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The purpose of this paper is to capture the actual structural behavior of the longest timber footbridge in Spain by means of a multi-scale model updating approach in conjunction with ambient vibration tests.

In a first stage, a numerical pre-test analysis of the full bridge is performed, using standard beam-type finite elements with isotropic material properties. This approach offers a first structural model in which optimal sensor placement (OSP) methodologies are applied to improve the system identification process. In particular, the effective independence (EFI) method is used to determine the optimal locations of a set of sensors. Ambient vibration tests are conducted to determine experimentally the modal characteristics of the structure. The identified modal parameters are compared with those values obtained from this preliminary model. To improve the accuracy of the numerical predictions, the material response is modeled by means of a homogenization-based multi-scale computational approach. In a second stage, the structure is modeled by means of three-dimensional solid elements with the above material definition, capturing realistically the full orthotropic mechanical properties of wood. A genetic algorithm (GA) technique is adopted to calibrate the micromechanical parameters which are either not well-known or susceptible to considerable variations when measured experimentally.

An overall good agreement is found between the results of the updated numerical simulations and the corresponding experimental measurements. The longitudinal and transverse Young's moduli, sliding and rolling shear moduli, density and natural frequencies are computed by the present approach. The obtained results reveal the potential predictive capabilities of the present GA/multi-scale/experimental approach to capture accurately the actual behavior of complex materials and structures.

The uniqueness and importance of this structure leads to an intensive study of its structural behavior. Ambient vibration tests are carried out under environmental excitation. Extraction of modal parameters is obtained from output-only experimental data. The EFI methodology is applied for the OSP on a large-scale structure. Information coming from several length scales, from sub-micrometer dimensions to macroscopic scales, is included in the material definition. The strong differences found between the stiffness along the longitudinal and transverse directions of wood lumbers are incorporated in the structural model. A multi-scale model updating approach is carried out by means of a GA technique to calibrate the micromechanical parameters which are either not well-known or susceptible to considerable variations when measured experimentally.

This paper presents an overview and discusses the applications of fibre reinforced polymer (FRP) bars as reinforcement in civil engineering structures. Following a discussion of the science underpinning their use, selected case studies where FRP reinforcement has been used are presented. The use of FRP reinforcement is rapidly gaining pace and may replace the traditional steel due to its enhanced properties and cost‐effectiveness. In addition, FRP reinforcement offers an effective solution to the problem of steel durability in aggressive environments and where the magnetic or electrical properties of steel are undesirable.

Timber waste from construction is downcycled into non-structural products, incinerated for energy generation or disposed of in landfills. Existing literature highlights that the use of reprocessed timber for structural purposes is limited. Therefore, this study aims to focus on identifying factors limiting reprocessed structural timber (RST) uptake amongst construction professionals in Australia.

Current literature shows that the use of reprocessed materials (RMs) depends on user-specific personal factors and broader contextual factors. Therefore, data collection and analysis were based on the attitude-behaviour-context (ABC) theory, which affirms this relationship between personal and contextual factors in determining pro-environmental behaviours (PEBs). A qualitative research approach was adopted, considering limitations with industry expertise and the need for developing an in-depth understanding of limiting factors. Twenty semi-structured interviews were conducted amongst construction professionals experienced in using reprocessed materials, while the thematic analysis technique was used to analyse interview findings.

Personal factors that limit the uptake of RST include negative cost and quality perceptions, risk appetite, the tendency to maintain the status-quo, limited decision-making capability and lack of skills and expertise, while contextual factors include higher prices, poor and uncertain quality, limitations with information availability, under-developed supply and drawbacks in the regulatory environment.

The current study is amongst the first to explore the uptake of reprocessed timber for structural uses in Australia. The findings can be utilised to create a stronger demand for RST by directly addressing personal and contextual factors that constrain construction professionals from using RST.

