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The present study shows the mercerization process (NaOH) and its effect on the physicochemical characteristics of rice straw. In total, 12 samples were analyzed, 3 as a comparative basis and 9 that were exposed to different concentrations of NaOH (1%, 2%, and 3%) and times, in hours, of exposure in an alkaline environment (1 h, 2 h, and 3 h). The loss of silica and reduction in lignin and hemicellulose contents identified in the chemical characterization allowed for a visualization of the surface topography and cross-section of the treated samples, making it possible to contrast them with the three untreated samples by comparing their roughness, the appearance of their pores, and the contractions of vascular bundles in their conductive tissue. An analysis of the data showed that the results between some treatments were similar, suggesting a reduction in resources in future research. The mechanical resistance allowed for identifying that the NaOH-1%-1 h treatment obtained a better mechanical resistance in the treated samples. However, NaOH-3%-1 h, with the third lowest resistance, obtained the highest % elongation compared to the other samples. These physicochemical changes with NaOH facilitate the selection of the treatment concerning the fiber–matrix interaction and final performance of the composite material that intends to use rice straw as a reinforcing fiber.

Around 56% of dwellings in Lima are constructed with confined masonry walls, and over 70% are built without engineering design and supervision. This building stock is exposed to the seismic activity of the Peruvian coastline. Then, in case of a severe earthquake, many of these buildings may suffer significant damage and eventually collapse, causing high economic losses and fatalities. Thus, it is essential to investigate the seismic behaviour of these constructions to understand their seismic vulnerability. This work studied the seismic performance of typically confined masonry walls built with hollow bricks based on cyclic in-plane tests. The imposed boundary conditions allowed the walls to behave as a cantilever. The influence of vertical precompression was also explored by performing separate tests with and without such load. Outcomes suggest that these walls may collapse after 0.5% drift. Also, mechanical features like stiffness degradation and damping values were calculated for different displacement limit states. Finally, fragility curves of confined masonry walls considering different unit types (i.e. solid, hollows, tubular), axial load ratio, and horizontal reinforcement are computed. The results demonstrate that tubular units should be forbidden as bearing walls, and horizontal reinforcement inside the walls improves their displacement ductility.

One of the noteworthy developments for the next generation of Eurocode 8 is the inclusion of a complete displacement-based design approach using nonlinear static or dynamic analyses and a set of verifications at the global or local levels, depending on the structural typology. This work investigates the consistency between such approach and classical force-based design applying behaviour factors, for reinforced concrete moment resisting frames. A set of structures designed according to the rules of the three novel ductility classes are used as case studies. Nonlinear static analyses are performed according to a new bilinearisation procedure, and target displacements are computed for the limit states of damage limitation, significant damage, and near collapse. The resulting structural demand, determined globally and in terms of the maximum local deformations among the members, is compared with the recommended values for global and local displacement capacities. Two alternative methods are then used to compute the components of the behaviour factor, which are critically confronted with the currently suggested upper-bound values for design. Finally, a procedure to harmonise displacement-based and force-based approaches is outlined, aiming at deriving values for the design behaviour factor that depend not just on the ductility class but also on additional design parameters which this investigation shows to influence the response.

This work compares the force-based (FB) design of moment resisting frames, as proposed in the next generation of Eurocode 8, with a complete displacement-based (DB)design approach, also introduced in the future code. After describing some of the evolutions in the FB approach, namely regarding the use of behaviour factor components, the main concepts of the DB approach are addressed, including the associated global and local verifications. The FB design of a set of reinforced concrete frames is described, followed by their nonlinear static analyses and DB-like verifications. These results are used to estimate the components of the behaviour factor, which are then compared with those adopted initially for the FB design. The level of conservativeness of the FB approach is estimated by comparing the ratios between the plastic deformation demand and capacity with the target values.

The use of simpler and less bulky equipment, with a reliable performance and at relative low cost is increasingly important when assembling sensing configurations for a wide variety of applications. Based on this concept, this paper proposes a simple, efficient and relative low‐cost fiber Bragg grating (FBG) interrogation solution using ultra‐short FBGs (USFBGs) as edge filters. USFBGs with different lengths and reflection bandwidths were produced in silica optical fiber and in poly(methyl methacrylate) (PMMA) microstructured polymer optical fiber (mPOF), and by adjusting specific inscription parameters and the diffraction pattern, these gratings can present self‐apodization and unique spectral characteristics suitable for filtering operations. In addition to being a cost‐effective edge filter solution, USFBGs and standard uniform FBGs in silica fiber have similar thermal sensitivities, which results in a straightforward operation without complex equipment or calculations. This FBG interrogation configuration is also quite promising for dynamic measurements, and due to its multiplexing capabilities multiple USFBGs can be inscribed in the same optical fiber, allowing to incorporate several filters with identical or different spectral characteristics at specific wavelength regions in the same fiber, thus showing great potential to create and develop new sensing configurations

The mechanical properties of adobe masonry were examined through a review of relevant experimental studies from different countries over the last 15 years. The results obtained by the reviewed studies were compared to obtain correlations between the different physical and mechanical properties evaluated. These correlations were compiled in this document and can be used in the rehabilitation of adobe buildings. However, the findings of this review show that the regulations tend to vary significantly to adapt to the local conditions.

