Precast concrete wall-foundation connection. Development of a seismic dissipative connection

Seismic events are a major factor to consider in structural design of buildings in many countries. With the purpose of saving lives, most of the design codes lead to structural solutions that withstand large seismic actions without collapsing, but without taking into account a possible usage of the structures after the earthquake. As a result, it is necessary to consider the time needed to repair/retrofit the damaged structures (i.e. the downtime) since this period of inactivity may result in huge financial implications for the occupants of the buildings. In order to minimise the damages and simplify repair operations, structural solutions with rocking systems and negligible residual displacements have been developed during the last two decades. Systems with precast concrete rocking walls were studied with the aim of investigat- ing suitable and convenient structural alternatives to minimise the damage in case of an earthquake. Experimental, numerical and analytical analyses on post-tensioned solutions, with and without energy dissipation devices, were carried out in this research. The energy dissipation devices were made from steel angles that were further developed during the research. Different solutions for these devices were experimentally tested under cyclic loading and the results are presented. Numerical and analytical work on steel angles was also carried out. Regarding the concrete rocking wall systems, two concrete rocking wall systems were studied: post-tensioned walls and post-tensioned walls with energy dissipation devices. In the latter, the solution was to fix them externally to the wall, allowing their easy replacement after an earthquake. It is shown that the dissipaters are a viable solution for use in precast concrete rocking wall systems. A building case study is presented. The comparison between a traditional monolithic system and a hybrid solution was carried out, allowing the evaluation of the efficiency of the solution that was developed.

Options and Requirements for a potential market entry into Portugal with renewable energy technologies that are applicable for heating and cooling of buildings

NSBE-UNL

Hydroxyapatite porous structures for bone tissue engineering

Esta dissertação teve como objetivo o desenvolvimento de espumas porosas de hidroxiapatite (HA) baseadas em réplicas invertidas de cristais coloidais (ICC) para substituição óssea. Um ICC é uma estrutura tridimensional de elevada porosidade que apresenta uma rede interconectada de poros com elevada uniformidade de tamanhos. Este tipo de arquitetura possibilita uma proliferação celular homogénea e superiores propriedades mecânicas quando comparada com espumas de geometria não uniforme. O cristal coloidal (CC) - o molde da espuma - foi criado por empacotamento de microesferas de poliestireno (270 μm) produzidas por microfluídica e posterior tratamento térmico. O molde foi impregnado com um gel de hidroxiapatite produzido via sol-gel utilizando pentóxido de fósforo e nitrato de cálcio tetrahidratado como percursores de fósforo e cálcio, respectivamente. A espuma cerâmica foi obtida num único passo depois de um tratamento térmico a 1100oC que permitiu a solidificação do gel e a remoção do CC. A análise por espetroscopia de infravermelho por transformada de Fourier (FTIR) e difração de raios-X (XRD) revelou uma hidroxiapatite carbonatada tipo A com presença de fosfatos tricálcicos. As propriedades mecânicas foram avaliadas por testes de compressão. A biocompatibilidade in vitro foi demonstrada através de testes de adesão e proliferação celular de osteoblastos.

Analysis and visualization of energy use for university campus

The reduction of greenhouse gas emissions is one of the big global challenges for the next decades due to its severe impact on the atmosphere that leads to a change in the climate and other environmental factors. One of the main sources of greenhouse gas is energy consumption, therefore a number of initiatives and calls for awareness and sustainability in energy use are issued among different types of institutional and organizations. The European Council adopted in 2007 energy and climate change objectives for 20% improvement until 2020. All European countries are required to use energy with more efficiency. Several steps could be conducted for energy reduction: understanding the buildings behavior through time, revealing the factors that influence the consumption, applying the right measurement for reduction and sustainability, visualizing the hidden connection between our daily habits impacts on the natural world and promoting to more sustainable life. Researchers have suggested that feedback visualization can effectively encourage conservation with energy reduction rate of 18%. Furthermore, researchers have contributed to the identification process of a set of factors which are very likely to influence consumption. Such as occupancy level, occupants behavior, environmental conditions, building thermal envelope, climate zones, etc. Nowadays, the amount of energy consumption at the university campuses are huge and it needs great effort to meet the reduction requested by European Council as well as the cost reduction. Thus, the present study was performed on the university buildings as a use case to: a. Investigate the most dynamic influence factors on energy consumption in campus; b. Implement prediction model for electricity consumption using different techniques, such as the traditional regression way and the alternative machine learning techniques; and c. Assist energy management by providing a real time energy feedback and visualization in campus for more awareness and better decision making. This methodology is implemented to the use case of University Jaume I (UJI), located in Castellon, Spain.

