Girao Coelho A.M.,Northumbria University |
Mottram J.T.,University of Warwick |
Matharu N.,Hyder Consulting UK Ltd
Composites Part B: Engineering | Year: 2016
This paper deals with the application of cohesive zone models to study delamination failures in leg-angles of pultruded glass fibre reinforced polymer material using the general-purpose finite element software Abaqus. The objective of the study is to present a finite element modelling methodology that can, for example, help to fill-in knowledge gaps in the available experimental data pertaining to the tying force resistance of angle-cleated jointing in frame construction. It may be used to optimize cleat shape and laminate lay-up (dependent on composite processing method) for the strongest cleat against a minimum cost requirement. A benchmark example taken from literature is used to show that the numerical predictions from the authors' simulations are reliable. The approach is next used to analyse an equal leg-angle component where one leg is fixed and the other orthogonal leg is being deformed by a tensile force applied over the free end surface. Numerical results from Abaqus are used to show that a laminate produced by the pultrusion processing method fails unstably by delamination cracks radiating around the curved region and extending into the leg panels. As a preliminary study to show the potential of the new modelling methodology it is used to show the influence of the radius of curvature at the junction between the legs on the tying force resistance; based on the load at delamination onset a smaller radius reduces the cleat's strength. © 2016 Elsevier Ltd.
Soley R.W.N.,AMEC Environment and Infrastructure |
Power T.,AMEC Environment and Infrastructure |
Mortimore R.N.,ChalkRock Ltd |
Shaw P.,UK Environment Agency |
And 3 more authors.
Geological Society Special Publication | Year: 2012
Six regional recharge and groundwater models have been recently developed of the Chalk and Upper Greensand from Dorset to Kent. Updated Chalk stratigraphy and mapping have improved understanding of geological structure and the development of preferential groundwater flow pathways along hardground horizons. Where shallow dipping folds bring these into the zone of active groundwater flow, extensive 'underdrainage' may result in marked differences between surface and groundwater catchments. Hardgrounds and marls are also associated with spring discharges, as are some faults and the clay formations that underlie or confine the aquifer system. Higher specific yield within the Upper Greensand helps support summer baseflow, as do local groundwater discharges from augmentation schemes, watercress and fish farm operations. The aquifer system has been successfully modelled using the 'variable hydraulic conductivity with depth' version of MODFLOW. Depths of secondary permeability development have been distributed according to ground and groundwater level data. Interfluve-valley contrasts overlie a base hydraulic conductivity set according to the formation saturated at the water table and enhanced by active hardgrounds. Local parameter overrides may also be needed. The Wessex Basin conceptual and numerical model is described before summarizing similarities and contrasts from the other five regional model areas.
McCarthy M.,University College London |
Ravelli R.J.,Hyder Consulting UK Ltd |
Sinclair-Williams M.,Transport for London
European Journal of Public Health | Year: 2010
Background: Transport is a structural determinant of health. We have assessed the potential of transport plans for the 2012 London Olympic Games to achieve the sustainability commitment of 'encouraging healthy living'. Methods: We compared national and London-wide policies against developments described in the Transport Assessment, a public planning document, for the period of the Games and the aftermath legacy. Results: National and London policies recommend modal shift in travel - more walking and cycling for health benefits, and fewer motor vehicles journeys to reduce harm and risks. For the Games, most spectators will use public transport, with low pollution and injury impacts and some are predicted to attend by cycling or walking. Redevelopment of the Olympics site after the Games will provide green areas for cycling and walking and better public transport, but road traffic is predicted to increase and noise and air pollution will persist above recommended levels. Conclusions: Transport planning for the London Olympic Games is contributing to sustainability. The impact on population health should be measured prospectively. © The Author 2010. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
Marrs R.H.,University of Liverpool |
Le Duc M.G.,University of Liverpool |
Smart S.M.,Lancaster University |
Kirby K.J.,Natural England |
And 3 more authors.