Adobe is one of the oldest and most widely used building materials in the World. In the region of Aveiro, Portugal, traditional adobe construction represents about one-third of the existing buildings, some of which are of great architectural and patrimonial value. There is, however, a significant deterioration of several of these buildings, which need to be refurbished. A major difficulty for those involved in the process of structural assessment is the almost absence of references to adobe masonry mechanical properties. In this context, it is important to carry out the mechanical characterization of adobe masonry. Therefore, compression and shear tests were performed on adobe specimens from Aveiro’s region load-bearing adobe walls. Tests were carried out for two moisture contents (saturated and unsaturated) in order to analyze the influence of the frequent moisture conditions in the mechanical behaviour of the adobe masonries and their components. Experimental results allowed determining mechanical properties of adobe load-bearing walls, whose reference values can be used in their safety conditions assessment. It was also possible to formulate corrected equations of the Eurocode 6 for compressive and shear strength.

[EN] The sustainable rehabilitation of an historical construction can only be achieved if there is adequate knowledge about its state of conservation. To obtain such knowledge, reliable structural survey and diagnosis procedures need to be employed. An overall definition of the more important technical procedures that need to be considered is addressed to provide general guidelines for the structural survey and diagnosis of historical constructions. A more detailed description of some of the methods is then also performed. Several case studies are then presented to illustrate these approaches, emphasizing the importance of the technical inspection and survey data in the rehabilitation actions that were developed in each case study.

[EN] The sustainable rehabilitation of an historical construction can only be achieved if there is adequate knowledge about its state of conservation. To obtain such knowledge, reliable structural survey and diagnosis procedures need to be employed. An overall definition of the more important technical procedures that need to be considered is addressed to provide general guidelines for the structural survey and diagnosis of historical constructions. A more detailed description of some of the methods is then also performed. Several case studies are then presented to illustrate these approaches, emphasizing the importance of the technical inspection and survey data in the rehabilitation actions that were developed in each case study.

[EN] The sustainable rehabilitation of an historical construction can only be achieved if there is adequate knowledge about its state of conservation. To obtain such knowledge, reliable structural survey and diagnosis procedures need to be employed. An overall definition of the more important technical procedures that need to be considered is addressed to provide general guidelines for the structural survey and diagnosis of historical constructions. A more detailed description of some of the methods is then also performed. Several case studies are then presented to illustrate these approaches, emphasizing the importance of the technical inspection and survey data in the rehabilitation actions that were developed in each case study.

[EN] The sustainable rehabilitation of an historical construction can only be achieved if there is adequate knowledge about its state of conservation. To obtain such knowledge, reliable structural survey and diagnosis procedures need to be employed. An overall definition of the more important technical procedures that need to be considered is addressed to provide general guidelines for the structural survey and diagnosis of historical constructions. A more detailed description of some of the methods is then also performed. Several case studies are then presented to illustrate these approaches, emphasizing the importance of the technical inspection and survey data in the rehabilitation actions that were developed in each case study.

[EN] The sustainable rehabilitation of an historical construction can only be achieved if there is adequate knowledge about its state of conservation. To obtain such knowledge, reliable structural survey and diagnosis procedures need to be employed. An overall definition of the more important technical procedures that need to be considered is addressed to provide general guidelines for the structural survey and diagnosis of historical constructions. A more detailed description of some of the methods is then also performed. Several case studies are then presented to illustrate these approaches, emphasizing the importance of the technical inspection and survey data in the rehabilitation actions that were developed in each case study.

[EN] The sustainable rehabilitation of an historical construction can only be achieved if there is adequate knowledge about its state of conservation. To obtain such knowledge, reliable structural survey and diagnosis procedures need to be employed. An overall definition of the more important technical procedures that need to be considered is addressed to provide general guidelines for the structural survey and diagnosis of historical constructions. A more detailed description of some of the methods is then also performed. Several case studies are then presented to illustrate these approaches, emphasizing the importance of the technical inspection and survey data in the rehabilitation actions that were developed in each case study.

