The aim of this work is to study the behaviour of reinforced concrete flat slab structures under combined vertical and horizontal cyclic loading. A total of five specimens were cast and tested: a control specimen was punched without eccentricity, one specimen was tested under constant vertical loading and monotonically increased eccentricity until failure and the remaining three were tested under constant vertical load, at different shear ratios, and cyclic horizontal loading with increasing horizontal drift ratios. All slabs were similar, measuring 4.25×1.85×0.15m3. The reinforced concrete slab specimens were connected to two steel half columns by 0.25×0.25m2 rigid steel plates, prestressed against the slab using steel bolts, to ensure monolithic behaviour. The cyclic tests were performed using an innovative test setup that allows bending moment redistribution, line of inflection mobility, assures equal vertical displacements at the North-South borders and symmetrical shear forces. Results show that cyclic horizontal actions are very harmful to the slab–column connection, resulting in low horizontal drifts and energy dissipation.

Flat slab structures are a very common structural solution nowadays, due to their architectural and economic advantages. However, flat slab-column connections may be vulnerable to punching failure, especially in an event of an earthquake, with potentially high human and economic losses. This type of structural solution is adequately covered by design codes and recommendations in North America, due to a large amount of experimental research carried out. In Europe the situation is different, missing specific guidance to flat slab design under earthquake action in most European codes. The ACI 318-14 prescriptive approach to the gravity shear ratio-drift ratio relationship shows good agreement with experimental results. Following a similar approach and, based in a databank containing cyclic horizontally loaded tests of slab-column connections found in literature, proposals are made applicable to EC2 and MC2010.

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This study focus on the different representations provided by graphing calculators, intending to characterize how the teacher uses and integrates them on the process of teaching and learning functions at the secondary level. The methodology adopted is qualitative and interpretative, undertaking two case studies. The main conclusions point to different levels of flexibility in the use of the different representations depending on the teacher, but suggest a strong preference for the graphical and the algebraic representations, a use of the numerical representation based on the graph of the function and a total lack of use of the tabular representation.

This study focuses on teacher’s Knowledge for Teaching Mathematics with Technology (KTMT), paying a special attention to teacher’s representational fluency. It intends to characterize how the teacher uses and integrates the different representations provided by the graphing calculator on the process of teaching and learning functions at the high school level. Specifically, it intends to understand the balance established between the use of the different representations, and the way these representations are articulated. The study adopts a qualitative approach undertaking one teacher case study. Data were collected for two school years, at 10th and 11th grades, and included class observation, semi-structured interviews and documents gathering. Data analysis was mainly descriptive and interpretive in nature, considering the problem under study. The conclusions reached reveal an active use of the graphical and algebraic representations and a scarce use of the tabular representation. The lack of balance on the use of representations also includes the work within a representation. In this case the graphical representation is the only one that was explored. The conclusions also indicate a flexible articulation between the two representations usually used. It was possible to identify different patterns on the use of the representations and a frequent use of an interactive approach, marked by repeated alternations between representations. Globally, this study emphasizes teacher’s KTMT and raises questions about the impact of technology on teacher´s representational fluency and about the difference between a numerical and a tabular representation.

The teacher’s knowledge has long been viewed as a strong influence on the students’ learning. Several authors have sought to develop procedures to assess this knowledge, but this has proved to be a complex task. In this paper I present an outline of a conceptualization to analyze the teacher's knowledge, based on the model of the Knowledge for Teaching Mathematics with Technology (KTMT) and a set of tasks. These tasks are chosen by the teacher among the ones he prepared for his students taking into account the potential of the tasks to take advantage of the technology’s potential. The analyze of the teacher’s KTMT is based on the characteristics of the tasks chosen by the teacher; the balance established between the representations provided by the technology that the tasks advocate; the way how the tasks pay attention to the new issue of seeking for a suitable viewing window; and also the way how the tasks take into account the expectable difficulties of the students in the process of looking for the window.

The integration of the graphing calculator in mathematical activity encourages students to express many of their processes and ways of thinking. Since some of the activities at the high school level are carried out with the graphing calculator, we intend to investigate the contribution of this resource to promote the learning of nonlinear continuous models in the 11th grade. By adopting a qualitative methodology, we collected and analysed the students‟ writing productions. At first, students used to present the information given by the calculator with no justification. As they acquire skills in the use of this resource, they usually set up the viewing window in order to visualize the graphical representations of functions that model the problem situation they are working on and also relate the different existing menus in the study of those functions characteristics. Such procedures make students to present the data collected in the calculator with a justification of their arguments and a validation of their conjectures.

Computers and technology can play a key role in supporting learning, namely for students with special educational needs. Nevertheless, despite the emphasis the society puts on the use of technology and its fast proliferation in the area of education, few initiatives focus on the specific needs of children with disabilities. Motivated by this gap, this research work proposes a computer assisted education application that targets to teach talking and reading through games. The work described herein was carried out in close cooperation with - , a child-care institution that works with children with distinct growth disorders, namely the Down syndrome.

Abstract This paper reports the first attempt of developing macro-scale auxetic structures based on re-entrant hexagon design from braided composite materials for civil engineering applications. Braided composite rods (BCRs) were produced and arranged as longitudinal and horizontal elements to produce three types of auxetic structures: (1) basic re-entrant hexagon structure, (2) basic structure modified by adding straight longitudinal elements and (3): structure-2 modified by changing structural angle. The influence of various material and structural parameters as well as structure type on Poisson's ratio and tensile properties was thoroughly investigated. The auxetic behaviour was found to strongly depend on the structural angle and straight elements, resulting in lower auxeticity with lower angles and in presence of straight elements. Material parameters influenced the auxetic behaviour to a lesser extent and a decrease in auxetic behaviour was noticed with increase in core fibre linear density and using stiffer fibres such as carbon. The reverse effect was observed in case of tensile strength and work of rupture. Among these structures, structure-3 exhibited good auxetic behaviour, balanced tensile properties, and high energy absorption capacity and their auxetic behaviour could be well predicted with the developed analytical model. Therefore, these novel structures present good potential for strengthening of civil structures.