Describes how environmental training is increasingly being recognized as a crucial element of any corporate, environmental strategy. In turn, corporate strategies will be an essential component to the achievement of sustainable development. But how do companies respond to the need to change the everyday practices of staff at all levels? Introduces a three‐layered approach to environmental training. Also examines the evolution and progress of two very different new training products. First, Expert Training Systems plc joined forces with BTCV Enterprises to create a Developing People Programme using the outdoors and incorporating specified environmental projects. More outdoor development suppliers are now offering such packages and they are selling well. Second, Earthwise, produced in 1995 in collaboration with ICI, Sheffield Hallam University and Sanderson CBT, provides an interactive toolkit approach to exploring the environmental aspects of producing a fictitious plastic, “prolene”. The product requires the user to assume a decision‐making role through a matrix of six main issues and 21 sub‐issues. At each sub‐issue there are over 34 events, 200 pieces of advice on offer, over 200 generic principles and around 122 possible courses of action.

The world's first cast iron bridge, which spans the river Severn at Telford in Shropshire, visited by many thousands of visitors from all over the world every year, will have ‘coats of many colours’ this summer. For the first time in twenty years it is being re‐painted at a cost of £100,000. At least, it's thought to be for twenty years because no one can find any trace of when it was actually painted.

An inexorable pursuit of economic gain has ushered in fashionable, entrepreneurial manoeuvres in the arts. This has led not only to the acceptance of new sectoral categories, such as the creative industries, but also to a form of creative industrialization that encourages additive injections of market logic and notions of entrepreneurial value to an erstwhile dependent culture of the arts. Normative silo-based analyses continue unabated in the gnostic worlds of both the arts and entrepreneurship, with a tendency for the latter to ‘rescue’ the ‘failing’ arts. Application of market logic can, however, ignore the multivalence of entrepreneurship or the rich textures of meaning provided by the arts. It is suggested that a consideration of the centrality of imagination offers insights into different forms of value creation in entrepreneurship and of the creative entrepreneurial dimensions in the arts. A review is presented of how entrepreneurship has positioned itself in the arts and questions are raised about the constraints of a market logic approach. It is argued that such an approach promotes a deficit model of the arts and a stagnant, status quo understanding of entrepreneurship. By exploring various arts movements, such as the Bauhaus project, the legacy of Joseph Beuys’s philosophy and the unique, needs-focussed work of the Japanese architect Shigeru Ban, creative latitude can be found in the meaning of entrepreneurship as the mobilization of the resources of imagination.

The purpose of this paper is to present experimental investigations on the structural behaviour of composite sandwich panels for civil engineering applications. The performance of two different core materials – rigid plastic polyurethane (PU) foam and polypropylene (PP) honeycomb – combined with glass fibre reinforced polymer (GFRP) skins, and the effect of using GFRP ribs along the longitudinal edges of the panels were investigated.

The experimental campaign first included flatwise tensile tests on the GFRP skins; edgewise and flatwise compressive tests; flatwise tensile tests on small‐scale sandwich specimens; and shear tests on the core materials. Subsequently, flexural static and dynamic tests were carried out in full‐scale sandwich panels (2.50×0.50×0.10 m³) in order to evaluate their service and failure behaviour. Linear elastic analytical and numerical models of the tested sandwich panels were developed in order to confirm the effects of varying the core material and of introducing GFRP ribs.

Tests confirmed the considerable influence of the core, namely of its stiffness and strength, on the performance of the unstrengthened panels; in addition, tests showed that the introduction of lateral reinforcements significantly increases the stiffness and strength of the panels, with the shear behaviour of strengthened panels being governed by the ribs. The unstrengthened panels collapsed due to core shear failure, while the strengthened panels failed due to face skin delamination followed by crushing of the skins. The models, validated with the experimental results, allowed simulating the serviceability behaviour of the sandwich panels with a good accuracy.

The present study confirmed that composite sandwich panels made of GFRP skins and PU rigid foam or PP honeycomb cores have significant potential for a wide range of structural applications, presenting significant stiffness and strength, particularly when strengthened with lateral GFRP ribs.

