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One of the significant challenges concerning earthquake risk mitigation is the seismic vulnerability assessment of existing buildings that were not designed according to modern codes. Several authors recognized that the infill walls might significantly affect the seismic response of reinforced concrete structures (RC). Still, they are treated as “non-structural” elements by the national and international codes and they are not considered in the seismic assessment of existing RC buildings, and their impact on the seismic response of the structure is neglected. This manuscript aims to study the seismic response of an 8-storey RC structure simulated in the software OpenSees with and without masonry infill walls. The masonry infill walls were simulated considering their in-plane and out-of-plane (OOP) behaviour interaction. Two different studies were performed. First, the study of the impact of the infill walls in the global building seismic response and after that the study of the infill walls seismic performance. Several incremental dynamic analyses were carried out for these studies to study floor accelerations and velocities and determine peak floor acceleration and peak floor velocity. At the same time, floor response spectra were drawn for the design peak ground acceleration, according to Eurocode 8. Acceleration-Displacement Response Spectrum is also obtained and presented according to Eurocode 8. The OOP accelerations and OOP velocities of the masonry infill walls were recorded for all the input ground-motions. The maximum OOP accelerations and velocities reached by the infill panels at each floor were obtained and discussed. The respective infill acceleration and infill acceleration-displacement response spectrum and infill velocity response spectra were then derived and presented. Finally, the amplification of the infills OOP accelerations along the building height will be evaluated and compared with the Eurocode 8 demands. The results show that the infills increase the peak floor accelerations and modify the floor response spectra. The infills OOP accelerations are always 1.2–2 times higher than PFA. The infills acceleration response spectra do not change with the increase of the building height.

Road safety modeling enables the development of crash prediction models and the investigation of which factors contribute to crash occurrence. Developing multivariate response models is also valuable, but such models are currently under-exploited. Machine learning techniques, especially artificial neural networks (ANN), have been presented as possible alternatives. Furthermore, selecting a proper roadway segmentation is one of the first tasks in the standard crash modeling workflow. However, this is a challenging task, especially in terms of choosing a segment length. This article presents a study of the influence of segment length on the development of multivariate response models (i.e., three response variables: property damage only crashes, injured victims crashes, and fatal crashes). The models use ANN for a road segment of a Brazilian divided multilane highway. The highway to be modeled was divided into segments with 10 different fixed lengths. The model characterization included geometric and operational data available for the years from 2011 to 2017. The models were evaluated in terms of errors and by residual plot analysis. The 5-km segment of the northbound carriageway and the 4.5-km segment of the southbound carriageway presented the smallest errors and the highest values of R2. The residual analyses confirmed the trend to improve the model with the greater segment lengths. This was clear by the residues' distribution around zero, except for the output “Fatal crashes”. The better performance of the longer segments models was expected because these models aggregate more crashes into one segment. The reduction of no crash observations also facilitated the improvement of the models' goodness-of-fit. The use of ANNs also revealed its potential value. However, it is still important to seek strategies to deal with the excess of zeros in fatal crashes; a problem that also occurs in the traditional statistical modeling process.

The worldwide generation of construction and demolition waste is about 30% to 35% of the total solid waste produced annually. In addition, the extraction of minerals leaves a high-grade environmental liability with tailings, such as kaolin clay, Brazil being one of the countries with the largest deposits and production of this mineral in the world. The kaolin clay extraction serves several industries such as ceramics, crockery, and paper, among others. The objective of this work is to insert these two wastes as raw material of construction elements, specifically masonry concrete blocks, thus giving an end to the residues, demonstrating their reutilization potential. Here, blocks were manufactured with replacement of natural aggregates, stone powder, and sand, by construction and demolition waste and of kaolin clay waste. The replacement percentages were up to 34% and 16%, respectively. The blocks made with pneumatic vibration compacting procedure presented strength beyond than what is established by norm, thus giving a favorable perspective of use for these residues as building elements.

