bluuebunny/crossref_metadata_2025 huggingface dataset:
Carrots and Sticks: Incentives and Regulations for Herbicide Resistance Management and Changing Behavior
Authors: Barrett Michael , Barrett Michael , Soteres John , Shaw David
Published: July 2016

Although the problem of herbicide resistance is not new, the widespread evolution of glyphosate resistance in weed species such as Palmer amaranth (Amaranthus palmeriS. Wats.), common waterhemp (Amaranthus rudisSauer), and kochia [Kochia scoparia(L.) Schrad.] raised awareness throughout the agricultural community of herbicide resistance as a problem. Glyphosate-resistant weeds resulted in the loss of a simple, single herbicide option to control a wide spectrum of weeds that gave efficacious and economical weed management in corn (Zea maysL.), soybean [Glycine max(L.) Merr.], and cotton (Gossypium hirsutumL.) crops engineered for tolerance to this herbicide and planted over widespread areas of the South and Midwest of the United States. Beyond these crops, glyphosate is used for vegetation management in other cropping systems and in noncrop areas across the United States, and resistance to this herbicide threatens its continued utility in all of these situations. This, combined with the development of multiple herbicide-resistant weeds and the lack of commercialization of herbicides with new mechanisms of action over the past years (Duke 2012), caused the weed science community to realize that stewardship of existing herbicide resources, extending their useful life as long as possible, is imperative. Further, while additional herbicide tolerance traits are being incorporated into crops, weed management in these crops will still be based upon using existing, old, herbicide chemistries.
An innovative opening mechanism for a footbridge
Authors: Franck Lee
Published: July 2016

Opening bridges are often the only way of responding to the challenges of construction projects. Some recently built moveable footbridges differ distinctly from conventional solutions, showing that this domain offers possibilities of creative exploration. This paper describes the research and design of an innovative opening mechanism for a long-span footbridge in the port of Ouchy, close to Lausanne in Switzerland. To provide a general overview of existing design solutions, the paper offers a classification of opening mechanisms according to their degrees of freedom. Three innovative opening mechanisms for the given site are proposed and the geometrical parameters that govern the kinematic behaviour for each option are introduced. For the preferred solution, the influence of geometrical parameters on the structural behaviour during opening is analysed and design solutions for structural and non-structural elements are proposed and illustrated. The paper concludes with a description of an experimental demonstration of the proposed mechanism on a reduced-scale model.
Samuel Beckett Bridge, Dublin, Ireland
Authors: Cutter Jerry , Flanagan John W. , Brown Philip , Rando Mario , Mo Gaute
Published: July 2016

The Samuel Beckett Bridge, Dublin City’s newest bridge, is now established as a landmark movable structure spanning the maritime gateway to the city. The bridge is located east of the city’s centre and within the ‘heart’ of the newly developed docklands area, facilitating an important urban transport link for private car use, public transport, cyclists and pedestrians; and contributing towards the improved environmental, commercial and social development of the urban area in which it is located. The bridge is a Calatrava-designed, cable-stayed, steel box girder structure, with a span, across the River Liffey, of 123 m. The bridge, which rotates through 90°, has an asymmetric shape reflecting that of a harp laid on its side, with the base to the cable-stayed steel pylon set outside of the river’s navigational channel – 28 m from the river’s south quay wall. The pylon curves northwards to a point 46 m above the water level with 25 forestay cables set in a ‘harp’ formation. This paper describes the basis of the bridge’s structural and operational design, and the manner in which the main river support was constructed, and the superstructure fabricated and positioned.
Pullout behaviour of deformed steel bars in high-strength recycled aggregate concrete
Authors: John Robert Prince M. , Singh Bhupinder
Published: July 2016

The results of 30 pullout tests carried out on 8-mm and 10-mm dia. deformed steel bars concentrically embedded in high-strength recycled aggregate concrete with coarse recycled concrete aggregate (RCA) replacement levels of 25%, 50%, 75% and 100% are reported. The measured bond–slip relationships indicate similar mechanisms of bond resistance in the RCA and the natural coarse aggregate concretes, and relatively accurate bond strength predictions of the RCA concretes are obtained from a model in the literature. For both the bar sizes, normalised bond strengths of the high-strength RCA concrete – besides being higher than those of the comparable natural coarse aggregate concrete – are observed to increase with an increase in the RCA replacement level. This behaviour is explained in terms of fracture toughness evaluated using an analogous parameter from rock mechanics. An empirical bond stress against slip relationship is proposed and it is conservatively suggested that anchorage lengths of the 8-mm and the 10-mm dia. deformed steel bars in the high-strength RCA concretes of this investigation may be taken as the same as that found in comparable natural aggregate concrete.
Activation of bagasse ash in cement using different techniques
Authors: Noorul Amin  , Sultan Alam
Published: July 2016