Evaluation of pathogenic fungi occurrence in traumatogenic structures of freshwater fish

INTRODUCTION: Fungal infections in human skin, such as sporotrichosis, can occur after fish induced trauma. This work aimed to identify fungi in freshwater fish that are pathogenic to humans. METHODS: Extraction of dental arches from Serrassalmus maculatus (piranha) and Hoplias malabaricus (wolf fish), stings from Pimelodus maculatus (mandis catfish), dorsal fin rays from Plagioscion spp. (corvina) and Tilapia spp., for culture in Mycosel agar. Some cultures were submitted to DNA extraction for molecular identification by sequencing ITS-5.8S rDNA. RESULTS: Cultures identified most yeast as Candida spp., while sequencing also permitted the identification of Phoma spp. and Yarrowia lipolytica. CONCLUSIONS: While the search for S. schenckii was negative, the presence of fungus of the genera Phoma and Candida revealed the pathogenic potential of this infection route. The genus Phoma is involved in certain forms of phaeohyphomycosis, a subcutaneous mycosis caused by dematiaceous fungi, with reports of infections in human organs and systems. Traumatizing structures of some freshwater fish present pathogenic fungi and this may be an important infection route that must be considered in some regions of Brazil, since there are a large number of a fisherman in constant contact with traumatogenic fish.

Rehabilitation of renders of old buildings in Portugal: survey, supporting methodology proposal and case study

The main purpose of the research is to present a proposal for a methodology to support the rehabilitation project of renders of old buildings in Portugal. To achieve the objective it was considered essential to define the main types of participants and aspects to integrate the proposal. The research methodology consists in an inquiry presented to professional participants in rehabilitation, a market study of materials and products available in Portugal, the design of a methodology proposal and its application to a case study. The inquiry sample totals 24 answers from the targeted professionals. A sequence of relevant supporting procedures consists in the proposal, which aims to provide a supporting methodology to decide and project in this context and also to be tested with its application to the building. This proposal was applied to an old building with load-bearing stone masonry walls and air-lime based renders. It was concluded that the assessment of the building and external renderings’ condition, its diagnosis and of the supporting walls, the definition of intervention, the specification of materials to be used and performance requirements to comply, and also plans for conservation and periodic maintenance, are crucial. From the inquiry, compatibility between materials and complementary roles and points of view of different types of participants in rehabilitation must be highlighted. A proposal for a methodology to support the project could provide useful guidance particularly for architects and construction engineers, and improve the understanding of direct participants on site, therefore contributing for the correct implementation of intervention.

Rehabilitation of renders of old buildings in Portugal: survey, supporting methodology proposal and case studies

The main purpose of the research is to present a proposal for a methodology to support the rehabilitation project of renders of old buildings. To achieve the objective it was considered essential to define the main types of participants and aspects to integrate the proposal. The research methodology consists in an inquiry presented to several professional participants in rehabilitation, a market study of materials and products available in Portugal, the design of a methodology proposal and its application to a case study. The inquiry sample totals 24 answers from the targeted professionals. A sequence of relevant supporting procedures consists in the proposal, which aims to provide a supporting methodology to decide and project in this context and also to be tested with its application to the building. This proposal was applied to an old building with load-bearing stone masonry walls and air-lime based renders. It was concluded that the assessment of the building and external renderings’ condition, its diagnosis and of the supporting walls, the definition of intervention, the specification of materials to be used and performance requirements to comply, and also plans for conservation and periodic maintenance, are crucial. From the inquiry, compatibility between materials and complementary roles and points of view of different types of participants in rehabilitation must be highlighted. A proposal for a methodology to support the project could provide useful guidance particularly for architects and construction engineers, and improve the understanding of direct participants on site, therefore contributing for the correct implementation of the intervention.

