Tensile behaviour of anchored blind bolts in concrete filled square hollow sections

In this paper, the tensile behaviour of a new type of blind bolt, the anchored blind bolt, has been studied. This type of bolt consists of a conventional blind bolt with a headed stud extension that anchors it into the infill concrete. It has been developed for use in moment-resisting connections between I-beams and concrete-filled hollow section columns. The behaviour of these connections is highly dependent on the tensile behaviour of the anchored blind bolts. Hence, the fundamental mechanics of this behaviour has been studied here, both experimentally and in simulations using FE models. The complex interactions between the headed stud anchorage, the concrete infill, and the steel tube have been examined in detail. The experimental and numerical findings were used to understand the influence of important parameters in the tensile behaviour of the anchored blind bolts. It was found that the location of the bolt with respect to the side walls of the tube had a substantial influence on the behaviour of the anchored blind bolts. All the bolts located close to the side walls of the square hollow sections reached the ultimate tensile capacity of the equivalent structural bolts. This was due to the development of a concrete strut which transferred the load to the corner of the steel section. The bolt diameter also had a significant influence on the stiffness and strength of the anchored blind bolts.     

Electrostatic Control of Structure in Self‐Assembled Membranes

Self‐assembling peptide amphiphiles (PAs) can form hierarchically ordered membranes when brought in contact with aqueous polyelectrolytes of the opposite charge by rapidly creating a diffusion barrier composed of filamentous nanostructures parallel to the plane of the incipient membrane. Following this event, osmotic forces and charge complexation template nanofiber growth perpendicular to the plane of the membrane in a dynamic self‐assembly process. In this work, we show that this hierarchical structure requires massive interfacial aggregation of PA molecules, suggesting the importance of rapid diffusion barrier formation. Strong PA aggregation is induced here through the use of heparin‐binding PAs with heparin and also with polyelectrolytes of varying charge density. Small angle X‐ray scattering shows that in the case of weak PA‐polyelectrolyte interaction, membranes formed display a cubic phase ordering on the nanoscale that likely results from clusters of PA nanostructures surrounded by polyelectrolyte chains.     

Frequency-reconfigurable antennas for multiradio wireless platforms

Looking to increase the functionality of current wireless platforms and to improve their quality of service, we have explored the merits of using frequency-reconfigurable antennas as an alternative for multiband antennas. Our study included an analysis of various reconfigurable and multiband structures such as patches, wires, and combinations. Switches, such as radio-frequency microelectromechanical systems (RFMEMS) and p-i-n diodes, were also studied and directly incorporated onto antenna structures to successfully form frequency-reconfigurable antennas.     

Lewis Base Additives Improve the Zeolite Ferrierite‐Catalyzed Synthesis of Isostearic Acids

Isostearic acids (IA) are highly utilized for industrial purposes especially in the area of biolubricants, such as cosmetics and slip additives for polyolefin and related copolymer films. This study was designed to develop a zeolitic catalysis process for efficient IA production through isomerization of fatty acids. The process utilized zeolite protonated Ferrierite with a small amount of base additive to neutralize (i.e., poison) the acidic sites on the external surfaces of the zeolite particles to prevent side reactions. Of the six base additives examined, the proton sponge combined with the zeolite protonated Ferrierite was found to be the most effective for this isomerization. With only 0.5 wt% proton sponge additive to 5.0 wt% Ferrierite, the dimers were successfully suppressed from 20.6 wt% yield to 2.42 wt% with an IA yield of 83.4 wt% and a 98 % conversion.     