This paper reports the results of an investigation, in which bagasse ash was activated using different techniques. Bagasse ash was activated mechanically by grinding to 250, 360 and 420 m2/kg Blaine surface areas, and chemically by mixing bagasse ash with two alkalis, namely potassium hydroxide and sodium hydroxide, at different concentrations. Samples were tested for compressive strength at the ages of 3, 7 and 28 days. Both these methods enhanced the reactivity of bagasse ash. The results indicated that an increase in the fineness of ash resulted in increased strength development and the fineness must be greater than that of the cement to achieve better performance. Alkali activation of bagasse ash led to increased strength development but the strength was lower than that of the control mortar. The test results demonstrate that for high ultimate strength, mechanical activation was more beneficial. Less beneficial effects were found in the case of the chemical activation of the bagasse ash used.
A comparison of 2D and 3D simulations of the River Blackwater
Authors: Barrett Lawrence , Wright Nigel G. , Sterling Mark
Published: July 2016

The present paper reports the findings of a study in which the appropriateness of using two-dimensional (2D) and three-dimensional (3D) numerical modelling in order to simulate the flow in a small reach of the river Blackwater, UK, was examined. The numerical simulations were compared with data obtained from a 1 : 5 scale physical model of the reach. A variety of turbulence models were used in order to evaluate their suitability and assess their impact on the simulations. In order to enable direct comparisons, all of the simulations were undertaken using a single modelling code, Delft3D. It was shown that 3D models offer significant advantages over 2D when applied to a meandering channel and that this choice outweighs the choice of turbulence model.
Lessons from Western Australia's goldfields water supply scheme
Authors: Hartley R. G.
Published: July 2016

In July 1896, the parliament of the sparsely populated colony of Western Australia voted to raise a loan of £2·5 million in London to construct a reliable water supply for its booming Coolgardie goldfield, a sum greater than the total cost of the colony's capital works in any previous year. The scheme, prepared by the colony's engineer-in-chief, Charles O'Connor, involved pumping water 565 km along the world's first steel pipeline, which required 77 000 t of steel plate. This paper argues that the scheme was not one of monumental extravagance as its opponents claimed, but was one that was designed using the latest hydraulic research and ultimately was the only one that could have provided the reliability required to sustain the goldfield past its early years. Logistical problems, both in materials supply and in the construction of the pipeline largely through uninhabited country, were huge by contemporary standards. Two important technical innovations, the locking bar pipe and the mechanical pipe caulking machine, helped keep the cost of the project close to budget. The lessons learnt from the long, but eventually successful, battle against corrosion and leakage benefited hydraulic engineers around the world.
Briefing: Problems and lessons from ageing energy infrastructure
Authors: Hackitt Judith
Published: July 2016

Original assumptions made about facilities and technologies used by the whole range of sub-sectors that make up the energy industry are being put to the test. In land-based storage and manufacturing activities, offshore exploration, production and transportation, many installations are approaching or have already passed their design life. Operators are having to make difficult judgements about whether they can continue operating the plant beyond what had been originally envisaged when it was installed, for how long they can continue and how they decommission when the time comes. Risks associated with all of these options need to be properly managed. This article focuses on the health and safety challenges arising from life extension, with particular attention being given to the process safety and asset integrity management issues that need to be considered to achieve this. By reviewing past events such as the Flixborough and Texas City disasters and analysing the underlying failures that allowed them to happen, the article will translate the broader principles of effective process safety management that have been developed as a result of lessons learnt and set out how they apply to this subject. The article will also give an example of how the UK Health and Safety Executive is approaching this issue by including details of its ongoing work with the offshore oil and gas sector to ensure the continued integrity of North Sea assets in order to ultimately deliver the effective control of risk.
Briefing: Galton on UK railway accidents
Authors: Lane John Stewart
Published: July 2016

Captain Galton's 1862 paper identifies that 116 passengers were killed or injured in UK train accidents between 1854 and 1860, compared with only six passenger fatalities in the most recent comparable period today (2004–2010). When the number of passenger journeys is taken into account (163 435 678 per year in 1860 and 1·4 billion per year in 2010), it may be concluded that British railways today are approximately 170 times safer. Galton provides a detailed analysis of the cause of 534 train accidents that were reported upon by the Board of Trade inspectors. He established that many accidents were due to multiple causes and were preventable in the majority of cases. He found that although there were instances where the cause of the accident was attributable to negligence of railway staff, the main causes were inappropriate methods of working and ineffective management. Galton's recommendations for a safe railway involving greater cooperation between railway companies, the sharing of good practice and learning from accidents are now the reality in today's railways.
Briefing: Engineering Council's guidance on risk
Authors: Bogle David
Published: July 2016

