http://repositorio.lnec.pt:8080/jspui/handle/123456789/39 Sat, 04 Apr 2026 19:07:57 GMT 2026-04-04T19:07:57Z http://repositorio.lnec.pt:8080/jspui/handle/123456789/1018987 Development of an integrated software framework for enhanced hybrid simulation in structural testing Tekeste, G.G.; Correia, A.A.; Costa, A. Hybrid simulation integrates numerical and experimental techniques to analyze structural responses under static and dynamic loads. It physically tests components that are not fully characterized while modeling the rest of the structure numerically. Over the past two decades, hybrid testing platforms have become increasingly modular and versatile. This paper presents the development of a robust hybrid testing software framework at the National Laboratory for Civil Engineering (LNEC), Portugal, and evaluates the efficiency of its algorithms. The framework features a LabVIEW-based control and interface application that exchanges data with OpenSees via the OpenFresco middleware using a TCP/IP protocol. Designed for slow to real-time hybrid testing, it employs a predictor–corrector algorithm for motion control, enhanced by an adaptive time series (ATS)-based error tracking and delay compensation algorithm. Its modular design facilitates the integration of new simulation tools. The framework was first assessed through simulated hybrid tests, followed by validation via a hybrid test on a two-bay, one-story steel moment-resisting frame, where one exterior column was physically tested. The results emphasized the importance of the accurate system identification of the physical substructure and the precise calibration of the actuator control and delay compensation algorithms. Tue, 15 Apr 2025 00:00:00 GMT http://repositorio.lnec.pt:8080/jspui/handle/123456789/1018987 2025-04-15T00:00:00Z http://repositorio.lnec.pt:8080/jspui/handle/123456789/1018293 sanity check for earthquake recurrence models used in PSHA of slowly deforming regions: the case of SW Iberia Ramalho, M.; Matias, L.; Neres, M.; Carafa, M.; Carvalho, A. M.; Teves-Costa, P. Probabilistic seismic hazard assessment (PSHA), despite its deep criticism, is still the most common tool used to decide on the acceptable seismic risk and corresponding mitigation measures. We propose two consistency tests to address the variability of earthquake generation models found in PSHA studies: (i) one rule-of-thumb test where the seismic moment release from the model is converted to an average slip on a typical fault and compared with known plate kinematics or GNSS deformation field and (ii) a test where using a neotectonic model the computed deformation is converted into seismic moment release and to a synthetic earthquake catalogue. We apply these tests to W and SW Iberia slowly deforming region, where two earthquake source areas are investigated: (1) the Lower Tagus Valley, one of the largest seismic risk zones of Portugal; and (2) the offshore SW Iberia area, considered to be the source for the 1 November 1755 event (M ∼ 8.7). Results show that some of the earthquake source models should be considered suspicious, given their high/low moment release when compared to the expected values from GNSS observations or neotectonic modelling. This analysis allowed for a downgrade of the weight of poorly compliant models in the PSHA analysis, and thus for a more realistic hazard assessment, and can be integrated in other studies of similar settings. Sat, 01 Jan 2022 00:00:00 GMT http://repositorio.lnec.pt:8080/jspui/handle/123456789/1018293 2022-01-01T00:00:00Z http://repositorio.lnec.pt:8080/jspui/handle/123456789/1018292 Shake-table testing of two u-shaped RC walls: overview of the project Eries-ALL4waLL Almeida, J.P.; Hoult, R.; Bertholet, A.; Candeias, P.; Carvalho, A. M.; Correia, A.A.; Cumunel, G.; Doneux, C.; Han, Y.; Isaković, T.; Janevski. A.; Lo Feudo, S.; Mihaylov, B.; Orgnoni, A.; Payen, B.; Palermo, D.; Pinho, R.; Ribeiro, F.; Simar, A.; Luísa Sousa, M. This paper summarises the project ERIES-ALL4wALL, “Smart ALLoys for WALLs: towards durable structures with long service lives and minimal seismic residual displacements”, which was funded through the Engineering Research Infrastructures for European Synergies (ERIES) Transnational Access program. The project advances the understanding of the seismic behaviour of reinforced concrete (RC) U-shaped core walls by investigating two factors that commonly contribute to poor structural response and limit post-earthquake serviceability, namely torsional effects and excessive residual displacements. The latter can be minimised through a mitigation principle that consists in replacing partially some of the longitudinal steel reinforcement at the wall base by smart alloy rebars. The project aims at demonstrating this technological innovation, contributing to ensure target performances for buildings with significantly longer service lives, which should be an aim for sustainable design and assessment. In scientific and technical terms, the project is concretized in three main fronts of research: (i) the shake-table testing of two large-scale U-shaped RC wall units in the National Laboratory for Civil Engineering (LNEC), in Lisbon – namely: one conventionally-reinforced unit, and a second one including the smart alloy rebars; (ii) the development of state-of-the-art and state-of-the-practice simulation models to estimate the response of the test units; (iii) the application of a set of novel instrumentation techniques, namely distributed fiber optic sensors along several reinforcing bars, video-based tracking measurements, an OptiTrack motion capture system, and extensive conventional instrumentation; in essence, it means these two units are the most extensively monitored walls so far tested in shake-table testing. The paper starts by addressing the project motivation, providing a global description, and listing its objectives. It then goes on to justify the sources of innovation and impact, as well as the articulation between the unique synergistic features of the assembled team of 15 user group members. It concludes with a description of the experimental programme, an overview of the employed numerical simulation techniques, and some leading results of the first wall unit tested. More complete and comparative results of the performance of both units, and of the associated blind prediction competition, will be unveiled during the conference presentation. Sat, 01 Jun 2024 00:00:00 GMT http://repositorio.lnec.pt:8080/jspui/handle/123456789/1018292 2024-06-01T00:00:00Z http://repositorio.lnec.pt:8080/jspui/handle/123456789/1018289 National seismic risk assessment: an overview and practical guide. Luísa Sousa, M.; Tsionis, G. In order to promote an effective approach to the prevention of and preparedness for disasters, the countries participating in the Union Civil Protection Mechanism (UCPM) shall develop risk assessments, risk management capability assessments and disaster risk management planning at national or appropriate sub-national level. The European Commission is providing scientific support to the countries participating in the UCPM, publishing updated guidelines to facilitate the development of their National Risk Assessments (NRAs). Earthquake is among the most common hazards considered in NRAs prepared by the countries participating in the UCPM. Indeed, in 2018 NRAs, more than 20 countries performed risk assessment for earthquakes, and some considered cross-border and cascading effects, such as tsunami, landslides, disruption of infrastructure and industrial accidents. This paper surveys and summarises the current state of research that can be utilized for national seismic risk assessment. It aims to facilitate the development of consistent NRAs with respect to earthquakes and ensure their utility in seismic risk management planning. It also aims to support the use of the new reporting guidelines on disaster risk management among countries participating in the UCPM. The seismic risk assessment process is described as outlined in ISO 31000: 2018. A wealth of hazard, exposure, vulnerability and damage-to-loss models, methodologies and tools are presented to serve the purpose of conducting national seismic risk assessment. References to relevant European research projects, good practices, and software to support the assessment are also provided. Wed, 01 Jan 2025 00:00:00 GMT http://repositorio.lnec.pt:8080/jspui/handle/123456789/1018289 2025-01-01T00:00:00Z