Donna James - Academia.edu (original) (raw)
Papers by Donna James
Specific contributions to climate change - carbon footprints - now feature in the claims of many ... more Specific contributions to climate change - carbon footprints - now feature in the claims of many products, giving a basis for potential customers to procure on environmental as well as economic terms. This paper describes a consistent approach to carbon footprinting devised for asphalt products, developed through a collaborative effort by the UK highways sector, with representation from clients, industry and the research community. The asphalt Pavement Embodied Carbon Tool (asPECT), consisting of protocol documentation and software, takes a life cycle approach that follows the Publically Available Specification PAS 2050:2008 and facilitates assessment of greenhouse gas contributions from raw material acquisition, through to product production, installation, maintenance and end-of-life. The method provides the resolution to allow factors such as individual constituent material contributions, recycled content, energy consumption in heating and mixing and transport modes to be reflecte...
Proceedings of the Institution of Civil Engineers - Construction Materials, 2013
A selection of the available literature on warm mix asphalt and half-warm mix asphalt were review... more A selection of the available literature on warm mix asphalt and half-warm mix asphalt were reviewed in order to ascertain whether some or all of the currently available technologies have a potential use on the UK Highways Agency's network. The review looked at the various categories of the technology, the differences required in site practices, the performance of the resulting asphalt and the environmental and economic advantages of their use. However, because there is considerably more literature than that included in this study, the findings can only be tentative.
Asphalt Pavements, 2014
The OECD is a unique forum where the governments of 30 democracies work together to address the e... more The OECD is a unique forum where the governments of 30 democracies work together to address the economic, social and environmental challenges of globalisation. The OECD is also at the forefront of efforts to understand and to help governments respond to new developments and concerns, such as corporate governance, the information economy and the challenges of an ageing population. The Organisation provides a setting where governments can compare policy experiences, seek answers to common problems, identify good practice and work to coordinate domestic and international policies.
Proceedings of 6th Eurasphalt & Eurobitume Congress, 2016
Lower temperature asphalts (LTAs) have been identified as a way of reducing both the energy requi... more Lower temperature asphalts (LTAs) have been identified as a way of reducing both the energy required to produce and lay asphalt materials and the nuisance of fumes for workers. The use of LTAs has not yet reached its full potential in the United Kingdom. To encourage uptake in appropriate applications and inform the national specifications, a project was undertaken to demonstrate use of a LTA on the strategic road network. The project was realised as a result of successful collaboration between the national road authority, industry and a research organisation. A site with sections of LTA surface and binder course mixtures produced using an 'injection foaming' technology was laid and monitored for initial properties. Sections of conventional hot mix materials were also laid and monitored to enable direct comparison. Visual inspection, temperature measurement and thermographic imaging were undertaken at regular intervals throughout construction. Physical properties of the materials used were established through laboratory testing of samples taken at site and the carbon footprint of construction was evaluated. Overall, the demonstration proved that effective application of an LTA technology could be achieved but also yielded some important practical messages for the future application of LTAs.
Proceedings of 6th Eurasphalt & Eurobitume Congress, 2016
Traditional asphalt pavement design is based on a mechanistic-empirical approach which identifies... more Traditional asphalt pavement design is based on a mechanistic-empirical approach which identifies the strain at critical locations in the pavement structure to safeguard the road against fatigue and structural deformation. However, research has shown that when roads are well built above a certain threshold, structural damage is non-existent with rutting confined to the surfacing, an ideal and economic design solution. The existence of these 'long-life' pavements challenges the current design and maintenance methodologies and suggests a need for a radical approach to pavement design. Although findings from global research have verified that a threshold effect for pavements does exist, there is limited real life data to support this theory. This paper, sponsored by Highways England, aims to demonstrate the threshold effect as well as develop a radical approach to flexible pavement design and maintenance, using the threshold concept. Three instrumented road sections of varying thicknesses were designed, built, and trafficked under varying wheel loads and speed. The results demonstrated classical pavement deterioration through both rutting and fatigue cracking. However, one of the sections showed no deterioration and the associated strains illustrate the threshold effect. In addition, a methodology is presented which involves the development of a robust model that predicts tensile asphalt strains directly from falling weight deflectometer (FWD) measurements which could be used as a tool to identify long life pavements on the English Strategic Road Network (SRN).
