bluuebunny/crossref_metadata_2025 huggingface dataset:
Sustainable personal transport
Authors: Lowson M.
Published: November 2009

Transport by conventional means involves energy use, resource use and emission output which cannot be regarded as sustainable. Current transport is dominated by the car. This provides the flexible personal transport required by modern forms of cities, but is widely recognised as unsustainable. Current public transport is poorly accepted. Unfortunately, analysis also shows that current forms of public transport offer little, or even negative, benefit in sustainability over the car. A new transport system has been devised to meet the need for transport which is both effective and sustainable. ULTra (Urban Light Transport) is an innovative form of Personal Rapid Transit (PRT). In contrast to previous forms of public transport, there is no waiting, no stopping and no transfers within the system. In many circumstances, it can offer better transport than available by other means. ULTra has been designed to demanding sustainability requirements. Typically, ULTra provides a reduction by a factor of 3 in energy use and emissions output over existing forms of transport. ULTra is also complementary to existing forms of transport. By providing a network link to major rail or bus stations, it can improve the attraction of current transport services. Evaluations undertaken for the Department of Transport and supported by recent questionnaire studies, suggest that a comprehensive ULTra system could attract 25–30% of present car drivers. ULTra is now undergoing engineering development funded by the Department of Transport, Local Government and the Regions. Cardiff County Council has received funding commitments from the National Assembly of Wales which will lead to initial implementation of a system by 2005. It is believed that the system offers a new approach to public transport with a real prospect of significant gains in effectiveness and sustainability.
Aspects of children's road crossing behaviour
Authors: Lupton K. , Colwell J. , Bayley M.
Published: November 2009

This paper describes a qualitative study of children's perceptions of safety in the road environment combined with observations of their road crossing behaviour outside schools recorded on video. The results showed that children's main concern was that drivers do not always comply with the children's set of learned rules for crossing the road, and that drivers could not be relied on to stop at designated crossing points. Children sometimes misperceived the functions of engineering measures and our study showed that sometimes they interacted with them in ways that a designer may not have anticipated. In addition, some children's preferred pattern of movement near schools caused them to cross near to, but not on, a designated crossing where they were at greater risk. The choice of crossing point was influenced by perceptions of distance travelled or by social interaction. This paper highlights the need for these factors to be taken into account in the design and placement of road crossing facilities where a high a degree of use by children is anticipated.
Rethinking urban design
Authors: Whitby M.
Published: November 2009

In the UK today we have realised that we have to think again about towns and urban renaissance and this is high on the political agenda, but we are only just beginning to realise that we need to start at the local level and are still searching for the tools to do so. This presents a real challenge for urban design professionals—to make urban space work, for quality-of-life reasons as well as for productivity. This paper discusses these issues, with particular emphasis on new initiatives such as Returning Roads to Residents, Placechecks and Home Zones.
A conceptual framework for the recycling of aggregates and other wastes
Authors: Winter M. G.
Published: November 2009

A conceptual framework for the understanding of recycled aggregate applications is presented. The framework is described in terms of the environmental and economic utility (or value) of the application, and the utility relative to the original application. The determination of utility considers production factors (energy consumption, financial cost, amount of pollution and waste generated) and factors such as the market value of the product and ‘renewability’ of the primary resource. Examples for each category of utility and relative utility are given. Estimates of the level of aggregate recycling at each level of environmental and economic utility in Scotland are given for 1999. These illustrate the use of the framework as an aid to the interpretation of data for the quantities of aggregates recycled. Although the framework was developed specifically for recycled aggregates it is equally applicable to other material categories and examples are given where appropriate, particularly in relation to relative utility. The concept of utility is considered suitable for both project-level comparisons of different applications for recycled aggregates and also for strategic evaluations at a national level. The concept of relative utility is considered suitable for project-level evaluations of recycled aggregate applications, but not for strategic evaluations.
British Waterways' role in flood mitigation and emergency response
Authors: Sim S. , Morgan L. , Leftley D.
Published: November 2009

British Waterways manages a complex network of canals and rivers that are intrinsically linked with the land drainage and river network of the United Kingdom. Like many other organisations, it was severely affected by the floods of 1998 and 2000 which tested its emergency planning to the limit. This paper explains the causes of flooding in the waterway network, the risks this creates and how British Waterways seeks to manage them. Case histories from 1998 and 2000 illustrate the diversity of impacts of flood events and the organisational response to constrain them. It points to the lessons learned from recent events, in particular the need for experienced staff, effective warning and communication systems, and full understanding of how the British Waterways network is integrated linked with the land drainage and new network of the UK.
Urban street tree plantings: identifying the key requirements
Authors: Pauleit S.
Published: November 2009

