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This report details the procedures that have been applied, developed or improved in Task 4.5 for the rapid estimation of damages and losses after an earthquake event. The report revolves around several actions and technical results, which are organized as follows: • Section 3 summarizes the state-of-the-art of current rapid response algorithms and systems, based on a review by Guérin-Marthe et al. (2021). The SELENA and Armargedom software, coupled with shake-map estimates from WP3, are put forward as one of the technical solutions to be implemented in the TURNkey platform. • Section 4 conducts a benchmark study of two damage estimation methods, namely SELENA (Molina et al., 2010), using fragility functions, and Armagedom (Sedan et al., 2013), using semi-empirical vulnerability indices. Both methods are applied on two case-study areas (Luchon area in TB-2 and Alicante area) and the damage distributions are compared. • Section 5 investigates the impact of various factors (resolution of soil amplification maps and building exposure datasets, influence of ground-motion variability) on the accuracy of the damage estimates when applying earthquake scenarios over built areas. Two case studies are considered, namely the Luchon area (TB-2) and the town of Hveragerði (TB3). • Section 6 introduces a probabilistic framework for near real-time seismic damage assessment that exploits heterogeneous sources of information about the seismic input and the structural response to the earthquake. The value of information provided by various combinations of observations and measurements is quantified. The approach is applied to an arbitrary roadway bridge near Patras (TB-4). • Section 7 introduces a sampling-based Bayesian updating method in order to refine damage and loss estimates from field observations. The method is applicable to large real-world systems, such as extended built areas or real-world infrastructure systems. It is applied to the Luchon area (TB-2), where the damage distribution of common buildings and the connectivity loss of the road network system are estimated in a rapid response context. The Bayesian approach for the updating of damage and loss estimated has been implemented in a R/Matlab code, which is briefly described in the companion Deliverable D4.9.

On November 26, 2019, a magnitude Mw = 6.4 earthquake struck Northwestern Albania. It was the strongest to hit Albania in more than 40 years. Cities such as Thumanë, Tirana, and Durrës suffered damage, but Durrës was the hardest hit with several building collapsed [1, 2]. A reconnaissance team under the auspices of American Concrete Institute (ACI) visited Durrës, Albania to assess the extent of damage to modern reinforced concrete (RC) buildings (i.e. built after 1990). The team*1 surveyed buildings during the week of January 12, 2020, with a focus on RC buildings that were infilled with clay block masonry. Over the course of seven days the team documented 55 buildings that had RC frames as their main lateral resisting system. All of the surveyed buildings had unreinforced masonry infills (hollow clay blocks). Most of the buildings had ribbed or waffle slabs. Typical damage observed in these buildings was in- plane or out-of-plane failure (dominant) of masonry infill walls throughout the building height. More damage was observed when these masonry walls were not confined well within the RC frame i.e. acting as partitions. In many cases, these masonry walls were not connected to the RC frame at all, having only bed- joints filled with mortar. This report focuses on the performance of masonry components (infill walls, partitions, etc.) in the buildings in Durrës that were affected by the earthquake. Examples of the damage to the masonry infill, structural details that affected the damage, and its impact on building performance are described. The paper provides an overview of the earthquake- induced damages in several building types and their variation within different structural systems focusing on RC frames with unreinforced masonry infills in Durrës. Reasons for significant differences in observed damage will be discussed in close relation to the building code development and the preferred design concepts. Besides response phenomena and typical damage patterns which have been observed after other earthquakes worldwide, an attempt is made to investigate parameters with high damage potential according to [3].