The rhythms of project life: a longitudinal analysis of work hours and work–life experiences in construction

A diary data collection method was used to collect data from project‐based construction workers in a large civil engineering construction project in Melbourne, Australia. Data capturing the number of hours worked, satisfaction with work–life balance and capacity to complete required tasks at work and at home were collected for 21 consecutive weeks. A strong correlation was found between hours worked each week and participants’ work–life experiences. Data were subjected to time series modelling procedures and weekly work hours were found to significantly predict participants’ capacity to complete tasks at work and at home, but not their satisfaction with work–life balance. The impact of work leading up to a major project milestone was found to increase the predictive capacity of the time series models, indicating that project events have a significant impact upon the work–life experiences of project‐based workers. The period of intense work prior to the milestone (the opening of a new ramp on to an operating freeway) contributed significantly to an immediate reduction in capacity to complete tasks at home. Further time series modelling revealed that recovery opportunities associated with workers taking a short, temporary break from work can also contribute to improved work–life balance. It is proposed that construction organizations use the naturally fluctuating workloads implicit in project work to ‘build’ recovery opportunities into project schedules.     

Work–life strategies in the Australian construction industry: Implementation issues in a dynamic project-based work environment

A participatory work–life balance intervention was implemented in a medium-sized construction contracting organization based in Melbourne, Australia. Weekly data capturing the number of hours worked, satisfaction with work–life balance and capacity to complete required tasks at work and at home were collected for 25 consecutive weeks. Data was subjected to time series modeling procedures and weekly work hours were found to significantly predict participants' overall satisfaction with work–life balance, and capacity to complete tasks at work and at home. The occurrence of ‘long weekends’, i.e., a period of three days away from work arising as a result of a public holiday coinciding with a ‘rostered day off’, was also found to predict workers' capacity to complete tasks at home. An evaluation workshop explored workers' experiences of a work–life intervention. Participants' were generally positive about the organization's support of their work–life balance, however areas for improvement were identified, such as the need for better communication of work–life strategies and to address the ‘long hours’ culture within the organization. The research presents a participatory framework for improving the work–life balance of project-based construction workers.     

The knowledge production–regional economic growth complex: a framework and topics for future research

This note presents an introduction and framework for the papers that make up the special issue. In addition, it makes some suggestions for future research.

Producing and experiencing Harlow: neighbourhood units and narratives of New Town life 1947–53

This paper uses the notions of ‘Utopias of escape’ and ‘Utopias of reconstruction’ to help conceptualize the New Town movement and, in particular, the settlement at Harlow, built from 1947 onwards and located 25 miles north‐east of London. The analysis focuses on the neighbourhood unit as the means by which this and other New Towns were built, and centres on the ideological presuppositions of Modern architects and planners intending to shape modern citizens through the architectural designs provided in Harlow. As a counterpoint to this, perspectives provided by residents of these neighbourhood units are analysed alongside the architectural expressions. As such, a complex narrative of space and place is developed, which not only broadens the traditional approach of architectural geography beyond the ideas of architects and planners, but allows a much fuller interpretation of these spaces to be made. The argument focuses on the two schemes designed by Maxwell Fry and Jane Drew in Harlow: those of Tany's Dell and The Chantry housing groups. The paper concludes with some thoughts on the nature of the historiographical narratives written on planning and experiencing New Towns and the potential ambiguity of such (hi)stories.     

Integrating the fragmented regional and subregional socioeconomic forecasting and analysis: a spatial regional econometric input–output framework

This study presents an integrated socioeconomic forecasting and analysis framework: a spatial regional econometric input?Coutput model and its application to the Chicago metropolitan area. The new framework is designed to overcome some limitations of existing models, particularly (1) limited consideration of population?Cemployment interactions and (2) dominance of top-down approach to vertical integration of regional and subregional variables. It captures local and lower level conditions and their effects on macroeconomic variables by using a modified disequilibrium adjustment model that incorporates subregional dynamics into a regional econometric input?Coutput model in a reciprocal, interactive manner, as opposed to a top-down allocation process. The framework also considers both region-wide and subregional level population?Cemployment interactions more systematically. It is demonstrated that the present model can support socioeconomic forecasting and a broad range of analyses, including the examinations of the macroeconomic impacts of local actions.     

Dynamical identification and modelling of steel–concrete composite high-speed railway bridges

In the last few years, the construction of new high-speed (HS) railways across Europe, as well as in many other countries, has required many different bridges and viaducts. Together with classical concrete solutions, new steel–concrete composite typologies have been developed, giving light and cheap structures. Despite these studies and applications, some concerns still remain about the definition of reliable models for the evaluation of their actual dynamical behaviour under HS train passage. In particular, the influence of many structural and non-structural components, such as cross-girders and ballast, are still not well recognised. In this paper, open problems related to the dynamical assessment and modelling of new steel–concrete four-parallel-girder and box-girder solutions are exposed and analysed. A suitable procedure, based on operational modal analysis, model updating and train–bridge interaction analysis is applied to two bridges, recently built in the new Italian HS network, in order to assess and verify their dynamic behaviour under operative conditions.     