Risk permeates the work of all engineers. This briefing describes the Engineering Council's new guidance for engineers on risk and the thinking behind its development. The guidance on risk was published in March 2011. It comprises a set of six principles, each with supporting statements and exemplars to guide and motivate professional engineers and technicians in identifying, assessing, managing and communicating about risk. The material is generic and profession-wide, and was developed by bringing together expert thinking from across the profession, including civil engineering. It has been welcomed as a milestone in the development of the profession.
The mystery of the partially collapsed Izbor viaduct
Authors: Wojnarski Lukasz
Published: July 2016

On Saturday, 6 May 2006, the launching of the deck superstructure of the Izbor viaduct resulted in the partial collapse of the front section of the launched deck. The construction process of launching the deck was aided by a tower and supporting cable-stayed system. This paper describes the investigation, including on-site material inspections and in-depth analysis, which was carried out to determine the likely cause of the partial collapse. The design and construction deficiencies, which were identified during the assessment of the viaduct, allowed an understanding of the anatomy of the partial failure. Following the investigation, the mystery of the Izbor viaduct was revealed.
Real road load compared to standard load for Brazilian bridges
Authors: Stucchi Fernando Rebouças , Luchi Lorenzo Augusto Ruschi e
Published: July 2016

The first objective of this paper is to compare values of global forces arising from moving loads specified by three international standards on box-girder bridges with different spans and support conditions and try to understand the differences. The second is to present a methodology for the analysis of loads arising from real vehicles over bridges. In the context of the Brazilian reality, the case of a traffic jam is studied. In this methodology a verification model based on the Monte Carlo simulation method is proposed. The data used are related to weighing and the number of vehicles from a highway in the countryside of the state of São Paulo. The third objective is to evaluate the adequacy of the present class 45 standard road load, given by the Brazilian standard (NBR 7188-1984), considering real road traffic and the requirements of the actions and safety standard (NBR 8681-2003). The conclusions are that the Brazilian conditions are different from those prevailing in developed countries, owing to heavier vehicles and traffic jams, and that the standard load is acceptable for two lanes and could be reduced for more lanes. These conclusions were the basis for current revision of the corresponding standard (NBR 7188-1984).
Repairs to electro-slag weld defects on M4 Boston Manor viaduct
Authors: Nicholls Tony , Armstrong Chris , El-Belbol Said , Harrison Jamie , Makinson Neil , Smith David A.
Published: July 2016

Opened in 1965, the 1 km long Boston Manor viaduct carries the M4 motorway into London, UK, and formed part of the London 2012 Olympic route network. A 7·5 t weight restriction was introduced following the discovery of cracks to electro-slag welds in early 2012, after which an emergency solution was needed to remove the restriction in time for the Olympic Games. The extent of the cracks had to be quantified before repairs could begin. With the exception of closing the structure for 6 d to repair a live crack, the solution was implemented with minimal disruption to traffic in just 3 months. This paper describes how the solution was implemented to remove the restriction, enabling the viaduct to remain open for the Games and beyond.
Book review
Authors: Collings David
Published: July 2016

Covered Bridges and the Birth of American Engineering
Characteristics of ‘Gadhi’ soil
Authors: Kondekar Vijay G. , Jaiswal Omprakash R. , Gupta Laxmikant M. , Gandhi Prashant R.
Published: July 2016

‘Gadhi’ is a small hill-sized soil deposit found in the villages of the Maharashtra state of India. The villagers have been using ‘Gadhi’ soil (GS) over many generations for the construction of houses and have found that it offers excellent seasonal comfort, sufficient strength and durability. Native people say that older generations traditionally prepared GS by mixing unknown ingredients in the local black cotton soil (BCS). To obtain an insight into the advantageous properties of GS as a building material, its physical, mineralogical, chemical and dielectric characteristics are studied and compared with those of BCS. GS is a silty soil with medium to high plasticity, and BCS is clay of high plasticity. X-ray diffraction analysis of BCS and GS revealed kaolinite as the principal clay mineral, the crystallinity of GS and the amorphous nature of BCS. X-ray fluorescence spectrometry provided their elemental analysis. Chemical analysis showed the oxide contents, with lower concentrations of iron oxide and higher silica in GS as compared with BCS. Scanning electron microscope analysis of GS was used to study inter-molecular bonding and showed kaolinite sheets on quartz crystals. The dielectric constant of GS revealed its nature as an insulating material. This database will be useful for future studies on correlation analyses between BCS and GS and its stabilisation process.
A review on the buffering capacity of earth building materials
Authors: McGregor Fionn , Heath Andrew , Maskell Daniel , Fabbri Antonin , Morel Jean-Claude
Published: July 2016