Kew Bulletin | Year: 2010
Summary: The invasion of native habitats by exotic, or alien, plant species has received considerable attention recently from policy, research, and practical conservation management perspectives. However, a new hypothesis for species dynamics in Britain suggests that a small number of aggressive native plant species (termed 'thugs') may have an equal, or greater, impact on native species and habitats than exotic species. Here, we examine this hypothesis using multivariate techniques with field-layer cover data collected during a country-wide survey of British woodlands. Multivariate analysis of these data identified a north-south gradient on the first axis, and that 20 of the 25 National Vegetation Classification woodland types were sampled within the study. The most abundant field-layer species included three of the proposed native 'thugs', i. e. Rubus fruticosus, Pteridium aquilinum and Hedera helix in addition to the native woodland indicator species Mercurialis perennis. Variation partitioning was used to compare the relative importance of native field-layer 'thug' species with invading alien shrub and tree species relative to other environmental drivers. The variation in the field-layer data-set explained by the three native 'thug' species was significant, but they explained a relatively small proportion of the variation relative to other environmental variables (climate, soil, management factors etc.). They did, however, explain almost four times as much variation as the three alien species that were significantly correlated with field-layer species composition (Acer pseudoplatanus, Impatiens glandulifera, Rhododendron ponticum). The results of this analysis suggest that the field-layer of British woodlands is impacted as much by native 'thug' species, as it is from 'aliens'. Concern about the impact of these native 'thug' species has been reported previously, but their impact has not previously been compared to the impact of invading aliens. It is hoped that this analysis will do two things, first to act as a sound baseline for assessing any changing balance that should occur in the future, and second, to prompt both ecologists and conservationists to develop woodland management policies based on sound science. © 2011 The Board of Trustees of the Royal Botanic Gardens, Kew.
Cooper L.M.,Hyder Consulting UK Ltd.
Environmental Impact Assessment Review | Year: 2011
This paper examines how cumulative effects assessment (CEA) has been considered in Strategic Environmental Assessments (SEA) of regional and local plans in a number of case studies in the UK. Initially, the paper presents the legislative and regulatory requirements for assessing cumulative effects in plans and programmes in the UK. The two approaches for assessing plans in the UK, Sustainability Appraisal (SA) and SEA are discussed and in most cases, a combined SA and SEA process is undertaken by Regional and Local Planning Authorities. The strengths and weaknesses of this approach are explored, as well as their usefulness in decision making. There are problems relating to baseline, establishing trends and predicting cumulative effects at the strategic level. The issues in assessing cumulative effects within this SA/SEA framework are discussed and recommendations for improvements are made. © 2011 Elsevier Inc.
Maryan P.,Hyder Consulting UK Ltd
Sustainable Business | Year: 2010
Paul Maryan looks at a quicky changing building business aiming to deliver better carbon performance with more emphasis being placed on energy consumption under a new legislation. What is different though is that new legislation like the Carbon Reduction Commitment Energy Efficiency Scheme is now starting to drive behavior change around carbon emissions and to place more importance on energy consumption beyond just the cost. The availability and analysis of energy consumption data is now giving managers in businesses previously uninterested in energy consumption, information about where they are spending their money. The logical conclusion is for tenants to demand more from their buildings and their landlords to help them deliver better energy performance as they come under pressure from the CRC and rising energy prices. A major element of the notional value of a property portfolio is the projected rental income.
Cooper L.M.,Hyder Consulting UK Ltd
Impact Assessment and Project Appraisal | Year: 2010
Network analysis is a technique that has been used in cumulative effects assessment (CEA). In a research project for the Department for Environment, Food and Rural Affairs in the UK, network analysis was used in the context of ecosystem services assessment by defining the services provided by green spaces in Kent Thameside. This paper discusses the results of applying the technique to understand relationships between land uses and ecosystem services and to engage stakeholders. Network analysis can also provide a means to identify key issues and assess cumulative effects in green space planning, sustainability appraisals and strategic environmental assessment (SEA). © IAIA 2010.