Humanizing smart cities: Lisbon case study

Smart cities are a growing phenomenon, largely driven by globalization and the digital revolution, which have enabled hyper connectivity, between people and between machines. Although there are more and more cities joining their efforts to become smart, the definition of a smart city is not consensual, there is a wide variety of definitions, which focusing on different aspects of it, cannot be considered wrong. However, it is known that a city, regardless of its intelligence, is made of people and for people, so its ultimate goal must be the constant improvement in the quality of life of its citizens. For this to happen, political power must be able to involve citizens in ongoing projects and initiatives designed to increase the city's intelligence. With this work, through the application of a questionnaire, it is intended to understand to what extent citizens are aware of the ongoing initiatives to turn Lisbon into a smart city, what is their degree of involvement during this process and what potential measures could be taken to encourage the active participation of the inhabitants in this same construction. In the end, it is expected that with the results, the Lisbon City Council, upon understanding the citizens' opinion, their perception of smart cities and the measures they think are crucial for their participation to increase, the municipality will take the measures needed to leverage the city's intelligence.info:eu-repo/semantics/acceptedVersio

Finite element modelling of masonry cross vaults: considerations on block interlocking and interface properties

Masonry cross vaults had been used for centuries in the roofing of European buildings, palaces and churches, representing nowadays an integral part of national cultural heritage. In this regard, a sound knowledge of the structural response of cross vaults under vertical and horizontal loads is fundamental for planning accurate and compatible conservation programs. Whereas a certain consensus on the static behavior of the cross vault under gravitational loads has been reached, still more efforts are requested for assessing its seismic capacity. In the present work, the finite element approach has been implemented with a particular attention to the block interlocking and interface elements. On the one hand, an appreciable accommodation between the real block arrangement and computational effort is shown. On the other hand, modelling the blocks with rigid-infinitely resistant elements leads the interface as the only source of physical nonlinearities. Paralleling recent works on the seismic behavior of masonry arches, the influence of the mechanical parameters of the interface elements is discussed. Comparisons between numerical and experimental results available in literature are presented in terms of ultimate strength capacity and failure mechanisms.- (undefined

A micro-mechanical model for the homogenisation of masonry

Masonry is a composite material made of units (brick, blocks, etc.) and mortar. For periodic arrangements of the units, the homogenisation techniques represent a powerful tool for structural analysis. The main problem pending is the errors introduced in the homogenisation process when large difference in stiffness are expected for the two components. This issue is obvious in the case of non-linear analysis, where the tangent stiffness of one component or the tangent stiffness of the two components tends to zero with increasing inelastic behaviour.The paper itself does not concentrate on the issue of non-linear homogenisation. But as the accuracy of the model is assessed for an increasing ratio between the stiffness of the two components, the benefits of adopting the proposed method for non-linear analysis are demonstrated. Therefore, the proposed model represents a major step in the application of homogenisation techniques for masonry structures.The micro-mechanical model presented has been derived from the actual deformations of the basic cell and includes additional internal deformation modes, with regard to the standard two-step homogenisation procedure. These mechanisms, which result from the staggered alignment of the units in the composite, are of capital importance for the global response. For the proposed model, it is shown that, up to a stiffness ratio of one thousand, the maximum error in the calculation of the homogenised Young's moduli is lower than five percent. It is also shown that the anisotropic failure surface obtained from the homogenised model seems to represent well experimental results available in the literature.FCT - Erzincan Üniversitesi(PRAXIS-C-ECM-13247-1998

Possibilidades e aplicações de ensaios não destrutivos

Comunicação apresentada no Encontro sobre a Madeira e suas Aplicações Nobres : "Bem utilizar a madeira", Lisboa, Portugal, 22 Novembro 2005

Three-dimensional limit analysis of rigid blocks assemblages. Part II : load-path following solution procedure and validation

A novel solution procedure for the non-associated limit analysis of rigid blocks assemblages is proposed. This proposal produces better solutions than previously proposed procedures and it is also able to provide an insight into the structural behaviour prior to failure. The limit analysis model proposed in Part I of this paper and the solution procedure are validated through illustrative examples in three-dimensional masonry piers and walls. The use of limit analysis for three-dimensional problems incorporating non-associated flow rules and a coupled yield surface is novel in the literature

Plastic torsion on frictional joints and three-dimensional limit analysis of masonry structures

The plastic torsion of arbitrarily shaped, frictional joints is established together with its interactions with bending moments and shear forces. In order to solve limit analysis problems, a piecewise linear approximation of the yield function for rectangular joints is proposed. The proposal is incorporated into a model for limit analysis of masonry structures regarded as rigid block assemblages interacting through no tension, frictional joints. An example validates the proposal.Consejo Nacional de Ciencia y Tecnología of Mexico. Fundação para a Ciência e e Tecnologia (FCT) - Project SAPIENS 33935-99

3D homogenized limit analysis of masonry buildings under horizontal loads

The current confidence levels in the ability to provide buildings with adequate resistance to horizontal actions do not easily apply to historic and existing masonry structures. Limit analysis is often not sufficient for a full structural analysis under seismic loads, but it can be profitably used in order to obtain a simple and fast estimation of collapse loads. Often, the limit analysis of ancient masonry structures is used in the context of several simplifications, the assumptions about the collapse mechanisms being the most relevant. Aiming at a more general framework, a micromechanical model developed previously by the authors for the limit analysis of isolated in- and out-of-plane loaded masonry walls is extended here and utilized in the presence of coupled membrane and flexural effects. In the model, the elementary cell is subdivided along its thickness in several layers, where fully equilibrated stress fields adopting a polynomial expansion are assumed. The continuity of the stress vector on the interfaces between adjacent sub-domains and anti-periodicity conditions on the boundary surface are further imposed. Linearized homogenized surfaces for masonry in six dimensions are obtained and implemented in a FE limit analysis code, and two 3D case studies are analyzed making use of the kinematic theorem of limit analysis. From the results, the approach proposed is validated and its usefulness for solving engineering problems is demonstrated.Fundação para a Ciência e a Tecnologia (FCT) - POCTI-ECM-61671-2004MIUR COFIN 200