Unfired clay building materials are recognised for their ability to regulate indoor humidity levels through their moisture buffering capacity. Research is being conducted on the moisture buffering capacity of a variety of building materials with natural materials, such as clay, and organic materials, such as hemp or straw, presenting a greater potential to regulate indoor humidity than industrial building materials. Due to their high affinity to water, which is usually regarded as detrimental, clay materials present complex hygrothermal coupling phenomena, which are still under investigation. This paper summarises some recent investigations into the dynamic water adsorption process within clay materials in relation to their ability to regulate indoor air humidity levels. First, a review of the experimental methods to characterise this behaviour is provided. A review of experimentally measured results on the material scale using compressed earth block, rammed earth or plaster samples is then provided, followed by some larger and whole building measurements.
Protection against corrosion of reinforcing steel and concrete using polymer–sulfur composites
Authors: Książek Mariusz
Published: July 2016

This paper presents the results of experimental research and analyses indicating the usefulness of special polymer–sulfur composites for the protection of concrete against corrosion. After analysis of the initial results, the optimum compositions were chosen for experimental research. The experimental programme comprised of adhesion of the composite to the standard mortar and concrete, and the loss of the composite or ordinary concrete in acid, alkaline and salt solutions and in water. The corrosivity of different industry environments are varied and certain environments have a more significant impact. Soils with a certain composition, structure and corrosivity, chemical relationships and chemical substances, and particularly the industrial fertiliser- and pesticide-manufacturing environment, are among those with the most significant effect. As far as construction with reinforced concrete is concerned, the corrosivity of an industrial building environment is typically much higher than that of a rural environment, and it may be compared to that of a chemical industry environment. It is affected by humidity and concentration of compounds dissolved in the condensate that increase electrical conductivity and react chemically after they have dissolved in it.
Briefing: Concrete – innovations and practical applications
Authors: Mangabhai Raman , Goodier Chris I. , Trout Edwin , Hewlett Peter , Grantham Michael
Published: July 2016

Concrete is a highly adaptable material and capable of considerable variation, development and innovation, as can be seen from the pages of journals such as the Proceedings of the Institution of Civil Engineers – Construction Materials. This briefing paper describes the 43rd Convention of the Institute of Concrete Technology, which took place on 26 March 2015. The event provided an opportunity for practitioners and researchers to meet and communicate, and to showcase the variety and diversity of current innovations, developments and applications in concrete and cement technology, including carbon-negative aggregate, polycarboxylate ether superplasticisers, waste wood in concrete, steel fibres, calcium aluminate cements, superabsorbent polymers and sprayed concrete tunnel linings.
Strength of cement-stabilised clay by hardness testing
Authors: Wang Zhi-Feng , Chen Yang
Published: July 2016

This paper presents an investigation of the evaluation of the unconfined compressive strength (UCS) of cement-stabilised Shanghai clay by hardness testing. Laboratory tests including the hardness test and the unconfined compression test were carried out. An innovative decision was taken to use the Shore-A durometer to measure the hardness of cement-stabilised clay. Based on the regression analysis of laboratory test results, an exponential equation is proposed to express the unique relationship between the UCS and the degree of hardness. By measuring the hardness of jet grout columns installed in Shanghai clay, the proposed exponential equation was applied as a trial for predicting their UCS. Comparison results suggested that the exponential equation proposed in this study may be used to produce a quick prediction of the UCS by measuring the hardness of samples in the field.
Assessing aggregates for alkali–aggregate reaction potential
Authors: Fernandes Isabel , Andiç-Çakır Özge , Hooton Doug
Published: July 2016

The identification of alkali-reactive aggregates has been a challenge since alkali–aggregate reactions were first diagnosed. Standards, test methods and recommendations have been developed on a local and international basis. The Rilem recommendations regarding alkali–aggregate reactions are based on a methodology in which a series of laboratory tests is suggested. The assessment starts with a petrographic examination of the aggregate, followed by rapid screening tests and concrete expansion tests. This methodology has been carried out by a number of laboratories worldwide. However, some of the tests have not been totally satisfactory as sometimes the results do not correlate with each other or with field performance. A summary of the thresholds, advantages and limitations of each test according to the findings of Rilem TC 219-ACS is presented.
Performance evaluation of polyamine anti-stripping additives
Authors: Imaninasab Reza , Joodaki Sajjad
Published: July 2016