ALUMINIUM CENTENARY. A HUNDRED years ago, at the Paris Exposition of 1855, Prof. Ste. Claire Deville exhibited samples of aluminium which he had extracted from clay by a chemical process. It was not until a generation later, in 1886, that the electrolytic process for extracting aluminium from its oxide was patented simultaneously by Charles Martin Hall in America and Paul Hérault in France. Today, using basically that same method of extraction, 30,000 tons a year of pure aluminium are produced in Britain alone at the hydroelectric plant in the Scottish highlands, and world production in 1954 has probably exceeded 3 million tons a year.

Heritage is the latent part of a sustainable built environment. Conservation and preservation of heritage is one of the United Nations' (UN) sustainable development goals. Many social and natural factors seriously threaten heritage structures by deteriorating and damaging the original. Therefore, regular visual inspection of heritage structures is necessary for their conservation and preservation. Conventional inspection practice relies on manual inspection, which takes more time and human resources. The inspection system seeks an innovative approach that should be cheaper, faster, safer and less prone to human error than manual inspection. Therefore, this study aims to develop an automatic system of visual inspection for the built heritage.

The artificial intelligence-based automatic defect detection system is developed using the faster R-CNN (faster region-based convolutional neural network) model of object detection to build an automatic visual inspection system. From the English and Dutch cemeteries of Surat (India), images of heritage structures were captured by digital camera to prepare the image data set. This image data set was used for training, validation and testing to develop the automatic defect detection model. While validating this model, its optimum detection accuracy is recorded as 91.58% to detect three types of defects: “spalling,” “exposed bricks” and “cracks.”

This study develops the model of automatic web-based visual inspection systems for the heritage structures using the faster R-CNN. Then it demonstrates detection of defects of spalling, exposed bricks and cracks existing in the heritage structures. Comparison of conventional (manual) and developed automatic inspection systems reveals that the developed automatic system requires less time and staff. Therefore, the routine inspection can be faster, cheaper, safer and more accurate than the conventional inspection method.

The study presented here can improve inspecting the built heritages by reducing inspection time and cost, eliminating chances of human errors and accidents and having accurate and consistent information. This study attempts to ensure the sustainability of the built heritage.

For ensuring the sustainability of built heritage, this study presents the artificial intelligence-based methodology for the development of an automatic visual inspection system. The automatic web-based visual inspection system for the built heritage has not been reported in previous studies so far.

Traditional “hierarchical” and “network-centric management” approaches often associated with the management of well-defined construction projects lack the adaptability to cope with uncertainty, standardised practices and the required conformance to industry standards. The purpose of this paper is to propose an integrative “holonic” methodology for the management of megaprojects in the construction industry, which incorporates both adaptability and conformance to standards, and to illustrate the associated benefits of such a methodology.

A multi-case study comprising three cases delivered in the USA and Australia, namely the Adelaide Desalination Plant (ADP), the Seattle–Tacoma International Airport, and the Olmsted Locks and Dam Replacement project were utilized to demonstrate the key features of the hierarchical, network-centric and holonic approaches to managing megaprojects.

The case studies demonstrate incorporating the holonic approach into the management of complex construction projects results in increased management effectiveness and project success. The proposed “holonic” methodology provides the potential to efficiently manage megaprojects navigating through high degrees of uncertainty.

The adoption of the holonic view by project management (PM) practitioners will help them manage megaprojects that are characterised by greater complexity. Second, the proposed methodology enables the discipline of PM to evolve in alignment with rapidly unfolding global transformation trends.

This paper demonstrates the application of the “holonic” methodology to the domain of the management of construction megaprojects. Such an approach is needed as construction projects become increasingly more complex across the world due to technological, political and social uncertainties, larger scale, changing environmental and safety regulations, and the growing involvement of human factors germane to this research.