Trees fulfil important aesthetic, social and environmental functions in urban areas. However, tree life is increasingly under stress, leading to poor vitality and tree decline, particularly in urban streets. The requirements for healthy tree life are broadly known. Criteria for the design of planting sites in streets, choice of tree species and maintenance requirements are outlined in the paper. However, a European survey reveals the wide variance of tree planting and management practice. UK cities and towns performed poorly against criteria such as level of expenditure for trees, street tree quality and site preparation. Evidently, trees are very much undervalued and only an afterthought in the process of planning, design and management of streets. There is an urgent need to develop and apply comprehensive concepts for sustainable urban forests and specifically for street tree plantings. Standards for site planning, as well as increased knowledge of suitable tree species and tree quality standards are key to achieving this goal. Information on best practice needs to be more widely disseminated. The European pilot survey was a first step towards establishing an information network across Europe to collect the information needed for this purpose. There is a need for close collaboration between civil engineers and landscape architects from a very early stage to integrate tree plantings into the design of streets, in order to maximise their benefits and avoid potential conflicts with traffic and utilities.
Social inclusion implications of park-and-ride
Authors: Parkhurst G.
Published: November 2009

Park and ride (P&R) schemes are often promoted as an efficient means of extending the effective catchment of public transport networks into car-dependent areas with low population densities, such as rural districts. However, using P&R typically requires the traveller to have access to a car. As car ownership is often used as an indicator of social inclusion, providing P&R for motorists is not an obvious means of reducing exclusion from travel opportunities. Nonetheless, the present article argues that policies to promote interchange from cars to bus or rail can act as a force for either greater or less social exclusion, depending on who can access the services and what the alternative options would be in the absence of P&R being provided. The conditions under which inclusion is most likely to be promoted are reviewed. Key findings are that P&R facilities should not be developed at the expense of investment in conventional public transport and that the services should not be exclusively aimed at motorists. A particular situation in which motorists on relatively low incomes might benefit from P&R provision is where they would otherwise face high access charges to urban areas, in the form of road tolls or parking fees.
Briefing: Safer travel by design: reducing crime on public transport
Authors: Stafford J.
Published: November 2009

This article explains how careful attention to straightforward design features can make travel safer and reduce levels of crime. It draws conclusions from national initiatives introduced in UK railway and bus systems. A checklist of good practice is included.
Construction safety legislation framework in China
Authors: Fang D. P. , Zhang J. , Vickridge I.
Published: November 2009

China is becoming the largest construction site in the world. Along with the appearance of a large number of fiercely competitive construction companies and the introduction of new construction techniques and materials, personal injury and fatal accidents in construction sites have continued to occur. However, the law regarding construction safety is also changing and improving. This paper on the construction safety legislative framework was prepared with the support of the Ministry of Construction and the State Administration of Working Safety in China. It is based on a comprehensive literature review and in-depth interviews with legislators, government officials and other participants in the construction process. A clear picture of the current situation relating to construction safety legislation in China is presented. After a brief review of the history of construction safety, the newly formed legal framework is described. Several major challenges have been identified and discussed, for example insufficient regulations and codes, poor coordination within and between the ministries and commissions, pervasive corruption. Suggestions are made for the promotion of construction safety in China, including the improvement of the legislative system based on the three principal laws, and the requirement that owners should bear legal responsibilities.
Making Irish roads safer
Authors: Proctor S. , Crowley F.
Published: November 2009

This paper charts the development of road safety engineering in Ireland, from its roots in An Foras Forbartha (The National Institute for Physical Planning and Construction Research) in the mid-1960s, to the partnership arrangements that exist between government and local agencies today. The authors describe the development of local safety schemes, traffic calming and road safety audit, and look towards future developments within the context of Irish road safety targets.
Driver distraction by advertising: genuine risk or urban myth?
Authors: Wallace B.
Published: November 2009