Numerical study on PM10 collection efficiency in a wire-cylinder electrostatic precipitator under multi-field coupling

The PM10 collection efficiency of a wire-cylinder electrostatic precipitator (ESP) was studied by means of a developed mathematical model, including the multi-field coupling between the gas flow field, the particle dynamic field and the electric field, and applying the Deutsch–Anderson Equation. The diffusion charging mechanism was considered due to the diameter range of PM10. The investigated variables were the applied potential, the gas velocity and the particle distribution. Numerical results indicate that the diffusion charging has significant influence on PM10 removal performance and the effect is more obvious with the decreasing diameter, and that the PM10 collection efficiency increases with the increasing applied potential and the increment of collection efficiency is more significant at lower voltage. Moreover, as the gas velocity at inlet decreases, collection efficiency of PM10 will increase. Finally, the overall efficiency increases with increasing the mean diameter of particle distribution. The research results can provide theoretical and technical references for the design of novel ESP aiming at economy and environment protection.     

Are There Counter-Landscapes? On Milk Trestles and Invisible Power Lines

The paper takes its starting point from the duality in the Estonian rural landscape shaped by social practices. On the one hand, the changes and management of landscapes follow a political decision. At the same time, the old patterns of semi-legal activity offer a resistant practice. The study is illustrated with the milk trestle, a now-disappeared symbol of recent history in the Soviet countryside. The milk trestles and their role in Estonian country life are studied from a threefold perspective—their functions, meanings and the values behind this symbol. The article is based on ethnographic field work carried out between the years of 2001 and 2002 and traces the phenomenon of how living landscape transforms into deserted landscape; in other words, how story becomes history. The paper shows how the milk trestle landscape functioned as a prolongation of the former landscape behind the ideological layers of the Soviet landscapes.     

Alternative work schedule interventions in the Australian construction industry: a comparative case study analysis

Project‐based construction workers in the Australian construction industry work long and irregular hours and experience higher levels of work‐to‐family conflict and burnout than office‐based workers, giving rise to an interest in alternative work schedules as a means of supporting work–life balance. Alternative work schedules were implemented in four case study construction projects in Australia. Interventions differed between projects, with two implementing a compressed work week, and the others introducing reduced hours schedules (one of which was optional). Data were collected from each case study project, using various combinations of focus groups, surveys, interviews and daily diary collection methods. The results were mixed. The compressed work week appears to have been favourably received where it was introduced. However, waged workers still expressed concerns about the impact on their weekly ‘take‐home’ pay. Attempts to reduce work hours by changing from a six‐ to a five‐day schedule (without extending the length of the working day between Monday and Friday) were less favourably received. Waged workers, in particular, did not favour reduced hours schedules. The results confirm the existence of two distinct labour markets operating in the Australian construction industry and markedly different responses to alternative work schedules, based upon whether workers are waged or salaried. The results clearly show that attempts to improve work–life balance must take the structural characteristics of the industry's labour markets into consideration in the design of interventions. The impact of alternative work schedules is likely to be moderated by institutional working time regimes within the construction industry.     

Designing for construction workers’ occupational health and safety: a case study of socio-material complexity

Drawing upon an empirical analysis of the design and construction of a food processing facility, a theoretical understanding of the impact of design decision-making on the occupational health and safety (OHS) of construction workers is developed. It is argued that current policy and legislative approaches to Construction Hazard Prevention through Design (CHPtD) are inherently limited because they do not adequately reflect the socio-material complexity of decision-making in construction design. Specifically, the simplistic attribution of responsibility to a single socio-technical actor, ‘the designer’, does not reflect the multiple and disparate influences that impact upon OHS outcomes. Nor do existing CHPtD policy frameworks, management processes and tools recognize the manner in which the interactions and associations between relevant project stakeholders and various non-human artefacts shape (and are also influenced by) the evolution of design decisions. Drawing on actor-network theory (ANT) and using embedded units within a case study approach, the interactions between human actors and non-human artefacts are explored in relation to the design of four components of the food processing facility. The way in which design decisions unfolded and shaped OHS experiences during the construction stage of the project is revealed. The research highlights limitations inherent in current approaches to the management of CHPtD and the need to develop a more robust theoretically based approach to integrating OHS considerations into construction design practice.     