Polyamine anti-stripping additives in asphalt mixes are chemical chains that bond chemically with an acidic siliceous aggregate at one end and an asphalt binder at the other. They help to prevent the hydro-oxide of siliceous aggregates from reacting with water molecules, which can lead to a breakdown of the asphalt mix. The effect of two proprietary polyamine-based anti-strippers, Wetfix and Tackamin-200, on moisture susceptibility, the resilient modulus and rutting performance were evaluated at percentages from 3 to 6% with increments of 0·1%. Wet and dry indirect tensile strength, the indirect tensile resilient modulus and dynamic creep tests were used to assess the moisture susceptibility, structural response and rutting resistance of treated asphalt mixes. The results indicated that 0·5% was the optimum dosage for both additives with respect to all performed tests, with Wetfix being more efficient. Overall, it was found that the impact of the anti-stripping agents on moisture susceptibility was significant.
Rilem activities on alkali–silica reactions: from 1988–2019
Authors: Wigum Børge Johannes , Lindgård Jan , Sims Ian , Nixon Philip
Published: July 2016

Since 1988, the International Union of Laboratories and Experts in Construction Materials, Systems and Structures (Rilem) technical committees (TCs) have been seeking to establish universally applicable test methods for assessing the alkali-reactivity potential of aggregates, and from later on, for concrete mixes. TC 106, in the years 1988 to 2001 focused on accelerated aggregate tests, and presented the findings at the International Conferences on Alkali Aggregate Reactions (ICAAR) in Kyoto in 1989, London in 1992, Melbourne in 1996 and Quebec in 2000. The successor committee TC 191-ARP in the years 2001 to 2006 also included work on diagnosis/appraisal and specification, and presented the findings at the ICAAR in Beijing in 2004. TC 219-ACS in the years 2006 to 2014 introduced work on performance testing and modelling, and presented its findings at the ICAARs in Trondheim in 2008 and in Austin in 2012. The major recommendations were published as a Rilem state-of-the-art report in 2015. In 2014, the TC 258-AAA was established, and it scheduled the completion of work on performance-based assessment for 2019. The preliminary findings will be published at the ICAAR in São Paolo in 2016.
Effects of alkali–aggregate reaction on concrete and structures
Authors: Shayan Ahmad
Published: July 2016

The effects of alkali–aggregate reaction (AAR) on concrete and structures start at the microstructural level, that is, at molecular and microscopic levels, such as the formation of reaction products in  concrete and associated microcracking, which ultimately leads to macro-level effects such as visual cracking, differential movements, displacement and so on. The consequences of these effects are also wide ranging, and depend on the severity of the reaction, the configuration and functions of the affected element and the exposure conditions. The effects of AAR on concrete can range from minor cracking in non-load-bearing elements in benign environments, which may not have any significant consequence, to severe cracking in sensitive structural elements, particularly those exposed to aggressive environments, which could have serious detrimental effects on the mechanical and durability properties of concrete. This paper provides an overview of the changes that occur in the mechanical and durability properties of AAR-affected concrete elements.
Four approaches to determine masonry strength domain
Authors: Milani Gabriele
Published: July 2016

Four models to determine the homogenised strength domain of running bond masonry in-plane loaded are compared. The first is a lower bound, where the elementary cell is subdivided into a few rectangular sub-domains and the micro-stress field is expanded using polynomial expressions. The second is again a lower bound, where joints are reduced to interfaces and bricks are subdivided into constant stress triangular elements. The third procedure is a compatible identification (kinematic approach), where joints are reduced to interfaces and bricks are assumed infinitely resistant. The last model is again a kinematic procedure based on the so-called method of cells. The representative element of volume is subdivided into six rectangular sub-cells with pre-assigned polynomial fields of periodic velocity. The first and latter models have the advantage that the reduction of joints to interfaces is not required. The second approach, albeit reduces joints to interfaces, still allows considering failure inside bricks. The third approach is the most straightforward, but is reliable only for thin joints and strong blocks. Some illustrative examples regarding the determination of masonry homogenised strength domains are discussed, focusing on pros and cons of the models, role played by joint thickness, constituent materials failure surfaces and numerical efficiency.
An upper bound limit analysis formulation for thin plates
Authors: Makrodimopoulos Athanasios
Published: July 2016

In the late 1960s, in the field of upper bound limit analysis of Kirchhoff plates, Hodge and Belytschko suggested the use of an element with quadratic transverse displacements, where the rotations were permitted to be discontinuous. In recent years, various discretisation schemes have been applied making comparisons with the results of that paper. However, 50 years ago, the optimisers were very weak, and could not even take advantage of the convexity of the problem. The aim of this paper is to revisit this rigorous formulation for second-order cone-related yield functions such as Nielsen's and von Mises'. It is shown that with a suitable formulation as a case of second-order cone programming, in the dual static form, the problem can be solved very fast and this simple element provides results that are competitive to those of various other displacement discretisation schemes combined with the same optimiser. Details on how to handle Nielsen's criterion are also given.
Analysis of a thermosyphon using a Mandelstam condition
Authors: Bahrami Fariba , Zarroug Moundheur , Lundberg Peter
Published: July 2016