Short-span railway bridges subjected to high-speed traffic are structures where dynamic effects are mandatory. Additionally, the variability associated with materials and geometric characteristics introduces uncertainty to the safety assessment of railway traffic. This work discusses the current norms limit for vertical deck acceleration regarding the evaluation of stability on ballasted tracks, as stated on Annex A2 of EN1990. A probabilistic methodology to define a partial safety factor is presented, employing dynamic analyses and Monte Carlo simulations. The evaluation of a case study is presented for a single-span filler-beam bridge of the Portuguese Railways Network. The results allow the definition of deterministic design scenarios that are compared to the simulations outcome. Conclusions show consistent partial safety factors with the norms limit, contributing to further discussion of this factor. (c) 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Esse trabalho tem como objetivo analisar os impactos econômicos causados à indústria da construção civil com a manifestação da pandemia da Covid-19 e as suas diversas medidas de combate e prevenção adotadas, além de evidenciar a importância de um sistema eficaz de gerenciamento. Trata-se de um estudo descritivo, do tipo revisão integrativa da literatura, com abordagem qualitativa, realizado nas bases de dados: SCIELO e Google Acadêmico. As buscas nos bancos de dados resgataram um total de 36 artigos, dos quais foram incluídos na amostra apenas 11. Os artigos utilizados evidenciaram que a indústria da construção civil se adaptou às restrições impostas em meio a pandemia e demonstrou ser um setor extremamente importante para a economia brasileira, onde mesmo durante a referida crise sanitária, auxiliou na ampla criação de empregos e obteve êxito financeiro. O tempo atual mostra-se desafiador para todos os segmentos e o pós-pandemia ainda é algo imprevisível. Contudo, é necessário que o setor da construção civil adquira formas viáveis de continuar a desenvolver-se, já que representa um dos setores mais importantes para a economia do país.

Introduction In a context of increasing automation of road transport, many researchers have been dedicated to analyse the risks and safety implications of resuming the manual control of a vehicle after a period of automated driving. This paper performs a systematic review about drivers’ performance during takeover manoeuvres in driving simulator, a tool that is widely used in the evaluation of automated systems to reproduce risky situations that would not be possible to test in real roads. Objectives The main objectives are to provide a framework for the main strategies, experimental conditions and results obtained by takeover research using driving simulation, as well as to find whether different approaches may lead to different outcomes. Methodology First, a literature search following the PRISMA statement guidelines and checklist resulted in 36 relevant papers, which were described in detail according to the type of scenarios and takeover events, drivers’ engagement in secondary tasks and the assessed takeover performance measures. Then, those papers were included in a meta-analysis combining PAM clustering and ANOVA techniques to find patterns among the experimental conditions and to determine if those patterns have influence on the observed takeover performance. Conclusions Less complex experiments without secondary task engagement and conducted in low-fidelity simulators are associated with lower takeover times and crash rates. The takeover time increases with the time budget of the first alert, which reduces the pressure for a driver’s quick intervention.