Drivers operate in an increasingly complex visual environment, and yet there has been little recent research on the effects this might have on driving ability and accident rates. This paper is based on research carried out for the Scottish Executive's Central Research Unit on the subject of external-to-vehicle driver distraction. A literature review/meta-analysis was carried out with a view to answering the following questions: is there a serious risk to safe driving caused by features in the external environment, and if there is, what can be done about it? Review of the existing literature suggests that, although the subject is under-researched, there is evidence that in some cases overcomplex visual fields can distract drivers and that it is unlikely that existing guidelines and legislation adequately regulate this. Theoretical explanations for the phenomenon are offered and areas for future research highlighted.
A flood failure flowchart for buildings
Authors: Kelman I. , Spence R.
Published: November 2009

This paper identifies the main pathways by which flood-induced pressure differentials may damage residential properties in England. The process looks beyond slow-rise floods and subsequent damage from water contact in order to consider pressures induced by depth differentials, velocity and waves. A Flood Failure Flowchart is presented which provides first-order insight into the main failure modes which should be quantified in detail. Uncertainties remain due to lack of information and weaknesses in the analysis, particularly the reliance on British Standards which are not currently adequate for designing to mitigate all forms of flood damage. British Standards, possibly in the form of a rating system with guidelines, could nonetheless provide an appropriate mechanism for formalising the vulnerabilities which residential buildings experience from flood pressures. The lack of literature in this area suggests that prior recommendations on flood damage reduction did not necessarily have a strong basis overall because they were bounded to exclude flood-induced pressures. This paper is thus only a first step towards systematically identifying and categorising potential failure modes of residences during floods.
Accountability in the provision of urban services
Authors: Cavill S. , Sohail M.
Published: November 2009

This paper assesses the potential of accountability arrangements to improve the quality of local services as well as the responsiveness of services providers to the needs of users and in particular those of the poor. In the first section of this paper municipal services are embedded in a social and political context, before moving on to explore a broad set of contemporary innovations in the way services are delivered. The research on which this paper is based was undertaken in cities and so specific attention is paid to urban areas. Accountability is defined using the existing literature and the current models for accountability are presented. In the second part of the paper research from case studies in South Africa, Bangladesh and the UK are presented. These studies reveal that while the provision of urban services is often based on ethics—that is, that no one should be disadvantaged by where they live (in the UK) or that everyone should have access to services such as water, sanitation, and electricity (in South Africa)—ethics alone are not enough to ensure adequate urban services. Accountability is most effective when these ethics are translated into more tangible rights or guarantees of performance, which enable ethics to be realised. Increasingly, however, accountability is used to better manage services and their users and has been reduced to a set of technical tools and procedural measures which can be universally applied. Consequently, ethics do not necessarily function as an input to systems of accountability. In conclusion, it is recognised that accountability cannot be reduced to a technocratic, politics-free management tool but are a product of a particular socio-cultural context.
Public toilets: the need for compulsory provision
Authors: Greed C.
Published: November 2009

There is no mandatory requirement for local authorities to provide public toilets. Yet, it is argued, they are a vital component in creating accessible, sustainable and comfortable cities for all. In this paper the reasons for compulsory standards are explained, and the underlying problems of current provision and regulation are investigated. The nature of a spatial toilet strategy in respect of the adequate distribution and location of public toilets is outlined. Changes in the regulatory and organisational aspects of public toilet provision are proposed that would result in a better standard of facilities for twenty-first century needs.
Home Zones—an evolving approach to community streets
Authors: Barrell J. , Whitehouse J.
Published: November 2009

In January 2002, the UK Department for Transport (DfT) announced the 61 schemes that had been successful in sharing a £30 million grant allocation to develop the Home Zone concept throughout England. Eight pilot schemes in England and one in Wales were announced in August 1999 (together with four in Scotland one year later) and the DfT decided that the concept should be extended. Many of the UK's existing residential areas were not designed for the level of traffic, and particularly parking, that now takes place. As a consequence the streets in front of houses have become extended car parks and are perceived as dangerous for children. This has resulted in a breakdown of local communities as families become isolated within their properties. Children particularly are denied the opportunity of playing and mixing with friends in areas that also include traffic. The aim of the Challenge Programme is to develop residential communities where the streets are shared equally between traffic and residents and introduce different uses within the streets—particularly play. An important aspect of the development of these streets is that they should be designed such that vehicle speeds are kept down to between 10 and 15 mph. The local communities should also be actively involved in their design and development. This paper reviews the progress of these schemes to date and examines the various techniques that have been developed to engage the community fully in the design process.
Community involvement in coast protection at Lyme Regis, UK
Authors: Davis G. M. , Cole K.
Published: November 2009