Specific contributions to climate change - carbon footprints - now feature in the claims of many ... more Specific contributions to climate change - carbon footprints - now feature in the claims of many products, giving a basis for potential customers to procure on environmental as well as economic terms. This paper describes a consistent approach to carbon footprinting devised for asphalt products, developed through a collaborative effort by the UK highways sector, with representation from clients, industry and the research community. The asphalt Pavement Embodied Carbon Tool (asPECT), consisting of protocol documentation and software, takes a life cycle approach that follows the Publically Available Specification PAS 2050:2008 and facilitates assessment of greenhouse gas contributions from raw material acquisition, through to product production, installation, maintenance and end-of-life. The method provides the resolution to allow factors such as individual constituent material contributions, recycled content, energy consumption in heating and mixing and transport modes to be reflecte...
Proceedings of the Institution of Civil Engineers - Construction Materials, 2013
A selection of the available literature on warm mix asphalt and half-warm mix asphalt were review... more A selection of the available literature on warm mix asphalt and half-warm mix asphalt were reviewed in order to ascertain whether some or all of the currently available technologies have a potential use on the UK Highways Agency's network. The review looked at the various categories of the technology, the differences required in site practices, the performance of the resulting asphalt and the environmental and economic advantages of their use. However, because there is considerably more literature than that included in this study, the findings can only be tentative.
Asphalt Pavements, 2014
The OECD is a unique forum where the governments of 30 democracies work together to address the e... more The OECD is a unique forum where the governments of 30 democracies work together to address the economic, social and environmental challenges of globalisation. The OECD is also at the forefront of efforts to understand and to help governments respond to new developments and concerns, such as corporate governance, the information economy and the challenges of an ageing population. The Organisation provides a setting where governments can compare policy experiences, seek answers to common problems, identify good practice and work to coordinate domestic and international policies.
Proceedings of 6th Eurasphalt & Eurobitume Congress, 2016
Lower temperature asphalts (LTAs) have been identified as a way of reducing both the energy requi... more Lower temperature asphalts (LTAs) have been identified as a way of reducing both the energy required to produce and lay asphalt materials and the nuisance of fumes for workers. The use of LTAs has not yet reached its full potential in the United Kingdom. To encourage uptake in appropriate applications and inform the national specifications, a project was undertaken to demonstrate use of a LTA on the strategic road network. The project was realised as a result of successful collaboration between the national road authority, industry and a research organisation. A site with sections of LTA surface and binder course mixtures produced using an 'injection foaming' technology was laid and monitored for initial properties. Sections of conventional hot mix materials were also laid and monitored to enable direct comparison. Visual inspection, temperature measurement and thermographic imaging were undertaken at regular intervals throughout construction. Physical properties of the materials used were established through laboratory testing of samples taken at site and the carbon footprint of construction was evaluated. Overall, the demonstration proved that effective application of an LTA technology could be achieved but also yielded some important practical messages for the future application of LTAs.
Proceedings of 6th Eurasphalt & Eurobitume Congress, 2016
Traditional asphalt pavement design is based on a mechanistic-empirical approach which identifies... more Traditional asphalt pavement design is based on a mechanistic-empirical approach which identifies the strain at critical locations in the pavement structure to safeguard the road against fatigue and structural deformation. However, research has shown that when roads are well built above a certain threshold, structural damage is non-existent with rutting confined to the surfacing, an ideal and economic design solution. The existence of these 'long-life' pavements challenges the current design and maintenance methodologies and suggests a need for a radical approach to pavement design. Although findings from global research have verified that a threshold effect for pavements does exist, there is limited real life data to support this theory. This paper, sponsored by Highways England, aims to demonstrate the threshold effect as well as develop a radical approach to flexible pavement design and maintenance, using the threshold concept. Three instrumented road sections of varying thicknesses were designed, built, and trafficked under varying wheel loads and speed. The results demonstrated classical pavement deterioration through both rutting and fatigue cracking. However, one of the sections showed no deterioration and the associated strains illustrate the threshold effect. In addition, a methodology is presented which involves the development of a robust model that predicts tensile asphalt strains directly from falling weight deflectometer (FWD) measurements which could be used as a tool to identify long life pavements on the English Strategic Road Network (SRN).