Dissertação de Mestrado em Mecânica dos Solos e Engenharia Geotécnica apresentada à Faculdade de Ciências e Tecnologia Em meio urbano é muito frequente encontrar fortes condicionalismos à realização de escavações uma vez que grande parte do subsolo já se encontra ocupado por outras infraestruturas. A existência destas torna extremamente complexo o faseamento construtivo e as medidas a adotar na realização da escavação, uma vez que geralmente não é permitido que a mesma comprometa as infraestruturas existentes. Nesta tese apresenta-se o caso da escavação do edifício do Lote I da Quinta dos Candeeiros, Moscavide, Lisboa, onde a realização de uma escavação para a construção de duas caves interfere diretamente com o túnel da Linha Vermelha do Metropolitano de Lisboa. Tal interferência obrigou a que em fase de projeto tivessem de ser adotadas medidas construtivas suplementares que passaram pela concessão de um engenhoso mecanismo de distribuição das tensões provenientes do edifício no solo, que evitasse que o túnel fosse afetado pela escavação. Para além do enquadramento na temática realizado através de uma completa revisão bibliográfica, estudou-se, com recurso a análises numéricas e comparações com a instrumentação instalada no próprio túnel e nas estruturas de contenção, até que ponto a solução numérica concebida se ajusta aos resultados da monitorização. A análise numérica foi submetida a uma calibração, resumida em quatro cálculos, com diferentes parâmetros mecânicos e modelos constitutivos, sendo eles Mohr-Coulomb e Hardening Soil. O comportamento do túnel e da escavação esteve em acordo com o que era expetável a partir da revisão bibliográfica. Ocorreu empolamento do fundo da escavação e do túnel, na zona que está nas proximidades da escavação. Além disso, verificou-se que o comportamento do túnel depende de sua posição em relação à escavação, podendo sofrer divergência, convergência e/ou distorção. In urban areas, it is very common to find strong constraints to carrying out excavations since a large part of the underground is already occupied by other infrastructure. The existence of these makes the construction phasing and the measures to be adopted in carrying out the excavation extremely complex, since it is generally not allowed to compromise the existing infrastructure. This thesis presents the case of the excavation of the lot I building at Quinta dos Candeeiros, Moscavide, Lisbon, where the excavation for the construction of two cellars directly interferes with the Red Line tunnel of the Lisbon Subway. This interference forced that, in the design phase, supplementary constructive measures had to be adopted, including the concession of an ingenious mechanism for distributing the tensions from the building on the ground, which would prevent the tunnel from being affected by the excavation. In addition to framing the theme carried out through a complete literature review, this thesis seeks to study in detail, and using numerical analyses, the merit of the solution found, evaluating the extent to which the tunnel can be affected. In addition to the framework on the subject carried out through a complete bibliographic review, it was studied, using numerical analyzes and comparisons with the instrumentation installed in the tunnel itself and in the retaining structures, to what extent the numerical solution conceived fits the results of the monitoring. The numerical analysis was submitted to a calibration, which can be summarized in four steps, with different mechanical parameters and constitutive models, namely Mohr-Coulomb and Hardening Soil. The behavior of the tunnel and excavation was in accordance with what was expected from the literature review. Heave occurred at the bottom of the excavation and at the tunnel, in the area situated close to the excavation. Furthermore, it was found that the behavior of the tunnel depends on its position in relation to the excavation, and may suffer divergence, convergence and/or distortion.

The study of polished concrete floors is relevant when related to technical and durability requirements, since its use is very common in places with large extensions. In this exploratory work, a comparison between the granolithic floor and the floor produced with glass waste was undertaken in order to verify the performance of the specimens, in addition to seeking a purpose for the glass, which is barely reused by society. The analyses carried out were: visual observation of the specimens, flexural tensile strength, compressive strength, and hard body impact strength test. Visual analysis identified more intense shine and larger amounts of holes on the surface of the specimens in which the glass waste was used. In the hard body impact strength test, the specimens produced with the glass waste presented superior results when compared to the reference specimens. In the flexural tensile strength test, the specimens produced with the glass waste presented lower results than the reference specimens, nevertheless both specimens showed satisfactory results. In the compressive strength test, the results obtained in both specimens were below the minimum required for industrial floors. The hard body impact strength test demonstrated the opposite: the specimens produced with the glass waste presented higher value than the specimens made with the granite.

Environmental legislation has placed constraints on the extraction of natural resources. As the construction industry is highly dependent on raw materials, more sustainable choices are required. This necessitates a cost-benefit analysis of the alternatives. Focusing on the benefits to the environment with the reduction of clay consumption, this work proposes an exploratory study on the production of unburned bricks with construction and demolition ceramic waste. The construction and demolition waste used was composed solely of ceramic brick remains, being crushed and sieved until reaching the desired granulometry to start the manufacturing process. Among three different properties, the bricks that obtained the best performance were those that incorporated higher content of construction and demolition ceramic waste.