A study of the mechanical properties of adobe bricks collected from houses and land dividing walls in Aveiro district, Portugal, representative of existing traditional constructions, was conducted. Cylindrical adobe specimens were subjected to simple compression and splitting tests. From these tests it was possible to evaluate the strength capacity, stiffness and deformation evolution for increasing loading. Correlations between the evaluated properties were determined, and the results obtained for houses and land dividing walls were compared. This study contributes for the characterization of adobes traditionally used in Aveiro district, and provides reference values that can be considered in rehabilitation processes

A study of the mechanical properties of adobe bricks collected from houses and land dividing walls in Aveiro district, Portugal, representative of existing traditional constructions, was conducted. Cylindrical adobe specimens were subjected to simple compression and splitting tests. From these tests it was possible to evaluate the strength capacity, stiffness and deformation evolution for increasing loading. Correlations between the evaluated properties were determined, and the results obtained for houses and land dividing walls were compared. This study contributes for the characterization of adobes traditionally used in Aveiro district, and provides reference values that can be considered in rehabilitation processes

This work proposes an integrated methodology for the quantification of the risk associated to damage scenarios in water supply networks, based on the theory of vulnerability, with the quantification of the consequences associated to the loss of the network, for each identified scenario. The identification of the vulnerabilities can contribute to make them more robust as well as to reduce the potential impact of a damage scenario for the system’s users, Neste trabalho propõe-se uma metodologia integrada para a quantificação do risco associado a cenários de dano de redes de abastecimento de água, baseada na teoria da vulnerabilidade, com quantificação das consequências associadas às perdas da rede, para cada cenário identificado. A identificação das vulnerabilidades e dos riscos inerentes a este tipo de sistemas poderão contribuir para os tornar mais robustos, melhorando a qualidade do seu funcionamento, e diminuindo o potencial impacto de um cenário de dano nos utilizadores.

En Portugal, sobre todo en la región de Aveiro, las estructuras de fábrica de adobe fueron el sistema constructivo predominante durante la primera mitad del siglo XX. En la actualidad es aún significativo el legado del patrimonio – cerca de 30% de las construcciones existentes – el cual está formado por un conjunto significativo de construcciones de elevado valor histórico y arquitectónico. En las últimas décadas se ha descuidado su rehabilitación, que ha redundado en el estado actual de daño en muchas de estas construcciones, con desfavorables condiciones de seguridad, y en algunos casos comprometiendo su uso. No obstante, en los últimos años, se observa un creciente interés, asociado a factores ambientales, económicos y de salvaguarda del patrimonio, tanto por parte de las administraciones locales como en el ámbito de los inversores privados, por la conservación y rehabilitación de estas construcciones. Ante esta nueva realidad, que pone de manifiesto la necesidad de desarrollar soluciones y técnicas de intervención que permitan, a través de la rehabilitación y/o refuerzo, prolongar la vida útil de estas estructuras, en la Universidad de Aveiro un grupo de investigadores viene desarrollando un trabajo multidisciplinar sobre las construcciones de adobe en Portugal. El objetivo principal del mismo se centra en la creación de una base de resultados experimentales que apoye las intervenciones de rehabilitación y/o refuerzo del patrimonio edificado, y el desarrollo de soluciones de mejora de su comportamiento estructural. Esta investigación se constituye como un guía que procura contribuir al conocimiento de estas fábricas, enfocado sobre todo a la rehabilitación de las mismas, aportando información que permita a los diferentes profesionales que trabajan en este ámbito actuar en la conservación de este patrimonio

En Portugal, sobre todo en la región de Aveiro, las estructuras de fábrica de adobe fueron el sistema constructivo predominante durante la primera mitad del siglo XX. En la actualidad es aún significativo el legado del patrimonio – cerca de 30% de las construcciones existentes – el cual está formado por un conjunto significativo de construcciones de elevado valor histórico y arquitectónico. En las últimas décadas se ha descuidado su rehabilitación, que ha redundado en el estado actual de daño en muchas de estas construcciones, con desfavorables condiciones de seguridad, y en algunos casos comprometiendo su uso. No obstante, en los últimos años, se observa un creciente interés, asociado a factores ambientales, económicos y de salvaguarda del patrimonio, tanto por parte de las administraciones locales como en el ámbito de los inversores privados, por la conservación y rehabilitación de estas construcciones. Ante esta nueva realidad, que pone de manifiesto la necesidad de desarrollar soluciones y técnicas de intervención que permitan, a través de la rehabilitación y/o refuerzo, prolongar la vida útil de estas estructuras, en la Universidad de Aveiro un grupo de investigadores viene desarrollando un trabajo multidisciplinar sobre las construcciones de adobe en Portugal. El objetivo principal del mismo se centra en la creación de una base de resultados experimentales que apoye las intervenciones de rehabilitación y/o refuerzo del patrimonio edificado, y el desarrollo de soluciones de mejora de su comportamiento estructural. Esta investigación se constituye como un guía que procura contribuir al conocimiento de estas fábricas, enfocado sobre todo a la rehabilitación de las mismas, aportando información que permita a los diferentes profesionales que trabajan en este ámbito actuar en la conservación de este patrimonio

