Capacity curves obtained from nonlinear static analyses are widely used to perform seismic assessments of structures as an alternative to dynamic analysis. This paper presents a novel ‘en masse’ method to assess the seismic vulnerability of urban areas swiftly and with the accuracy of mechanical methods. At the core of this methodology is the calculation of the capacity curves of low-rise reinforced concrete buildings using neural networks, where no modeling of the building is required. The curves are predicted with minimal error, needing only basic geometric and material parameters of the structures to be specified. As a first implementation, a typology of prismatic buildings is defined and a training set of more than 7000 structures generated. The capacity curves are calculated through push-over analysis using SAP2000. The results feature the prediction of 100-point curves in a single run of the network while maintaining a very low mean absolute error. This paper proposes a method that improves current seismic assessment tools by providing a fast and accurate calculation of the vulnerability of large sets of buildings in urban environments.

This work summarises the strategy adopted in the European research project PERSISTAH. It aims to increase the resilience of the population, focusing on the existing primary schools in the Algarve (Portugal) and Huelva (Spain) regions. Software was developed to assess the seismic safety of these schools, considering different earthquake scenarios. Seismic retrofitting measures were studied and numerically tested. Some of them were also implemented in the retrofitting activities of two case study schools (one in each country). It was found that the adopted ground motion prediction equations (GMPEs) considerably affect the results obtained with the software, especially for offshore earthquake scenarios. Furthermore, the results show that the masonry buildings would be the most damaged school typologies for all the scenarios considered. Additionally, a set of guidelines was created to support the school community and the technicians related to the construction industry. The goal of these documents is to increase the seismic resilience of the population. Different activities were carried out to train schoolteachers in seismic safety based on the guidelines produced, obtaining positive feedback from them.

The seismic retrofitting of reinforced concrete (RC) buildings has been widely analysed. Most of the solutions proposed are focused on the building's structure improvement. However, the effects of ground-improvement techniques combined with the building's structure-improvement techniques have not been usually analysed. Therefore, this paper aims to assess the seismic performance of a building by adding different seismic retrofitting techniques in the structure and the ground. A RC school building is proposed in this work. This has been selected because it was constructed prior to the current seismic code. Schools are some of the buildings most vulnerable to earthquakes. This is due to the low adult/child ratio. This paper is framed within the PERSITAH project (Projetos de Escolas Resilientes aos SISmos no Território do Algarve e de Huelva, in Portuguese). The main goal of the project is to analyse the seismic vulnerability of schools' buildings located in the Algarve-Huelva region. This area is characterized by earthquakes of long-return period and large magnitude. Therefore, the population is not aware of the seismic hazard of the area. Different seismic retrofitting techniques have been added to the building and they have been compared and analysed. The techniques have consisted of the addition of X-bracings within the buildings' bays, steel jackets in columns and soil injection grouting. These solutions have been added both individually and combined to generate hybrid models. Nonlinear static analyses have been carried out to determine the seismic performance of the building including each technique. The N2-method has been considered to obtain the performance displacement. Moreover, the damage level probability and the mean damage index have been determined for each retrofitting technique. Results have shown that the addition of X-bracings is the most efficient solution. However, this solution causes a great architectural impact. Therefore, the solution of steel jackets and/or injection grouting emerges as an interesting alternative.