the effects of both seismic and tsunami hazards on road structures and assess the social impacts associated with the economic loss and reduction in network functionality. In this paper, a risk- and resilience-based assessment framework is established for road networks under both seismic and tsunami hazards. In the proposed methodology, the risk and resilience are quantified by the economic loss and postdisaster functionality of road networks, respectively. Uncertainties associated with estimations of fault movement, hazard intensity and structural vulnerability are considered when estimating the failure probability using Monte Carlo simulation. Moreover, structural vulnerability against tsunamis is estimated considering the effects of ground motion-induced damage on the reduction in tsunami capacity. As an illustrative example, the road networks in two Japanese cities expected to be affected by the anticipated Nankai Trough earthquake, which would cause strong ground motions and a subsequent tsunami, are analyzed. Finally, the retrofitting prioritization for various structures is discussed based on the risk and resilience quantified as performance indicators for social impacts.

抽象的

为了制定受地震影响的沿海地区的减灾措施，重要的是要考虑地震和海啸危害对道路结构的影响，并评估与经济损失和网络功能下降相关的社会影响。本文针对地震和海啸灾害下的道路网络，建立了基于风险和弹性的评估框架。在所提出的方法中，风险和应变能力分别通过公路网的经济损失和灾后功能进行量化。使用蒙特卡洛模拟估算故障概率时，会考虑与估算断层运动，危险强度和结构脆弱性相关的不确定性。而且，考虑到地面运动引起的破坏对海啸能力下降的影响，估计了海啸的结构脆弱性。作为示例，分析了预计将受到南海海槽地震影响的日本两个城市的道路网络，这将引起强烈的地面运动和随后的海啸。最后，基于量化为社会影响绩效指标的风险和应变能力，讨论了各种结构的改造优先级。