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This paper presents an overview of a process of optimizing concrete mixture for tall buildings, culminating in the design of the Iconic Tower, the key component of the Central Business District of the New Administrative Capital of Egypt. The structural behavior of 76 high-rise towers was compiled and analyzed. A relationship was established between the total concrete thickness for both horizontal and vertical elements and the tower height. The formulae can be used to estimate the total concrete cost of the towers at preliminary and concept stages with sufficient accuracy. The across-wind accelerations for different towers were calculated as per National Building Code of Canada (NBCC) 2005 requirements and compared to measured wind tunnel accelerations. The results showed that code provisions overestimated the measured accelerations by around 60 percent. [ABSTRACT FROM AUTHOR]

The aim of this paper is to review trends in the teaching of posterior composites in the United States, Canada, Ireland, and the United Kingdom over the last fifteen years. The authors compared the results of surveys of the teaching of posterior composites performed in 1989, 1997, and 2004-05. Historical and contemporary international trends were investigated. The amount of clinical and didactic teaching of posterior composites has increased over the past fifteen years. From a time over fifteen years ago, when very few dental students placed posterior composites in dental school, approximately one-third of posterior plastic restorations placed by U.S., Irish, and UK dental students are now composite, with the corresponding finding for Canadian dental schools being approximately 50 percent. Some variations were noted between dental schools in terms of the teaching of contraindications to placement as well as lining and basing techniques. There was some inappropriate teaching of techniques, in particular, in relation to the use of transparent matrix bands and light transmitting wedges. There was also evidence of limited student exposure to newer forms of technology, notably LED curing light units. There have been clear increases in the teaching of posterior composites in the United States, Canada, the United Kingdom, and Ireland in recent years; however, the proportion of posterior composite restorations placed by dental students relative to dental amalgams does not yet match the typical situation in contemporary clinical practice. Dental schools have a responsibility to ensure that their curricula are evidence-based to best prepare their students to meet the needs and expectations of their future patients. [ABSTRACT FROM AUTHOR]

Abstract: An extensive research project is currently being carried out at the University of Manitoba, Canada, involving the development of glass fiber-reinforced polymer (GFRP) wind turbine towers. The towers consist of multi-cell segments, each segment constructed from eight filament wound cells jointed together with resin applied over their interface. The present paper mainly addresses the static and dynamic characteristics, such as failure static loads, modes of failure, fundamental frequencies and periods of such segmented composite towers. Both experimental and numerical results are presented. The experimental investigation involved the testing of two jointed scaled towers. These specimens had a total height of 4.88-m (16-ft) and were tested as cantilevers under static and dynamic loading. The testing was conducted at the W.R. McQuade Structural Engineering Laboratory of the University of Manitoba. Finally, finite element models were developed to analyze the structural behavior, static and dynamic, of single and multi-cell composite segments and towers. The results from the finite element models under static loading were validated through comparison with the experimental results. [Copyright &y& Elsevier]

• Efficiency of GFRP bars in soft-eyes under different load conditions. • Developing design methodology for GFRP RC soft-eyes under different load conditions. • Case study and field applications of GFRP RC soft-eyes. The use of fiber-reinforced polymer (FRP)-reinforced concrete (RC) soft-eyes in tunnel constructions has been gaining noticeable popularity as a successful and practical application of the non-corrosive FRP reinforcement. This unique use of FRP bars takes advantage of their anisotropic property, meaning they are strong along the main axis but can be machined, abraded away, or consumed by tunnel boring machines (TBMs). Consequently, the research program herein offers an inclusive experimental database followed by a detailed theoretical analysis and design provisions for FRP-RC soft-eyes subjected to either axial, flexural, combined axial and flexural loads, or shear stresses. The experimental evidence from our study accentuated the feasibility of FRP reinforcement to maintain strength and stability of FRP-RC elements against all various applied loads. In addition, this paper provides a summary of three field applications of FRP-RC soft-eyes in tunnel constructions located in Canada, highlighting the details of FRP reinforcement, material characteristics, project location, design considerations, and construction methods. The significant field experience herein demonstrated that no major problems or any unanticipated performance-associated troubles were monitored during the construction and service phases. [ABSTRACT FROM AUTHOR]