The town of Lyme Regis is located on an unstable and eroding section of the West Dorset coastline in the UK. Such are the threats to the long-term future of the town from continuing instability that West Dorset District Council is promoting the implementation of a series of coast protection schemes to reduce the risk of destructive landsliding and coastal erosion from occurring in the future. The schemes involve major foreshore and slope stabilisation works which impact upon the town's residents and the tourist industry, both in their completed form and in terms of the disruption they may cause during construction. This paper outlines how heavy investment in public consultation by West Dorset District Council and high levels of participation from all interested parties minimises potential conflict and produces a sense of public ownership and a high level of consensus across the town.
Two participatory projects in South Asia
Authors: Tayler K.
Published: November 2009

This paper assesses the experience from two participatory projects in South Asia and concludes that participatory approaches can be severely constrained by institutional factors, including hierarchical systems and attitudes. The adoption of participatory approaches may be a necessary condition for successful projects and programmes but it will rarely be sufficient in itself to guarantee that success. There is a need for renewed attention to the development of professional capacity to first enter into dialogue with community members and then respond to their needs in appropriate ways. Participatory systems that build from local organisations up to the level of a town or city as a whole are conceptually attractive but are likely to prove difficult to implement in practice.
Successful participation methods for local transport planning
Authors: Batheram M. , Hardin J. , Whitfield S.
Published: November 2009

The Local Authorities Local Transport Plan Benchmarking Group was established in 2002 to undertake a continuous process of comparison, review and search for best and better practice within its membership councils. This paper attempts to identify successful participation strategies and techniques used within the benchmarking group that could be deployed by other local authorities in support of the development of their second local transport plan (LTP) for 2006–2011. It is acknowledged that for a transport plan to be successful it requires high-quality public participation and information-gathering techniques to be used to ensure that, as far as practical, the Plan meets local problems and needs.
Reviewing transport governance: the case of Leeds, UK
Authors: English J , Spear J
Published: November 2009

The UK Department for Transport recently announced a range of initiatives to support a more coherent approach to transport planning and delivery in the major urban areas of England. Specifically, the Local Transport Act, which received royal assent in late 2008, enables groups of local authorities and their partners to review their transport governance arrangements and, if appropriate, publish a programme of statutory and non-statutory reforms aimed at improving integration, efficiency and effectiveness of decision making. This paper considers the process of carrying out a governance review in the specific context of Leeds city region. This area comprises 11 local authorities centred on the West Yorkshire conurbation, but also includes parts of North and South Yorkshire, where responsibilities for transport planning, funding and delivery are split across a range of councils, national and regional agencies, as well as multiple public and private sector service providers. The governance review is designed to assess current arrangements, establish whether there is a case for reform and consider reform options to deliver more efficient and effective transport outcomes that support sustainable economic development and quality of life. Options considered include powers for local public transport, rail and highways, governance structures and administrative boundaries, including the transition from West Yorkshire passenger transport authority and executive to a new integrated transport authority. As well as the process of the review itself and some early findings, the paper describes a number of practical, operational and political challenges encountered by those undertaking the review.
Reconsidering privatisation in the governance of water in Spain
Authors: González-Gómez F , Guardiola J , Ruiz-Villaverde A
Published: November 2009

Spain liberalised the governance of municipal services after implementation of law 7/1985 of 2 April 1985, which regulates local government. Since then, many Spanish municipalities have chosen to privatise their urban water service. However, complete privatisation of the water service is now being questioned. The number of water services becoming completely privatised is decreasing and some local governments have changed their initial decisions and reverted to public management. This article explores why privatisation in Spain is being reconsidered. The process of privatisation of water services in Spanish cities and the causes of the re-governance process that some local governments have undertaken are reviewed. With reference to the option of privatisation, different management alternatives chosen by local governments are also considered, as new forms of governance such as mixed public–private partnerships and associationism are steadily acquiring an important role.
Risk and uncertainty in James Bridge remediation
Authors: Turner A. J. , Berwick W.
Published: November 2009

The site of a former copper refinery situated in the Darlaston area of the Black Country in the West Midlands presents a formidable remediation challenge. The site has had a long history of economic exploitation, including mining, brick manufacture and metal refining. At least five mined horizons underlie the site with some 170 possible mine shafts contained within the site boundary. This paper discusses the challenges that this site presents to the procurement process in the selection of an appropriate contract strategy and risk sharing procedures. It is suggested that appropriate remediation can be achieved only by ensuring that risk is allocated equitably and to the party best equipped to manage and mitigate the risk. Risk allocation within the context of procurement is discussed in general and within the context of this particular site.
The behaviour of shear connections in a composite beam with a full-depth precast slab
Authors: Shim C. S. , Kim J. H. , Chang S. P. , Chung C. H.
Published: November 2009