The characteristics of a thermally forced connected-vessel thermosyphon operating in an oscillatory mode have been determined using analytical techniques, the outcome of which is compared with results obtained by numerical integration of the governing equations. From a previous investigation it was known that adequate phase–plane representations of the limit cycles associated with oscillations could be obtained if the vessel-volume ratio was sufficiently small. This study aims at demonstrating how this constraint on the vessel volumes can be relaxed by prescribing a Mandelstam condition, that is, by postulating that the total heat content of the system remains conserved during the rapid phases of the oscillation. It was concluded that incorporating this Mandelstam condition in the analysis had the highly beneficial consequence that good analytical results could be obtained for much larger values of the vessel-volume ratio than those previously permitted.
A robust method for the simulation of quasi-brittle materials
Authors: Alnaas Waled F. , Jefferson Anthony D.
Published: July 2016

In this paper, the authors describe a number of new acceleration techniques to improve the convergence properties of the recently developed smooth unloading–reloading (SUR) method for the finite-element simulation of quasi-brittle materials. The proposed techniques involve predicting or approximating a damage evolution parameter to simplify the implementation of the SUR algorithm and improve its efficiency in terms of solution time. The latter improvement is illustrated using a series of idealised examples of plain and reinforced concrete sections. The paper also describes a convenient procedure for computing the characteristic length parameter for a range of two-dimensional and three-dimensional finite elements.
Grouted connections on offshore wind turbines: a review
Authors: Tziavos Nikolaos I. , Hemida Hassan , Metje Nicole , Baniotopoulos Charalampos
Published: July 2016

Grouted connections (GCs) have been extensively used in offshore applications over the last decades and are widely used today in offshore monopile wind turbines. The effectiveness of the connections on monopiles was questioned recently after several substructures were reported to have insufficient performance in wind farms over Europe. This paper brings together the current practice in terms of engineering methods used for the determination of loads acting on the structure and the numerical methods used for the investigation of the structural behaviour of the GC. With respect to hydrodynamic loads on monopile wind turbines, the popular linear wave theory along with the Morison equation can be used to model normal sea states, whereas higher-order wave models are necessary to investigate severe events such as wave breaking. In terms of wind loads, blade element momentum proves to be advantageous with respect to computational cost and ease of implementation in simulation tools. Finally, finite-element modelling of GCs is introduced and close attention is given to the non-linearity of the grout material and the interface contact which are considered to be decisive aspects for the structural analysis.
Parsimonious numerical modelling of deep geothermal reservoirs
Authors: Fairs Tim H. , Younger Paul L. , Parkin Geoff
Published: July 2016

Numerical modelling has been undertaken to help improve understanding of a deep geothermal system being considered for development in the vicinity of Eastgate (Weardale, County Durham, UK). A parsimonious numerical modelling approach is used, which allows the possibility to develop a workable formal framework, rigorously testing evolving concepts against data as they become available. The approach used and results presented in this study are valuable as a contribution to a wider understanding of deep geothermal systems. This modelling approach is novel in that it utilises the mass transport code MT3DMS as a surrogate representation for heat transport in mid-enthalpy geothermal systems. A three-dimensional heat transport model was built, based on a relatively simple conceptual model. Results of simulation runs of a geothermal production scenario have positive implications for a working geothermal system at Eastgate. The Eastgate Geothermal Field has significant exploitation potential for combined heat and power purposes; it is anticipated that this site could support several tens of megawatts of heat production for direct use and many megawatts of electrical power using a binary power plant.
Energy harvesting on road pavements: state of the art
Authors: Duarte Francisco , Ferreira Adelino
Published: July 2016

With the growing need for alternative energy sources, research into energy harvesting technologies has increased considerably in recent years. The particular case of energy harvesting on road pavements is a very recent area of research. This paper deals with the development of energy harvesting technologies for road pavements, identifies the technologies that are being studied and developed, examines how such technologies can be divided into different classes and gives a technical analysis and comparison of those technologies, using the results achieved with prototypes.
Air conditioning systems for school buildings: a case study
Authors: Ascione Fabrizio , Bellia Laura , Mele Carlo , Minichiello Francesco
Published: July 2016

Significant attention is currently being paid to reducing building energy demand and improving indoor thermal conditions, as required by European directives. In school buildings, a significant part of the winter energy demand is related to high airflow rates required for ventilating classrooms. Moreover, the correlation between comfortable indoor thermal-hygrometric conditions, healthy indoor air quality and satisfying student performance is well known. Few research works have investigated different types of air conditioning systems for typical school buildings, from the point of view of both energy and thermal-hygrometric performances. This kind of analysis is carried out in this paper. A typical school building located in southern Italy is analysed by using dynamic building energy simulation software. Different types of heating, ventilation and air conditioning (HVAC) systems are simulated for both winter and summer conditions. Indoor air temperature, relative humidity and predicted mean vote values are evaluated. The annual energy requirements, energy costs and related emissions are calculated. Finally, a multi-criteria analysis for the examined HVAC systems is proposed, considering different weighting for the main performance criteria (winter thermal comfort, plant costs, energy costs and emissions), in order to support decision making.
Realising a climate-resilient UK electricity and gas system
Authors: Metz Alexandre , Darch Geoff , Workman Mark
Published: July 2016

