Editorial

Abstract

This issue of Structures and Buildings presents five papers on different scientific topics, ranging from steel structures to reinforced-concrete structures. They shed light on technical problems usually dealt with in current engineering practice.The first paper in this issue, authored by Manis and Bloodworth (2017), assesses the safety of UK transmission tower infrastructure under extreme wind loading. They evaluate the storm magnitudes by applying a change factor methodology to present day wind speeds and using the information provided by the 2009 UK climate change projections. Wind loading on the structure and cables is then determined using Eurocode, and the structure is analysed using pseudo-static finite-element analysis. Fortunately, and despite an estimated increase in wind velocities due to climate change, the typical tower analysed in the study continued to perform satisfactorily at all hazard levels.The second paper by Lawson et al. (2017) addresses the problem of steel-concrete composite beams with low shear connection (interaction) between the beam and slab and presented a design formula to calculate the effective stiffness of composite beams taking account of the stiffness of the shear connectors and their longitudinal spacing. With this formula, the significant additional deflections that occur due to slip in the shear connectors can be accurately calculated. To avoid permanent deformations of the composite beam due to the slip at the serviceability limit state, they propose lower bound limits for the degree of shear connection (30-40%).In the third paper, Johnson et al. (2017) address the analysis and design of tunnel linings of steel fibre reinforced concrete (SFRC). They propose a design method based on principles established by Eurocodes EN 1990 and EN 1992-1-1, EN 14651 and the methodology for SFRC characterisation from the 2010 fib Model Code. Verification methods for both the serviceability limit state and ultimate limit state are discussed and tentative methods of analysis are given, some of which need more test-based evidence. The paper also unveils the areas where stronger evidence from tests and site measurements is needed to enable SFRC tunnel linings to become more economic.The fourth paper in this issue, authored by Sri Rama Chand et al. (2017), presents a study on the behaviour of selfcompacting concrete with recycled aggregates. The compressible packing model, which considers important parameters such as wall effect, loosening effect and perturbed volume, is examined. The authors conclude that this method enables the recycled aggregates to achieve dense matrices in selfcompacting concretes. They also report that because of polydispersal of the mixes, it is possible to minimise the porosity and thus enhance the concrete performance.The fifth paper by Ali et al. (2017) reports a study on the seismic vulnerability of masonry infilled reinforced-concrete frame structures in developing countries. Typical twodimensional reinforced-concrete frames with and without infill panels and with ...