Occupational rehabilitation in the construction industry of Victoria

A survey of construction companies' secondary disability management practices was undertaken in the state of Victoria, Australia. The results indicate that formal rehabilitation and return‐to‐work programmes and practices are not adopted in many companies. Smaller construction firms were less likely to have adopted formal programmes or practices than medium‐to‐large firms. In particular, construction companies reported difficulties in the provision of suitable alternate or light duties for workers returning to work following an injury. Most companies regarded disability management practices to have increased operating costs while yielding little or no benefit in terms of reducing lost workdays. Strategies to overcome some of these impediments to rehabilitation and return‐to‐work in construction are recommended.     

Imagining culture and the city in planning history: some reflections on the public and private

Geography, planning and policy making. P. T. Kivell and J. T. Coppock (eds), GeoBooks, Norwich, 1986. 310 pp, £25.00 $41.25, ISBN 0 86094 211 2

Counterurbanization. International case studies of socio‐economic change in the rural areas. Ronald Perry, Ken Dean and Bryan Brown, GeoBooks, Norwich, 1986. 280 pp, £25.00 $41.25, ISBN 0 86094 205 8

The twentieth century American city: problem, promise, and reality. Jon C. Teaford, Johns Hopkins University Press, Baltimore, 1986. 192 pp, $20.00 cloth ISBN 0 8018 3094 X $8.95 paper ISBN 0 8018 3096 6

San Francisco, 1865–1932: politics, power and urban development. William Issel and Robert W. Cherny, University of California Press, Berkeley, 1986. 294 pp, $35.00, ISBN 0 520 05263 3

The limits of power: great fires and the process of city growth in America. Christine Meisner Rosen, University Press, Cambridge, 1986. 395 pp, £30.00, $39.50, ISBN 0 521 30319 2

Critical issues in urban economic development. Volumes I and II. Victor A. Hausner (ed.), Clarendon Press, Oxford, 1986–7. 235 pp and 207 pp, £22.50 each, ISBN 0 19 823226 7 and ISBN 0 19 823268 3

The elusive city; five centuries of design, ambition and miscalculation. Jonathan Barnett, Harper and Row, New York, 1986. 210 pp, $23.50, ISBN 0 06 430377 2

The conservation of ecosystems and species. Gareth E. Jones, Croom Helm, London, 1987. 277 pp, £27.50, ISBN 0 7099 1463 6

Medicine and industrial society. A history of hospital development in Manchester and its region, 1752–1946. John V. Pickstone, University Press, Manchester, 1985. 369 pp, £35.00, ISBN 0 7190 1809 9

The paradox of professionalism: reform and public service in urban America, 1900–1940. Don S. Kirschner, Greenwood Press, Westport, Conn., Contributions in American History, 119, 1986. 195 pp, $32.95, ISBN 0 313 25345 5

An organisational approach to regional planning. Mario Rui Martins, Gower, Aldershot, 1986. 244 pp, £18.50 ISBN 0 566 00515 8

The tenant movement in New York City, 1904–1984. Ronald Lawson (ed.), Rutgers University Press, New Brunswick, New Jersey, 1986 289 pp, $35.00 cloth $15.00 paper, ISBN 0 8135 1158 5

The Scottish thirties. An architectural introduction. Charles McKean, Scottish Academic Press, Edinburgh, 1987. 200 pp, £17.50 hb ISBN 0 7073 0493 8, £8.50 pb ISBN 0 7073 0493 6

Hikaku Toshi Keikaku Josetsu (Introduction to comparative urban planning; land use controls in Britain and the US). Shun‐ichi Watanabe, Sanseido, Tokyo, 1985. 304 pp, ¥3600, ISBN 4 385 30895 0

Arabic‐Islamic cities. Building and planning principles. Besim Selim Hakim, KPI, London, 1986. 192 pp, £35.00, ISBN 0 7103 0094 8

Imagining tomorrow: history, technology, and the American future. Joseph J. Corn (ed.), MIT Press, Cambridge, Massachusetts, 1986. 237 pp, $17.50 cloth, ISBN 0 262 03115 9