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As space-based Earth observations are delivering a growing amount and variety of data, the potential of this information to better support disaster risk management is coming into increased scrutiny. Disaster risk management actions are commonly divided into the different steps of the disaster management cycle, which include: prevention, to minimize future losses; preparedness and crisis management, often focused on saving lives; and post-crisis management aiming at re-establishing services supporting human activities. Based on a literature review and examples of studies in the area of coastal, hydro-meteorological and geohazards, this review examines how space-based Earth observations have addressed the needs for information in the area of disaster risk management so far. We show that efforts have essentially focused on hazard assessments or supporting crisis management, whereas a number of needs still remain partly fulfilled for vulnerability and exposure mapping, as well as adaptation planning. A promising way forward to maximize the impact of Earth observations includes multi-risk approaches, which mutualize the collection of time-evolving vulnerability and exposure data across different hazards. Opportunities exist as programmes such as the Copernicus Sentinels are now delivering Earth observations of an unprecedented quality, quantity and repetitiveness, as well as initiatives from the disaster risk science communities such as the development of observatories. We argue that, as a complement to this, more systematic efforts to (1) build capacity and (2) evaluate where space-based Earth observations can support disaster risk management would be useful to maximize its societal benefits.

This paper presents two numerical case studies of medium and strong motion events, namely Loma-Prieta 1989 and Hyogoken-Nambu (Kobe) 1995. These simulations were performed using CyberQuake model. The cyclic elastoplastic constitutive model is fully detailed in the companion paper. Through these case studies, we demonstrate the importance of using appropriate constitutive modelling when the part played by nonlinear phenomena is preponderant. The need to account for 3D kinematics (i.e. the three components of the input motion), is also demonstrated, even though a 1D geometry is considered, as the plastic coupling existing between components of motion during the earthquake, strongly affects the seismic soil response.

International audience; The assessment of historical elements at risk from earthquake loading presents a number of differences from the seismic evaluation of modern structures, for design or retrofitting purposes, which is covered by existing building codes, and for the development of fragility curves, procedures for which have been extensively developed in the past decade. This article briefly discusses: the hazard framework for historical assets, including a consideration of the appropriate return period to be used for such elements at risk; the intensity measures that could be used to describe earthquake shaking for the analysis of historical assets; and available approaches for their assessment. We then discuss various unique aspects of historical assets that mean the characterisation of earthquake loading must be different from that for modern structures. For example, historical buildings are often composed of heterogeneous materials (e.g. old masonry) and they are sometimes located where strong local site effects occur due to: steep topography (e.g. hilltops), basin effects or foundations built on the remains of previous structures. Standard seismic hazard assessment undertaken for modern structures and the majority of sites is generally not appropriate. Within the PERPETUATE project performance-based assessments, using nonlinear static and dynamic analyses for the evaluation of structural response of historical assets, were undertaken. The steps outlined in this article are important for input to these assessments.

This paper, along with its companion paper, presents the importance of the adequate soil behaviour model to simulate earthquake site response analysis. An elastoplastic model taking into account the elementary necessary plastic mechanisms such as progressive friction mobilization, Coulomb type failure, critical state and dilatancy/contractance flow rule, is used. However, one of the obstacles in the use of elastoplastic models in the everyday design processes for evaluation of the seismic soil response is the difficulty in identifying their parameters. In this paper, a methodology to identify a coherent set of parameters of the elastoplastic model for a given type of soil is presented. The strategy behind the decision making process proposed here is based on the use of minimum physical and easily measurable properties of the soil to directly provide or indirectly assess the required model parameters.