Introducing mapping standards in the quality assessment of buildings extracted from very high resolution satellite imagery

Many municipal activities require updated large-scale maps that include both topographic and thematic information. For this purpose, the efficient use of very high spatial resolution (VHR) satellite imagery suggests the development of approaches that enable a timely discrimination, counting and delineation of urban elements according to legal technical specifications and quality standards. Therefore, the nature of this data source and expanding range of applications calls for objective methods and quantitative metrics to assess the quality of the extracted information which go beyond traditional thematic accuracy alone. The present work concerns the development and testing of a new approach for using technical mapping standards in the quality assessment of buildings automatically extracted from VHR satellite imagery. Feature extraction software was employed to map buildings present in a pansharpened QuickBird image of Lisbon. Quality assessment was exhaustive and involved comparisons of extracted features against a reference data set, introducing cartographic constraints from scales 1:1000, 1:5000, and 1:10,000. The spatial data quality elements subject to evaluation were: thematic (attribute) accuracy, completeness, and geometric quality assessed based on planimetric deviation from the reference map. Tests were developed and metrics analyzed considering thresholds and standards for the large mapping scales most frequently used by municipalities. Results show that values for completeness varied with mapping scales and were only slightly superior for scale 1:10,000. Concerning the geometric quality, a large percentage of extracted features met the strict topographic standards of planimetric deviation for scale 1:10,000, while no buildings were compliant with the specification for scale 1:1000.

Minimal computation structures for visual information applications based on printed electronics

In the early nineties, Mark Weiser wrote a series of seminal papers that introduced the concept of Ubiquitous Computing. According to Weiser, computers require too much attention from the user, drawing his focus from the tasks at hand. Instead of being the centre of attention, computers should be so natural that they would vanish into the human environment. Computers become not only truly pervasive but also effectively invisible and unobtrusive to the user. This requires not only for smaller, cheaper and low power consumption computers, but also for equally convenient display solutions that can be harmoniously integrated into our surroundings. With the advent of Printed Electronics, new ways to link the physical and the digital worlds became available. By combining common printing techniques such as inkjet printing with electro-optical functional inks, it is starting to be possible not only to mass-produce extremely thin, flexible and cost effective electronic circuits but also to introduce electronic functionalities into products where it was previously unavailable. Indeed, Printed Electronics is enabling the creation of novel sensing and display elements for interactive devices, free of form factor. At the same time, the rise in the availability and affordability of digital fabrication technologies, namely of 3D printers, to the average consumer is fostering a new industrial (digital) revolution and the democratisation of innovation. Nowadays, end-users are already able to custom design and manufacture on demand their own physical products, according to their own needs. In the future, they will be able to fabricate interactive digital devices with user-specific form and functionality from the comfort of their homes. This thesis explores how task-specific, low computation, interactive devices capable of presenting dynamic visual information can be created using Printed Electronics technologies, whilst following an approach based on the ideals behind Personal Fabrication. Focus is given on the use of printed electrochromic displays as a medium for delivering dynamic digital information. According to the architecture of the displays, several approaches are highlighted and categorised. Furthermore, a pictorial computation model based on extended cellular automata principles is used to programme dynamic simulation models into matrix-based electrochromic displays. Envisaged applications include the modelling of physical, chemical, biological, and environmental phenomena.

The effects of cultural heritage on residential property values: Evidence from Lisbon, Portugal

This paper examines the impact of historic amenities on residential housing prices in the city of Lisbon, Portugal. Our study is directed towards identifying the spatial variation of amenity values for churches, palaces, lithic (stone) architecture and other historic amenities via the housing market, making use of both global and local spatial hedonic models. Our empirical evidence reveals that different types of historic and landmark amenities provide different housing premiums. While having a local non-landmark church within 100 meters increases housing prices by approximately 4.2%, higher concentrations of non-landmark churches within 1000 meters yield negative effects in the order of 0.1% of prices with landmark churches having a greater negative impact around 3.4%. In contrast, higher concentration of both landmark and non-landmark lithic structures positively influence housing prices in the order of 2.9% and 0.7% respectively. Global estimates indicate a negative effect of protected zones, however this significance is lost when accounting for heterogeneity within these areas. We see that the designation of historic zones may counteract negative effects on property values of nearby neglected buildings in historic neighborhoods by setting additional regulations ensuring that dilapidated buildings do not damage the city’s beauty or erode its historic heritage. Further, our results from a geographically weighted regression specification indicate the presence of spatial non-stationarity in the effects of different historic amenities across the city of Lisbon with variation between historic and more modern areas.