Modeling and investigation of elasto-plastic behavior of steel–concrete composite frame systems

This paper presents a mixed finite-element model combining the fibered beam and layered shell elements using the general finite-element program MSC.MARC (2005r2) based on the discussion and comparison of the previous models. The proposed modeling procedure is intended for integrated elasto-plastic analysis of fully connected steel–concrete composite frames subjected to the combined action of gravity and monotonic lateral loads. The model is verified by extensive experiments and examples, and the behavior of composite frames is also investigated intensively. The slab space composite effect and the beam–column semi-rigidity are the two critical factors influencing the structural behavior. These two factors have not been considered simultaneously in some previous models but can be both included in the proposed model. Due to the complex slab space composite effect in composite frames, the previous models with a constant-width effective flange of slab can not trace the actual nonlinear slab behavior, but the proposed model can give accurate results. Since the slip effect between the steel beam and RC slab has negligible influence on the global calculation results of the structural system verified by the calculation examples, the slip effect is neglected in the present study to simplify the modeling procedure and enhance the calculating efficiency. The proposed model possesses good accuracy and broad applicability with simple modeling procedure and high calculation efficiency, and has a great advantage for the large-scale integrated analysis of multistory and high-rise composite frames.     

Analysis of seismically-isolated two-block systems using a multi–rocking-body dynamic model

A novel multibody rocking model is developed to investigate the dynamic response of two stacked rigid blocks placed on a linear base isolation device. The model is used to investigate the dynamic response of a realistic statue-pedestal system subject to pulse-like ground motions. The analysis shows that, in general, base isolation increases the safety level of the rocking system. However, for large period pulses or small size blocks, the isolator can amplify the ground motion, resulting in a lower minimum overturning acceleration than for the nonisolated system. Further, the amplification or shock spectrum of a linear mass-dashpot-spring oscillator, was found to be the reciprocal of the minimum nondimensional overturning acceleration of the investigated rocking system. Novel rocking spectra are obtained by normalizing the frequency of the pulse by the frequency of the isolator. The analysis also demonstrates how the dynamic response of the two stacked blocks is equivalent to that of a single-block configuration coincident with the whole system assumed monolithic or the upper block alone, whichever is more slender.     

Modeling thermal response of steel–concrete floor systems in a furnace

A methodology was developed to predict the thermal exposure from a furnace onto a floor assembly specimen. In furnaces with low conductivity wall linings and gas fired burners with complete combustion, the gas attenuation effects were determined to be small indicating that radiation between surfaces and convection are the dominant modes of heat transfer. This was modeled by assigning the internal furnace wall temperature to the furnace time–temperature exposure and performing a three-dimensional heat transfer analysis on the specimen. The furnace exposure model predicted heat transfer to the specimen surface that was within 5–14% of measured heat fluxes. The proposed furnace exposure methodology was used to predict the temperature rise of steel in a floor assembly where the test specimen can view itself as well as the furnace, making radiation exchange an important aspect of the problem. Predictions were within 5–10% of the measured values, which was within the experimental uncertainty.     

A process–oriented framework to measure development performance and success of megaprojects

The critical role of the front–end development phase for the success of megaprojects is widely acknowledged despite a lack of theorizing and empirical evidence on what constitutes development performance and success and how to measure them. Rational–instrumental conceptualizations focus on identifying a large number of universal success factors that help avoid the pitfalls of megaproject development. However, these approaches neglect the adversarial and contingent nature of megaprojects and the complex dynamic interactions between their multiple facets. As a remedy, to define and measure the performance and success of megaproject development phase, we build a process–oriented framework which focuses on convergence in terms of project representations and stakeholders’ volition. Then, we propose clear definitions of megaproject development performance and success, by attempting to address the ambiguous distinction between the definitions of overall project success and performance, and by suggesting ways in which our results could help set on a more rigorous ground the research on the relation between development phase performance and overall project success.     