For the design of shear connections with a full-depth precast slab, it is necessary to investigate strength, stiffness, slip capacity and fatigue endurance. For these purposes, push-out tests were performed with variations of the stud shank diameter and the compressive strength of the mortar. From the experimental work, it could be observed that the deformations of the studs in a full-depth precast slab were greater than those in a cast-in-place slab. The static strengths of the shear connections obtained agree approximately with those evaluated from the tensile strength of the stud shear connectors owing to the effect of the bedding layer. An empirical equation for the initial shear stiffness of a shear connection is also proposed. On the basis of the results of push-out tests, a full-scale composite beam with 8·0 m span was designed and fatigue tests were carried out to study the behaviour of the stud shear connection and its effects on the flexural behaviour of the beam. The bonding and friction between the concrete slab and the steel beam considerably increased the fatigue endurance of the shear connection. Discussions about design are also presented.
A refined strut–tie model approach and its application tool
Authors: Yun Y. M.
Published: November 2009

This paper presents a refined strut–tie model approach and its application tool for the analysis and design of structural concrete. In this approach, non-linear techniques are incorporated in the development, analysis and verification processes of a strut–tie model. The additional positioning of concrete ties and steel struts at the locations of steel ties and concrete struts, respectively, is also incorporated. The proposed approach can eliminate the limitations the current strut–tie model approach has in the prediction of the behaviour and strength of structural concrete as well as in the precise design of structural concrete which experiences non-linear behaviour. The interactive computer graphics programme for the refined strut–tie model approach consists of three parts. The first and second parts are considered as the pre- and post-processors for a finite-element analysis of two-dimensional plain concrete and plane truss structures. The third part is a design routine for dimensioning and detailing the components of the developed strut–tie model. The use of the interactive computer graphics programme in the refined strut–tie model approach is illustrated with an example of the analysis of a reinforced concrete deep beam tested to failure. The refined strut–tie model approach with computer graphics capabilities can provide effective and consistent solutions to a large number of complex analysis and design problems.
Web buckling of tapered plate girders
Authors: Mirambell E. , Zárate A. V.
Published: November 2009

When hot rolled beams (cross-section I and H) show insufficient strength or are not economic for design purposes, plate girders are usually designed, in most cases by welding several plates together. More efficient structural elements can often be achieved by designing these plate girders as tapered plate girders. This is usually done by means of a web panel (steel building frames, and steel and composite bridges), the depth of which varies linearly. One of the main distinctive features of tapered plate girders is the considerable slenderness of the web. This often results in web buckling in the elastic range prior to the yielding of the steel. This article presents an analytical formulation that makes it possible to determine the critical shear buckling stress of slender tapered web panels. This formulation, obtained on the basis of numerical studies of plate instability, takes into account the influence of all the geometric design parameters and the presence of the flanges.
Control of reinforcement corrosion by surface treatment of concrete
Authors: Sergi G. , Seneviratne A. M. G. , Maleki M. T. , Sadegzadeh M. , Page C. L.
Published: November 2009

It is known from laboratory studies that reinforcement corrosion in carbonated concrete can be controlled simply by ensuring that the concrete remains relatively dry. An apparently obvious and cost effective way of excluding external moisture from building components which are not exposed to effects of capillary suction from groundwater, etc. is by applying a waterproof coating to the surface of the concrete. A research programme was undertaken for six years, with the primary aim of assessing whether coatings with appropriate characteristics could maintain suitably dry conditions within concrete in real carbonated structures. A secondary aim was to determine whether a similar predicted extension of the service life could be achieved if corrosion of the reinforcement were induced by internal chlorides. It was recognized from the outset that trials on real structures should be planned so that critical questions that determine the feasibility of the protection technique might be answered. This paper gives an account of the procedures adopted to select appropriate reinforced concrete buildings and characterize repetitive components to allow adequate comparison between the treated materials and controls. It also deals with the selection of candidate surface treatments by specialist manufacturers, the application of these materials according to recommended procedures, the implementation of relevant in-situ monitoring techniques and the extraction of small specimens from the structures for parallel laboratory trials. Results showed that an appropriate elastomeric coating with good crack-bridging properties, fairly low adhesion and good resistance to weathering can maintain a coherent crack-free covering that excludes external moisture and controls the corrosion rate of the reinforcement in carbonated concrete at acceptable levels over a period of at least five years. When corrosion was caused by internal chlorides, however, the concrete could not be maintained in a sufficiently dry condition to provide adequate long term protection to the steel.
Thermal behaviour of composite box-girder bridges
Authors: Chang S. P. , Im C. K.
Published: November 2009

