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Introduction: Buildings that collapse or are damaged by earthquakes are responsible for the majority of earthquake-related casualties. High-precision building data are the key to improving the accuracy of risk assessments of earthquake disaster loss. Many countries and regions have also proposed varying regional building exposure models, but most of these models are still based on administrative-level (city or county) statistical data; furthermore, they cannot accurately reflect the differences among buildings in different towns or villages. Methods: Although field investigation-based "township to township" methods can obtain more accurate building inventory data, considering costs and timeliness, remote sensing and other diverse data should be combined to acquire building data. Based on the field survey data of three cities in shanxi Province, combined with Global Human Settlement Layer (GHSL) data, this study is conducted on building inventory data. Data regarding the proportion of each building type and corresponding lethality level in each township are obtained based on the classification of building height, and the overall lethality level at the building level and township level is calculated on this basis. Results: The fitting results between the calculated results and the field survey results are good, the error is within 0.15, and the fitting R2 values of Xian, Baoji and Ankang are 0.6552, 0.5788 and 0.5937, respectively. Therefore, an earthquake disaster loss risk assessment is conducted based on the building level. Discussion: The findings indicate that the risk of casualties caused by the same building type can vary by city. Generally, the areas with high disaster loss risk in the three cities are distributed mainly in urban areas; the disaster loss risk in the newly built areas of each city is relatively low. According to the quantitative assessment results for each city, Xi'an has the highest loss risk, while Baoji and Ankang have the same loss risk. Based on the method constructed in this paper, we can realize the quantitative assessment of earthquake disaster loss risk at the building level to better target pre-earthquake emergency preparation and post-earthquake auxiliary decision-making. [ABSTRACT FROM AUTHOR]

Bridge maintenance and safety are key goals for transportation management companies, considering that several vulnerability sources can affect these assets. Although necessary and hardly replaceable, traditional surveillance techniques represent time‐ and cost‐consuming activities that cannot be widely employed on the entire infrastructural portfolio. Hence, innovative techniques could be exploited, among which the use of Interferometric Synthetic Aperture Radar (InSAR). InSAR is a well‐known remote sensing technique that allows to reconstruct the displacement time‐series of persistent scatterers (PS) on the Earth's surface. The current available PS time series present different levels of spatial accuracy and temporal frequency, which depend on satellite data source. On this base, the paper deals with the evaluation of displacement scenarios for existing RC bridges, by means of two different popular satellite time‐series datasets: Sentinel‐1 and COSMO‐SkyMed. In detail, the analysis of the interferometric products provides different out‐comes, which are discussed in this paper. Pros and cons are provided with reference to a real‐life case study, showing differences in terms of geometry, resolution, and displacement results. [ABSTRACT FROM AUTHOR]

The paper is focused on the probabilistic structural assessment of existing prestressed concrete girder bridges accounting for traffic loads. Particularly, this study concerns the fragility of the class of prestressed concrete girder bridges characterized by post‐tensioned tendons built in the 1960‐1970 period. The structural safety of such bridge class can be affected by construction errors involving voids in the ducts and degradation conditions in terms of tendon corrosion which can be hardly detected during on‐site visual inspections. The study applies a fragility analysis algorithm to investigate the probabilistic response under traffic loads considering the uncertainty related to material and geometric variables for different scenarios of tendon corrosion. The algorithm is applied for two typical case‐study configurations of simply supported superstructures. The achieved results can be considered as a basis for future typological studies which can be used as a decision support for transport managers to define risk‐informed refined assessment plans. [ABSTRACT FROM AUTHOR]