Energy-efficient HVAC systems: Simulation–empirical modelling and gradient optimization

This paper addresses the energy saving problem of air-cooled central cooling plant systems using the model-based gradient projection optimization method. Theoretical–empirical system models including mechanistic relations between components are developed for operating variables of the system. Experimental data are collected to model an actual air-cooled mini chiller equipped with a ducted fan-coil unit of an office building located in hot and dry climate conditions. Both inputs and outputs are known and measured from field monitoring in one summer month. The development and algorithm resulting from the gradient projection, implemented on a transient simulation software package, are incorporated to solve the minimization problem of energy consumption and predict the system's optimal set-points under transient conditions. The chilled water temperature, supply air temperature and refrigerant mass flow rate are calculated based on the cooling load and ambient dry-bulb temperature profiles by using the proposed approach. The integrated simulation tool is validated by using a wide range of experimentally collected data from the chiller in operation. Simulation results are provided to show possibility of significant energy savings and comfort enhancement using the proposed strategy.     

Stochastic key sector analysis: an application to a regional input–output framework

Limits on the precision of technical relationships within input–output frameworks have led to the use of stochastic analytical methods. The notion of stochastic analysis is developed in this paper to discern how the inherent imprecision effect, when aggregated data are utilised, affects the concomitant key sector analysis. Through a Monte Carlo based simulation, the stochastic key sector graph is introduced, with numerical expressions defined which quantify the association of the individual sectors to quadrants of the graph. The technical developments are benchmarked on a small problem, before a stochastic key sector analysis on an aggregated regional input–output table is reported. Comparisons are made between results when the aggregation of sectors is not employed. The paper reveals that aggregation in key sector analysis is inevitably a poor idea. However, it is argued that aggregation is often a practical necessity, so quantifying the uncertainty that is attendant on this aggregation is important, with the “association” expressions introduced potentially central to elucidate this uncertainty. The conclusions of this paper suggest that where analysts and decision makers are obliged to aggregate tables for analytical purposes then problems might be mitigated where marginal sectors are treated with care.     

Chemical compositions and source identification of PM₂.₅ aerosols for estimation of a diesel source surrogate

Exposure to traffic-related pollution during childhood has been associated with asthma exacerbation, and asthma incidence. The objective of the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS) is to determine if the development of allergic and respiratory disease is associated with exposure to diesel engine exhaust particles. A detailed receptor model analyses was undertaken by applying positive matrix factorization (PMF) and UNMIX receptor models to two PM_2.5 data sets: one consisting of two carbon fractions and the other of eight temperature-resolved carbon fractions. Based on the source profiles resolved from the analyses, markers of traffic-related air pollution were estimated: the elemental carbon attributed to traffic (ECAT) and elemental carbon attributed to diesel vehicle emission (ECAD).Application of UNMIX to the two data sets generated four source factors: combustion related sulfate, traffic, metal processing and soil/crustal. The PMF application generated six source factors derived from analyzing two carbon fractions and seven factors from temperature-resolved eight carbon fractions. The source factors (with source contribution estimates by mass concentrations in parentheses) are: combustion sulfate (46.8%), vegetative burning (15.8%), secondary sulfate (12.9%), diesel vehicle emission (10.9%), metal processing (7.5%), gasoline vehicle emission (5.6%) and soil/crustal (0.7%). Diesel and gasoline vehicle emission sources were separated using eight temperature-resolved organic and elemental carbon fractions. Application of PMF to both datasets also differentiated the sulfate rich source from the vegetative burning source, which are combined in a single factor by UNMIX modeling. Calculated ECAT and ECAD values at different locations indicated that traffic source impacts depend on factors such as traffic volumes, meteorological parameters, and the mode of vehicle operation apart from the proximity of the sites to highways. The difference in ECAT and ECAD, however, was less than one standard deviation. Thus, a cost benefit consideration should be used when deciding on the benefits of an eight or two carbon approach.     

Fatigue performance and stiffness variation of stud connectors in steel–concrete–steel sandwich systems

In this study, a series of fatigue tests on six nominally identical push-shear specimens is conducted. The test specimens were subjected to an initial quasi-static test, up to a predefined maximum load, followed by a fatigue test to failure. For all the fatigue tests the mean applied load was the same while the load range varied to induce fatigue failure. The push-shear fatigue tests indicated that stiffness of the shear connections is gradually decreased during the test. Overall, the test results revealed that the lifetime of steel–concrete–steel sandwich systems under cycling loads could be predicted beforehand through the evaluation of the stiffness reduction in shear connections.     

Sources of growth and competitiveness of local tourist production systems: an application to Italy (1991–2001)

Local development can assume many forms, depending on the environmental characteristics of places and the way they evolve historically. Tourist resorts are concentrated on space, forming a well-defined geography of local productive systems which show very different growth rates. The aim of this paper is to establish a geography of local tourist production systems in Italy, and to explore their sources of growth and competitiveness. Results suggest that higher levels of growth are not based on natural endowments but on localization economies, especially on the presence of all the phases of a “tourist filière”, a chain of economic activities directly related to tourism production, in the local production system.     