This paper investigates the behaviour of composite box-girder bridges subject to environmental thermal effects such as solar radiation, air temperature and wind speed. It is based on the statistical analysis of measured temperature data which were recorded hourly in a newly constructed composite box-girder bridge for about 20 months continuously. Major thermal loading parameters that characterize the temperature profile are defined, and the seasonal behaviour of the parameters is described in detail. The experimental results are compared to the specifications suggested in the design codes for thermal loads. In addition, a series of heat transfer analyses using the two-dimensional finite element method is conducted in order to generalize the results to bridges with different cross-sections. The findings of this study show that the design temperature distribution with uniform differential between the concrete slab and the steel girder is unsuitable for representing the thermal effects in design purpose.
Experiments on composite steel beams with precast concrete hollow core floor slabs
Authors: Lam D. , Elliott K. S. , Nethercot D. A.
Published: November 2009

Precast concrete hollow core floor units are frequently used in multistorey steel-framed buildings where they bear on to the top flanges of universal beams. The steel beam is normally designed in bending in isolation from the concrete slab and no account is taken of the composite beam action available with the precast units. Although some commercial data are available, there is no general design guidance to cover the wide range of material and geometric variables found in this form of construction. This paper summarizes research carried out at the University of Nottingham on this form of construction and presents the results of three full-scale bending tests of steel beams acting compositely with proprietary precast hollow core slabs. The 150 mm deep units were attached to the universal beams through 19 mm diameter headed shear studs, and tested in four-point bending over a span of 6 m. For typical geometry and serial sizes the composite beams were found to be twice as strong and nearly three times as stiff as the equivalent isolated steel beams. The failure mode was ductile, and may be controlled by the correct use of small quantities of tie steel and in situ infill concrete placed between the precast units. To generalize the findings, isolated push-off tests and eccentric compression tests were used to study the horizontal interface shear resistance of the headed studs and the strength of the slab, respectively.
Designing composite steel beams with precast concrete hollow-core slabs
Authors: Lam D. , Elliott K. S. , Nethercot D. A.
Published: November 2009

This paper presents a design procedure for steel beams acting compositely with proprietary precast hollow-core slabs. It also contains selected underpinning theoretical analyses that illustrate the rationale behind the design formulae and recommendations. Numerical results for the transfer of horizontal compressive forces through the numerous interfaces and through the load–slip characteristics of the shear studs are presented, i.e. the interfaces between the precast slab and in situ concrete infill, and the in situ infill and steel beam. A method for designing composite beams, including the effective breadth of the precast slab, the degree of shear interaction and prediction of the moment capacity, is given. Load against span graphs for composite beams are provided for use in initial design. A worked example based on the procedures illustrates their application in practice.
Effective lengths of concrete-filled steel square hollow sections in fire
Authors: Bailey Colin
Published: November 2009

Current fire design to the Eurocodes allows the effective length of concrete-filled steel hollow-section columns, in braced multistorey buildings, to be taken as 0·7 or 0·5 times the system length of the column, depending on whether the column is continuous at one or both ends. In the case where the column is continuous at both ends, numerical analyses presented in this paper show that, provided local buckling does not occur, an effective length of 0·55 can be assumed. However, observations from tests on isolated members suggest that local buckling generally occurs at the top of heated concrete-filled columns. This is caused by differential thermal expansion, where the expansion of the steel shell is greater than that of the concrete core. This differential expansion causes the steel shell to support the applied load, which, due to loss of strength as its temperature rises, will buckle locally, with the load being redirected back to the concrete core. The analyses showed that if the effects of local buckling were included, the effective length of columns in fire was increased to a value of 0·75. It is recommended that this value should be used in design. Analyses were also conducted on columns that were continuous at one end. These indicated that a value of 0·8 times the system length should be used in design, if the column is continuous at its base. If an idealized-pinned foundation is assumed, the effective length should be taken as the system length.
Continuous precast concrete girder and slab bridge decks
Authors: Marí A. R. , Montaner J.
Published: November 2009