This work proposes an integrated methodology for the quantification of the risk associated to damage scenarios in water supply networks, based on the theory of vulnerability, with the quantification of the consequences associated to the loss of the network, for each identified scenario. The identification of the vulnerabilities can contribute to make them more robust as well as to reduce the potential impact of a damage scenario for the system’s users, Neste trabalho propõe-se uma metodologia integrada para a quantificação do risco associado a cenários de dano de redes de abastecimento de água, baseada na teoria da vulnerabilidade, com quantificação das consequências associadas às perdas da rede, para cada cenário identificado. A identificação das vulnerabilidades e dos riscos inerentes a este tipo de sistemas poderão contribuir para os tornar mais robustos, melhorando a qualidade do seu funcionamento, e diminuindo o potencial impacto de um cenário de dano nos utilizadores.

Nas últimas décadas, a avaliação do risco sísmico é de preocupação crescente, considerada essencial na actividade e definição de estratégias de planeamento e gestão urbana. A avaliação da vulnerabilidade sísmica dos edifícios existentes na perspectiva da mitigação do risco sísmico deve colocar-se não só em relação aos edifícios isolados de relevante importância histórica, mas também em relação aos aglomerados de construções em centros históricos., In the last decades the evaluation of the seismic risk is, of rising concern, considered essential in the activity and definition of strategy planning and urban management. The evaluation of the seismic vulnerability of the existent building stock in the perspective of the seismic risk mitigation should not be placed only in relation to the isolated buildings of relevant historical importance, but also, in relation to the agglomerate of buildings in historical city centers.

Nas últimas décadas, a avaliação do risco sísmico é de preocupação crescente, considerada essencial na actividade e definição de estratégias de planeamento e gestão urbana. A avaliação da vulnerabilidade sísmica dos edifícios existentes na perspectiva da mitigação do risco sísmico deve colocar-se não só em relação aos edifícios isolados de relevante importância histórica, mas também em relação aos aglomerados de construções em centros históricos., In the last decades the evaluation of the seismic risk is, of rising concern, considered essential in the activity and definition of strategy planning and urban management. The evaluation of the seismic vulnerability of the existent building stock in the perspective of the seismic risk mitigation should not be placed only in relation to the isolated buildings of relevant historical importance, but also, in relation to the agglomerate of buildings in historical city centers.

Adobe is commonly found in Aveiro's ancient constructions. Preservation and rehabilitation of those constructions, some of them with architectural and historical interest, has been forgotten for many years. As a result, in Aveiro region, the majority of existing constructions in adobe is structurally weak, and, in several cases, they are in the threshold of ruin. Rehabilitation and/or strengthening urge. Despite some efforts has been made, a great difficulty for technicians working on the rehabilitation of these constructions relies on the lack of knowledge on adobe's mechanical behaviour. In fact, in order to properly describe the structural behaviour of those constructions, there is a need to investigate the mechanical behaviour of adobe. Hence, this paper is based on a study intended to characterise the behaviour of adobe brick units. Specimens were prepared from selected representative constructions of the Aveiro region. The prepared specimens were tested in order to evaluate their mechanical behaviour in compression and tension

Adobe is commonly found in Aveiro's ancient constructions. Preservation and rehabilitation of those constructions, some of them with architectural and historical interest, has been forgotten for many years. As a result, in Aveiro region, the majority of existing constructions in adobe is structurally weak, and, in several cases, they are in the threshold of ruin. Rehabilitation and/or strengthening urge. Despite some efforts has been made, a great difficulty for technicians working on the rehabilitation of these constructions relies on the lack of knowledge on adobe's mechanical behaviour. In fact, in order to properly describe the structural behaviour of those constructions, there is a need to investigate the mechanical behaviour of adobe. Hence, this paper is based on a study intended to characterise the behaviour of adobe brick units. Specimens were prepared from selected representative constructions of the Aveiro region. The prepared specimens were tested in order to evaluate their mechanical behaviour in compression and tension