Holistic study of a timber double skin faade: Whole life carbon emissions and structural optimization

The upkeep of existing buildings has a great role to play in reducing the carbon emissions of the built environment. Fac,ade upgrade represents one of the most effective interventions to improve both thermal efficiency and aesthetic appeal of existing buildings. Double Skin Fa c,ades( DSFs) have much to offer due to their use of solar and w ind energy to passively heat and cool indoor spaces,whilst guaranteeing freedom and flexibility in the aesthetic design of the refurbished building. How ever,DSFs also bear an increase in the embodied energy and carbon due to the additional materials required for the extra skin throughout all life cycle stages.In this article,life cycle assessment( LCA) and dynamic energy modelling have been combined through a parametric approach to obtain figures for the w hole-life cycle carbonassessment of 384 different configurations of an innovative,timber-made DSF for UK low-carbon refurbishments. Additionally,the structural design of the fac,ade w as also investigated through a structural optimisation procedure w hich takes into account all relevant loads and ensures minimal use of the structural material.Results show that operational savings outw eigh the embodied impacts and therefore the proposed DSF is a viable and effective solution for net carbon-negative refurbishments. The operational energy modelling also contributes to the characterisation of DSFs thermal behaviour in temperate climates.     

Gordon Culham: living a ‘useful life’ through the professionalization of Canadian town planning and landscape architecture

Gordon Joseph Culham (1891–1979), a landscape architect and town planner, was instrumental in the professionalization of both his disciplines in Canada. He helped lead the disorganized practitioners of the 1930s into the modern age and enabled them to assume their professional role in the improvement of Canada's urban centres. The discovery of an archive of Culham's papers provides a previously unavailable insight into the conceptualization and creation of the professions of landscape architecture and town planning in Canada. Culham characterized this as leading a ‘useful life’. He prepared, practiced and enjoyed the power associated with the professions he helped found in leading this useful life. He was a Harvard graduate who worked with the greatest landscape architectural firm in America, the Olmsteds and with the premier British town planner, Thomas Adams. Culham returned to his homeland on the eve of the Depression with an unrivalled reputation. He brought with him a strong sense of professionalism and helped elevate a small, dispirited community of Canadian landscape architects and town planners into one united organization for almost two decades. Professional specialization was an inevitable outcome but Culham continued to bridge the divide between his chosen fields throughout his ‘useful life’.     

A new kind of production and value-added multiplier for assessing the scale and structure effects of demand shocks in input–output frameworks

The main purpose of this paper is to develop a new kind of input?Coutput multiplier that would be particularly well suited to quantifying the impacts of final demand changes on the sectoral output or value-added growth potential of an economy. Instead of using the traditional output multipliers, solving an appropriate optimization problem provides what can be called input?Coutput Euclidean distance multipliers. The method does not impose unitary final demand shocks with a fixed (predetermined) sectoral structure, thus allowing the economy to change across the spectrum of all possible final demand variations represented by vectors of modulus 1. It can be very helpful in measuring interindustry linkages and key sectors in a national or regional economy. An empirical illustration is made, using national (Spain and Portugal) and regional (Balearic Islands and the Azores) input?Coutput data.     

News from the field: ‘Town and townscape: the work and life of Thomas Sharp’

The New South Wales Environmental Planning and Assessment Act, 1979, came into effect on 1 September 1980. It was Australia's first planning legislation where the objects of the Act explicitly included a balance between economic, social and environmental outcomes. The Act also facilitated public participation at all stages of plan-making and land-use decision-making. While the Act continues to promote such aims, it has also undergone significant amendment, particularly in the last 5 years. This has seen a distinct move away from the spirit of the original objects of the Act to more centralized and less participatory decision-making. This paper examines the evolution of the Act and of the New South Wales planning system. The NSW Planning Department considers that the state's planning system is still world standard. This review concludes otherwise. Rather, the evidence strongly indicates that a review of the planning system and legislative framework is warranted in order to achieve better land management.     

Australian natural resources law and the Gordon‐Franklin dam controversy: a resource economic analysis

This paper identifies and discusses, within a resource economics perspective, some of the most important legal dimensions of the Gordon‐Franklin dam controversy in Australia. This analysis demonstrates the existence of specific shortcomings in the Australian natural resources legislation. Three basic changes in this legislation are proposed to palliate these shortcomings. These are: (i) the requirement that natural resource use decisions be based on a systematic decision‐making procedure, the specifics of which are presented in the paper; (ii) the opening up of these decisions to the process of judicial review; and (iii) the extension of locus standi rules to individuals or groups who do not have a proprietary interest in a natural resource case. It is shown that these changes would provide a framework for the peaceful resolution of other natural resource conflicts in Australia.