The availability of powerful means of lifting and transportation, high-performance building materials and refined structural analysis methods, along with the use in the same structure of pretensioning, post-tensioning, prefabrication and in situ construction techniques, has led to considerable changes in the design and construction of concrete bridges. Such advances allow engineers to design and build, for example, continuous precast concrete girder bridges, constant or variable in depth and curved or straight in plan, which are comparable to those cast in place, due to their structural efficiency, aesthetic appearance and economical competitiveness. This paper describes the geometric characteristics, conceptual design, analysis and construction of a new type of continuous precast concrete girder bridge. A typical bridge consists of precast prestressed concrete beams with a U cross-section, monolithically interconnected by post-tensioning of the end diaphragms. A cast-in-place reinforced concrete slab, positioned on top, provides longitudinal continuity and shapes the box section with side cantilevers. Particular aspects related to the influence of the segmental construction on the structural behaviour at service of these bridges are discussed. Finally, some actual bridges are presented along with proposals for future applications to long-span bridges.
Membrane action in plain concrete slabs under concentrated loading
Authors: Eyre J. R.
Published: November 2009

In certain circumstances, the elimination of steel bar reinforcement from concrete slab construction is made possible by the presence of compressive membrane action. Design practice cannot conveniently take advantage of this, because rigorous strength calculations are not straightforward. A direct method of calculating, by hand, a suitable load capacity has been developed which provides a load improvement factor to be applied to the pure flexure ultimate load. Such a method is unsatisfactory for plain (i.e. unreinforced) concrete slabs. This paper shows how the method can be employed for calculations on plain concrete bridge deck slabs and compares the results with laboratory experiments.
Design procedures for combined shear and patch loading of plate girders
Authors: Roberts T. M. , Shahabian F.
Published: November 2009

A series of tests has been conducted on twelve short-span slender-plate girders to investigate their ultimate resistance to shear loading, patch loading and combined shear and patch loading. Theoretical predictions of ultimate shear and patch resistance, based on existing ultimate-limit-state theories, show reasonably close correlation with the test data presented herein. However, existing interaction formulae, based on tests on trapezoidal beams and plate girders with corrugated webs, appear either unduly conservative or unsafe, while design recommendations in codes of practice appear inconsistent and very conservative. An improved design procedure for slender plate girders subjected to combined shear and patch loading is presented, the results of which show satisfactory correlation with the available test data.
Peeling failure of reinforced concrete beams with fibre-reinforced plastic or steel plates glued to their soffits
Authors: Raoof M. , Hassanen M. A. H.
Published: November 2009

In recent publications by the first author and his associates, a theoretical model (backed by extensive test data by others) for premature plate peeling failures of reinforced concrete beams strengthened in flexure by gluing steel plates to their tension sides was reported. The primary purpose of the present paper is to extend this theoretical model to cases where fibre-reinforced plastic (FRP) (as opposed to steel) plates are used for upgrading reinforced concrete beams in flexure. As in the case of steel, due to large variations in the spacings of stabilized cracks within the concrete cover zone (by a factor of, say, 2) a unique solution for the FRP plate peeling load does not exist, and one needs to resort to theoretical upper/lower bounds, with the lower bound being the appropriate one for design purposes. For steel plates, a simple preliminary design approach is to keep the plate width to thickness ratio above 60. However, no such simple value for the plate width/thickness ratio has been found for externally bonded FRP plates (which, unlike steel plates, are available with a wide range of ultimate strengths and Young's moduli); hence the pressing need for a reliable theoretical model. Finally, with the theoretical predictions for FRP and steel-plated beams backed by nearly 170 (mainly large-scale) test results from a number of independent sources, covering a wide range of beam design parameters, the proposed model is thought to be reliable and generally applicable.
Stadium Australia: for 2000 Olympics
Authors: Morley S. , King A. , Ashfield M.
Published: November 2009

