Capítulos de livros

Though an important subject that has been investigated for several decades, the full understanding of the alkali release from aggregates, its contributing factors and role in the alkali-silica reaction still remains a challenge for the scientific community. Recently, the RILEM AAR-8 test method was developed and several improvements to thismethodology have already been proposed. In this paper, automated scanning mineralogy (QEMSCAN®) is introduced as a complementary tool for petrographic characterization in order to better understand thefactors contributing to the alkali release fromaggregateswith a similarmineralogy.Itwas used to examine distinctive textures, grain sizes and alteration of amylonite, a cataclasite, a gneiss, a granite and an altered granite. The QEMSCAN® analysis enabled a more thorough understanding of the aggregates whilst complimenting the optical petrography.

The most common standards ruling the assessment of the potential reactivity of aggregates consider that the petrographic analysis should be followed, in the first step, by accelerated mortar-bar tests and, in case of a positive result, by concrete-prism tests.However, experience has shown that these different approaches often provide contradictory results in the classification of an aggregate as innocuous or potentially reactive. Discussion about the inaccuracy of the accelerated mortar-bar test for some slow reactive aggregates has been puzzling the scientific community andsome explanations have been suggested to explain this fact.In the present work, deformed rocks used as aggregates, previously submitted to accelerated mortar-bar tests and to concrete-prism tests, are analyzed regarding different grain sizes. The research aims to define the role of crushing mechanisms in the destruction of crystals originated from sub-graining, due to tectonic deformation,during the production of the smaller particles requested by the mortar-bar test. With this purpose, the petrographic analysis of the rocks selected, and their correspondent sand size aggregates has been done using the image-based open software JMicrovision

In previous research, volcanic rocks from the Azores Islands (Portugal), Brazil, Canada, Canary Islands (Spain), Hawaiian Islands (USA), Iceland, Japan, Mozambique, New Zealand, Norway, and Turkey were studied to assess their potential reactivity to alkalis. The analyzed samples correspond to basalt, andesite and rhyolite. Several tests were performed, namely, petrographic characterization by optical microscopy and scanning electron microscopy, bulk rock chemical analysis, accelerated mortar-bar test and concrete prism test.In volcanic rocks, the possible reactive forms of silica are not only of minute size, and hard to identify, but are also usually present in very low content, and often below the detection limits used in chemical bulk rock analysis.This study reports the results obtained in additional tests to characterize the aforementioned aggregates: 1) the phosphoric acid method, by dissolution of silicates of the rock reduced to powder, preserving the free silica forms of the sample; and 2) the gel-pat test, applied on lengthwise slabs of concrete prisms preparedwiththe selected aggregates, to obtain the possible presence of reactive components, in particular volcanic glass and free silica polymorphs.The results from the two tests are presented and the possible correlations with the results from the petrographic characterization and from the expansion tests are discussed.

This chapter proposes an introductory conceptual framework to better understand some aspects of everyday relations of people and spaces. From the perspective of anthropology of space, it first provides a reflection on issues that are important for understanding these relationships, to then, in a second step, address the relevance of walking as a method to trigger a sensitive path. This chapter aims to raise the interest for urban planning that is more attentive to the multidimensionality of socio-territorial relations. To explore the sensitiveness of urban space it is important to consider (a) the perspective of users in terms of symbolic dimensions, socio-spatial and cultural practices, and sense of happiness and well-being; (b) the articulation between behavioural dimensions, sociocultural dynamics and the environment; (c) the approximation of concepts and categories to understand space from the perspective of different disciplines. Keywords - Attentiveness, socio-territorial relations, walking, urban planning

This work collects information about laboratory tests to evaluate the properties of agro-industrial wastes used for thermal insulation building materials considering them individually and in composits. It focuses on bio-susceptibility, as one of the main aspects to consider for bio-based building products.

The growing interest in preserving the built heritage is a driving force towards the search for new rehabilitation solutions compatible with the original construction techniques of ancient buildings. For the design of an adequate reinforcement solution, it is necessary to know in detail the building to be rehabilitated, as well as its original constructive solutions and materials.This paper presents the results of an experimental campaign on samples of air lime-based laying and coating mortars, extracted from an old masonry building in the historic center of Lisbon, built in 1910, during the rehabilitation works. The different parameters analyzed allow for the composition characterization and evaluation of their mechanical, physical and chemical properties. Based on this characterization, the influence of these mortars on the overall behavior of load-bearing walls of buildings belonging to the typology under study is also evaluated.Considering the results obtained in the characterization tests for the mortars in study, it was verified that the binder used in both mortars was air lime. The values for compressive strength, modulus of elasticity and the curves obtained in the capillarity and drying tests, are also compatible with this type of mortars. It was determined that the mortars are similar in terms of physical and mechanical characteristics, to Portuguese mortars studied in current buildings of the same historical period. This type of information is crucial in a structural analysis and allows to identify materials compatible with the original ones that can be used in rehabilitation interventions.