The risks presented by climate change mean that there is a need to future-proof the UK's energy (electricity and natural gas) infrastructure. The scale of investment required is estimated at more than £200 billion by 2030. Although there are a variety of funding sources available, increasing proportions of infrastructure investment are now being funded by the private sector. Therefore, it will be necessary to find ways to incentivise private investors to accommodate for adaptation requirements in their decision-making processes. Research was undertaken to explore the UK energy infrastructure under the following three main lenses. (a) What technical aspects of energy infrastructure need to consider the effects of climate change? (b) What investment is required in the near future to adapt to climate change? (c) What types of policy could create reliable signals for investment in climate change adaptation? This paper presents key findings and considerations for policy covering the three questions above: (a) there are data gaps, interdependencies not effectively assessed and techniques available but not yet adopted; (b) the investment community suffers from a lack of climate change expertise and a short-term mindset; and (c) there is a need for a clearer policy vision and greater collaboration.
Governing effective and legitimate smart grid developments
Authors: Langendahl Per-Anders , Cook Matthew , Potter Stephen , Roby Helen , Collins Trevor
Published: July 2016

Smart grids that use information and communication technologies to augment energy network management have been developed in several locations including London and Stockholm. Common rationales for smart grids include: reducing the carbon dioxide emissions of energy supply, maintaining security of supply and promoting affordability. However, beyond these general abstractions, smart grids seem to exhibit considerable diversity in terms of their characteristics and rationales for development. Thus, while the term smart grid may imply abstract notions of what smart grids are and might do, they are developed in response to local contingencies and are diverse. In this paper, the authors therefore explore the governance processes through which smart grids are constructed. The paper suggests that standardising smart grids through definitions and best practices that fix both problems and solutions should be avoided. Rather governance processes should be promoted in which local contingencies can be articulated and more legitimate smart grids developed in response to these.
Corporate social responsibility at the core of new business models
Authors: Lupini Sara
Published: July 2016

Corporate social responsibility (CSR) is a concept subjected to continuous redefinitions and generally addressed with both praise and criticism. CSR shows a great potential, but it also falls short of its promises and aims, being used by companies for boosting their reputation through charitable initiatives and thus lacking substantive impact on the improvement of society. Nowadays, the growing concern about private companies' social and environmental impact is putting pressure on companies to integrate CSR initiatives into their business models, moving towards a more sustainable way of conducting business. A CSR agenda putting social needs and issues at the core might result in the creation of both economic and social values, connecting business and society through long-lasting positive relations. Belize Natural Energy Limited represents a relevant case study for investigating the challenges and opportunities of embracing a culture of sustainability in conducting business. The company starts from setting CSR as a value, including it in the company business model, and committing to integrate with core company operations. The case provides valuable insights regarding the contrast between theory and practice in promoting new business models based on the alignment of societal and commercial values, stimulating reflections and innovative discussions.
Conservation of Tallinn seaplane hangars
Authors: Mändel Maris , Õiger Karl
Published: July 2016

The roof of Tallinn seaplane hangars is among the first, remaining and still-preserved early large reinforced-concrete shells in the world. The hangars were constructed in 1916–1917 by the Danish company Christiani & Nielsen for Tsarist Russian military purposes. The roof consists of three 36·4 × 36·4 m spherical thin reinforced-concrete shells and seven 36·4 × 6·8 m short cylindrical shells attached to them. In 2010–2012, the seaplane hangars were completely renovated for the Estonian Maritime Museum. The high-quality conservation works received the Europa Nostra Grand Prix award in 2013. This study aims to give a comprehensive overview of the conservation process of the Tallinn seaplane hangars from a combined engineering and heritage protection perspective. The paper focuses on the conservation techniques and methods used and explains why and how such approaches were selected. The main findings of previous technical studies are presented to stress the critical technical condition of the hangars before the conservation process. A brief overview of the history of the building is also given, with an emphasis on the uniqueness of the Tallinn seaplane hangars in construction history.
Assessment of U-type wrought iron railway bridges
Authors: Canning Lee , Kashani Mohammad M.
Published: July 2016