Sydney's successful bid to host the 2000 Olympic Games has resulted in a spectacular Olympic stadium which forms the centre-piece of a coordinated suite of venues. The stadium will provide 115 000 seats during the 2000 Olympics and Paralympics, and a post-games capacity of 80 000. At a cost of A$463 million, the stadium will have a greater seating capacity than any other Olympic stadium ever built. The selection of the development consortium was based on many factors including an inspired financial and operational plan but, above all, a powerful design statement. The stadium will become the model for the next generation of international stadia, its flexible structure allowing multiple sports usage and integrated mass communications. In a subject matter as vast as this, this paper seeks only to present highlights of the structural design aspects; and in particular the inspirational roof of the Olympic stadium, in the context of a fast-track programme which achieved a grand opening in March 1999, some 18 months before the 2000 Olympics.
Prediction of the initial stiffness of ductile end-plate steel connections
Authors: Brown N. D. , Hughes A. F. , Anderson D.
Published: November 2009

Semi-continuous construction is a recognised basis for design of steel structures. Expensive full-strength and rigid joints are avoided, but the frame analysis needs to take account of the expected connection performance. Wind-moment frames are common examples of semi-continuous construction, for which standard end-plate connections have been developed. These are relatively flexible and therefore have significant influence on sway deflections. This paper presents a method to determine easily the stiffness of such connections when one or two bolt-rows are in tension. This provides a basis for determining the sway of an unbraced frame, or estimating the serviceability of a braced one. The proposed method shows good agreement with tests on the standard connections and on similar forms of joint.
Combined axial and flexural strength of profiled composite walls
Authors: Uy B. , Wright H. D. , Bradford M. A.
Published: November 2009

Profiled composite walls are composed of cold-formed profiled steel sheeting which serves as permanent form-work for a reinforced concrete wall. This form of wall construction can provide many benefits when being used in place of infill panels in steel-framed low-rise and multi-storey buildings. In addition to this, these walls can be used in the retrofitting and rehabilitation of existing reinforced concrete or steel structures to increase the lateral stiffness and strength of a building. Strength is of major importance to the successful application of such members and this paper considers an extensive experimental programme undertaken on walls subjected to combined bending and compression. The tests revealed that due to the thin-walled nature of the sheeting, local buckling was significant. These experiments and independent tests were then used successfully to calibrate a numerical model which incorporated the effects of local buckling. Furthermore, a parametric study was undertaken to consider the effects of various international profiles and the effects of local buckling were again found to be the most significant parameter.
Antiseismic structure: damper-equipped elastic frame
Authors: Aguirre M. , Aguirre R.
Published: November 2009

Conventional antiseismic design of reinforced-concrete (RC) building structures admits inelastic behaviour as a necessary condition to meet requirements of strength and damping, as well as initial-cost economy of the structures. This inelastic behaviour eventually translates into structural damage that may be expensive to repair and also cause considerable inconvenience. This work undertakes the design of an antiseismic, damper-equipped, elastic-frame RC building structure on the basis of regulations specified in the Mexico City building code but generic to any code. Maintaining ample strength, the frame of the structure is designed to behave elastically up to the limit of the storey displacements permitted by the building code. Mild steel dampers, incorporated in the structural frame, provide effective damping, as well as stiffness to resist wind forces adequately. Designing the frame exclusively for elastic behaviour is aimed at diminishing the possibility of structural damage under seismic forces, thus enhancing the economic viability of the structure, provided repair-related cost savings during the life cycle of the structure are taken into account.
Arching action in high-strength concrete slabs
Authors: Taylor S. E. , Rankin G. I. B. , Cleland D. J.
Published: November 2009

The corrosion of reinforcement in bridge deck slabs has been the cause of major deterioration and high costs in repair and maintenance. This problem could be overcome by reducing the amount of reinforcement and/or altering the location. This is possible because, in addition to the strength provided by the reinforcement, bridge deck slabs have an inherent strength due to the in-plane arching forces set up as a result of restraint provided by the slab boundary conditions. This is known as arching action or Compressive Membrane Action (CMA). It has been recognised for some time that laterally restrained slabs exhibit strengths far in excess of those predicted by most design codes but the phenomenon has not been recognised by the majority of bridge design engineers. This paper presents the results of laboratory tests on fifteen reinforced concrete slab strips typical of a bridge deck slab and compares them to predicted strengths using the current codes and CMA theory. The tests showed that the strength of laterally restrained slabs is sensitive to both the degree of external lateral restraint and the concrete compressive strength. The tests particularly highlighted the benefits in strength obtained from very high strength concrete slabs. The theory extends the existing knowledge of CMA in slabs with concrete compressive strengths up to 100 N/mm2 and promotes more economical and durable bridge deck construction by utilising the benefits of high strength concrete.