Although no specific definition is designated for this term, this concept has been previously defined based on the field of application and utilization. The blue economy refers to the sustainable utilization of ocean and coastal resources for economic growth, improved livelihoods, and job creation while preserving the health of marine ecosystems. It is also regarded as an economic concept encompassing various economic activities in the ocean and coastal area, including traditional activities such as fishing, shipping, and shipbuilding, as well as newer activities such as offshorewind and wave energy, ocean-based aquaculture,and marine biotechnology. It is defined as the range of economic activities in the coastal zone and on the ocean, including shipping, fishing, oil and gas extraction, tourism, and renewable energy production. Generally, the blue economy mainly focuses on the responsible extraction and utilization of marine resources required to enhance ocean-based economies while adopting more balanced conservation measures to ensure resource sustainability.

Resumo: Ambiente construído é um conceito amplo e difuso; talvez essa seja uma de suas virtudes capitais. A pesquisa nessa área de fronteiras tão impre­cisas permite abordagens de temas, escalas e métodos diversificados. Neste livro, a reunião de ensaios feitos por pesquisadores de diferentes países sobre variados tópicos, com apropriações metodológicas tão diversas, reafirma o caráter múltiplo desse campo. Nesta ótica, destaca-se o papel de uma observação sistemática e minuciosa das complexas interações que resultam da relação entre os múltiplos e diversificados usos dos espaços públicos urbanos, as apropriações, contra apropriações, representações do espaço e respectivas tem­poralidades envolvidas, considerando a sua ligação com propostas arquitetônico-urbanísticas de desenho e intervenção. Este livro é o registro de um momento do campo, mas também representa a possibilidade de novas incursões que podem alargar suas fronteiras. Abstract: Built environment is a broad and diffuse concept; perhaps this is one of its capital virtues. Research in this area of such inaccurate bound­aries allows approaches from diverse themes, scales and methods. In this book, the gathering of essays by researchers from different countries on various topics, with such diverse methodological ap­propriations, reaffirms the multiple character of this field. In this perspective, it highlights the role of a systematic and thorough observation of the complex interactions that result from the relationship between the multiple and diverse uses of urban public spaces, appropriations, against appropriations, representations of space and respective temporalities involved, considering their connection with architectural-urbanistic proposals of design and intervention. This book registers a specific moment in the field but it also rep­resents the possibility of further inroads that may broaden its borders.

The use of alternative materials, in particular industrial by-products and waste materials, in the construction oftransport infrastructures and geotechnical works, has been promoted across the world. Nonetheless, considering that, in most situations, the application of some of these materials is fairly recent, little information is available on the long-term performance of the infrastructures in which they were used. This work mentions some characteristics of the Inert Steel Aggregate for Construction (ISAC). It presents some results related to the evolution in the surface characteristics and the structural behaviour of a field trial built on a road section in Portugal. ISAC was used in the embankments and pavement layers. The visual inspection, the results of the mechanical tests performed, and the values of the settlements measured on the surface markings about ten years after the section is open to traffic led to conclude that the pavement in the zone where ISAC was used as a construction material is, in general, in a better condition and presents better structural performance than the adjacent areas built with natural materials. The embankment's maximum settlements in the areas with ISAC were similar to the ones observed in the adjacent areas.

Cementitious materials have a considerable global warming footprint. This is due mainly tothe cement incorporated. For a tonne of cement produced other 800 kg of CO2 [1] are releasedinto the atmosphere.According to the European Sustainable Development Goals, cement industry should becomecarbon neutral by 2050. To meet this goal, the European Cement Association (Cembureau)developed a Roadmap with specific guidelines by 2050 based on five approaches (5C). Thefirst four are focused on improvements in clinker production, cement formulation,construction processes and concrete formulations. The last 5C is re-carbonation of thecementitious materials.This research investigates the CO2 absorption capability of recycled aggregates (RA) fromconstruction and demolition wastes (CDW), when submitted to a forced carbonation. It isknown that CDW still have some potential to CO2 capture, which is a long-term and securecarbon storage. For that purpose, several CDW were collected from recycling plants, fromselective demolitions and from concrete plants.It was concluded that RA when submitted to forced carbonation absorb between 47 to 315 kgof CO2 per tonne of cement paste, which has a potential to meet the re-carbonation targetsestablished by the roadmaps to carbon neutrality.