A number of assessment codes and guides exist that take into account the particular details of old U-frame types and riveted wrought iron construction; however, a significant number of old bridges still have details that cause difficulty in reliable assessment or require very conservative assumptions, giving low assessed capacity. In this paper, an alternative assessment method using non-linear finite-element analysis of an old U-frame railway bridge is presented. By using the analysis results, some guidelines and recommendations are suggested that are considered to be useful for assessments by the engineering community. However, this approach also has limitations, as it is reliant on assumptions that can be difficult to confirm without extensive field monitoring and experimental testing. The analysis results showed that main girders with non-code-compliant U frames do indeed benefit from a low but significant level of restraint to resist lateral torsional buckling and also that girders that are marginally non-compact based on codified assessment methods may actually have sufficient local stability to provide additional flexural capacity beyond the elastic moment capacity.
Maintenance of structural integrity using cathodic protection
Authors: Beamish Sam , El-Belbol Said , Ngala Vitalis
Published: July 2016

Cathodic protection has been applied to reinforced concrete structures in the UK as a reinforcement corrosion protection technique since the 1980s. It is now well established in the toolbox of repair techniques available for chloride-contaminated reinforced concrete structures. Cathodic protection is an ‘active’ technique and includes an ongoing operation and performance-monitoring commitment. The technique works by introducing an anode through which a small direct current is applied to protect the reinforcement. Monitoring is required to ensure that the current is maintained at the correct level to maintain the reinforcement adequately. This paper provides a brief history of the use of cathodic protection on reinforced concrete in the UK, including the trials and subsequent wholesale use of the technique on the Midland Links motorway viaducts. Also described are the operating and performance-monitoring requirements for cathodic protection systems, including the sensors and monitoring and control equipment used. The paper also discusses the use of monitoring data in the management of cathodic protection systems, and the structures to which they are applied, to predict future performance and life, allowing future maintenance interventions to be planned and providing best value for structure owners.
Investigating rock anchorage failure at major road cut in Wales
Authors: Graham Jim , Solera Sergio , Sanchez Carlos
Published: July 2016

Rock anchorage failures occurring only 6 years after installation to support a major cutting on the A5 trunk road west of Corwen in North Wales were exhaustively investigated, ultimately resulting in their removal and partial replacement. The failures in Glyn Bends rock cutting were detected when head assembly components were found on the ground during a routine inspection. The investigation of the 120-year design life double-corrosion-protected anchorages included the innovative use of endoscopy, selectively supported by subsequent physical dismantling and metallurgical examination. On the basis of the investigation and the subsequent recovery of some of the installed anchorages, it was confirmed that at least 24% of the anchorages originally installed had their factory corrosion protection fatally compromised by partial removal. This was aggravated by the omission of the caps, which allowed the protective grease to escape, and placing many anchorages in recesses which aggravated surface corrosion. Metallurgical investigation emphasised that corrosion protection is critical to very-high-yield steels. No records of the alterations made were ever produced. The trunk road had to be closed at short notice for 8 months on public safety grounds while the main cutting face was reprofiled to a safe unsupported angle on the north side and re-anchored on the south side.
Thermal imaging assessment of drystone retaining walls
Authors: Warren Laura Anne , Briggs Kevin Mark , McCombie Paul Francis
Published: July 2016

Drystone retaining walls form an essential part of the infrastructure in hilly and mountainous regions around the world, by providing platforms for roads, buildings and for agricultural terraces. Research carried out in England and in France has led to a good understanding of their behaviour, but it is difficult to determine the details of the construction of individual walls without dismantling them – so it can be hard to tell if apparent defects and deformations are a threat to stability. Replacing every apparently defective or deformed wall would be a waste of resources, yet dismantling a wall would obviously be completely disruptive to its function. Invasive investigation, such as drilling, could easily cause damage to the wall structure and destabilise the wall. There is therefore a pressing need for non-intrusive methods of investigation that can reveal critical aspects of a wall’s construction. Thermal imaging can reveal important information about aspects of a wall’s construction that are critical to its stability. This paper presents case studies and numerical modelling that have contributed to the development of this technique, and demonstrate its potential.
Clever und Smart
Authors: Maiwald Michael
Published: July 2016

Die gravierenden Veränderungen im Umfeld der Informations- und Kommunikationstechnik beeinflussen auch die Prozessautomation und sind zugleich eine Chance. Denn die Automatisierungskonzepte gemäß Industrie 4.0 sichern den Wettbewerbsvorteil einer Volkswirtschaft. Ein zentrales Element bilden dabei smarte Sensoren, die Dienste innerhalb eines Netzwerks bereitstellen und Information daraus nutzen. Die im November 2015 vorgestellte Technologieroadmap Prozess-Sensoren 4.0 [1] zeigt Anforderungen an smarte Prozess-Sensoren auf. Der Beitrag befasst sich mit den Fragen „Was kann der Prozess-Sensor zu Industrie 4.0 beitragen?“ und „Welchen Nutzen bringt Industrie 4.0 für den Prozess-Sensor?“