Aspectos fundamentais da experiência da vida

A tese que de seguida se esboça assenta sobre uma inquietação fundamental: o facto de cada um dar por si atirado na vida, de, quando cada um dá por si, dar por si a ser vida, etc. Acontece que, logo que se tenta focar mais precisamente de que é de que se trata quando se trata da “vida”, nota-se que esse fenómeno tem habitualmente a forma de um acontecimento anónimo: não se sabe bem a que é que corresponde, que conteúdos tem, que estruturas fundamentais a suportam, etc. Isto é: somos levados pela vida (passamos pela vida, atravessamo-la, estamos expostos a ela, etc.) sem saber exactamente a que é que estamos expostos, o que é que nos leva, sobre que pilares assenta a nossa vivência e a nossa compreensão dela, etc. A tese que se segue não tem a pretensão de deixar definitivamente respondidas estas perguntas; tudo o que faz, na verdade, é meramente proceder a um breve levantamento ou a um registo de algumas das estruturas fundamentais da vida a partir do ângulo da experiência da vida. E, como se espera deixar claro, procurar a resposta a partir do ângulo da experiência (do ângulo da experiência da vida) não é algo acidental ou fortuito. O que se procurará apurar é se não haverá tais laços de afinidade entre “vida” e “experiência” que todas as operações próprias da experiência têm lugar numa vinculação e estão subordinadas às estruturas fundamentais da vida (estruturas que ultrapassam o âmbito da “experiência”) e que, assim também, a vida tenha, de raiz, no modo como nela somos levados e conduzidos, a estrutura ou a forma da “experiência”.

Acellular Gellan-gum based bilayered structures for the regeneration of osteochondral defects: a preclinical study

 In orthopaedics, the management and treatment of osteochondral (OC) defects remains an ongoing clinical challenge. Autologous osteochondral mosaicplasty has been used as a valid option for OC treatments although donor site morbidity remains a source of concern [1]. Engineering a whole structure capable of mimicking different tissues (cartilage and subchondral bone) in an integrated manner could be a possible approach to regenerate OC defects. In our group we have been proposing the use of bilayered structures to regenerate osteochondral defects [2,3]. The present study aims to investigate the pre-clinical performance of bilayered hydrogels and spongy-like hydrogels in in vivo  models (mice and rabbit, respectively), in both subcutaneous and orthotopic models. The bilayered structures were produced from Low Acyl Gellan Gum (LAGG) from Sigma-Aldrich, USA. Cartilage-like layers were obtained from a 2wt% LAGG solution. The bone-like layers were made of 2wt% LAGG with incorporation of hydroxyapatite at 20% and 30% (w/v). Hydrogels and spongy-like were subcutaneouly implanted in mice to evaluate the inflammatory response. Then, OC defects were induced in rabbit knee to create a critical size defect (4 mm diameter and 5 mm depth), and then hydrogels and sponges implanted. Both structures followed different processing methods. The hydrogels were injected allowing in situ  crosslinking. Unlike, the spongy-like were pre-formed by freeze-drying. The studies concerning subcutaneous implantation and critical size OC defect were performed for 2 and 4 weeks time, respectively. Cellular behavior and inflammatory responses were assessed by means of histology staining and biochemical function and matrix deposition by immunohistochemistry. Additionally, both OC structures stability and new cartilage and bone formation were evaluated by using vivo- computed tomography (Scanco 80). The results showed no acute inflammatory response for both approaches. New tissue formation and integration in the adjacent tissues were also observed, which present different characteristic behaviors when comparing hydrogels and sponges response. As future insights, a novel strategy for regeneration of OC defects can be designed encompassing both, hydrogels and spongy-like structures and cellular approaches. References: 1. Espregueira-Mendes J. et al. Osteochondral transplantation using autografts from the upper tibio-fibular joint for the treatment of knee cartilage lesions. Knee Surgery, Sports Traumatology, Arthroscopy 20,1136, 2012. 2. Oliveira JM. et al, Novel hydroxyapatite/chitosan bilayered scaffold for osteochondral tissue-engineering applications: Scaffold design and its performance when seeded with goat bone marrow stromal cells. Biomaterials 27, 6123, 2006. 3. Pereira D R. et al. Gellan Gum-Based Hydrogel Bilayered Scaffolds for Osteochondral Tissue Engineering. Key Engineering Materials 587, 255, 2013.

Proceedings of CMS WORKSHOP: Cracking of massive concrete structures

978-2-35158-155-1