25 research outputs found

    Enhancing Bitumen Properties through Worm Mix Asphalt Additives: A Study on Physical and Rheological Characteristics

    Get PDF
    This study aimed to determine how various concentrations of warm mix asphalt (WMA) additives can affect the rheological and physical characteristics of asphalt cement. Bitumen was modified by the chemical additive PAWMA® with an addition ratio of (0.2, 0.4, and 0.6), while the organic additives, Sasobit® and Kaowax®, were added at concentrations of (2, 4, and 6%) by the weight of bitumen. Bitumen hardness, softness, temperature susceptibility, viscosity, and elastic behavior have all been measured using a variety of physical and rheological tests, such as the penetration degree, softening point, penetration index, rotational viscosity, and dynamic shear rheology. This study showed that bitumen physical and rheological properties were affected differently according to the type and percentage of the WMA additive employed. The PAWMA additive, for instance, raised the bitumen penetration while Sasobit® and Kaowax® decreased the bitumen penetration degree. The inverse occurred for the softening point values. All WMA additives lowered bitumen viscosity values. Results from a dynamic shear rheometer (DSR) showed that the rutting index value (G*/Sin) rose, indicating improved rutting resistance

    The Impact of Crumb-Rubber on the Mechanical Characteristics of Modified Asphalt Mixture

    Get PDF
    By following up on the effect of rubber, which has recently been widely used as a direct additive to the asphalt binder or to the concrete mix as a percentage of the weight of the aggregate. The success of the effect of this type of admixture on improving the modified asphalt binder in addition to the modified concrete mix has been investigated. As it was noted the importance of following the asphalt properties due to the increasing use of crumb rubber modifiers in asphalt mixtures, there is a more position to check their rheological and physical properties comprehensively. In general, the performance of the asphalt rubber binder is affected by the rubber crumb content and mixing conditions. This research used 40/50 asphalt grade and Crumb Rubber additives with contents (5, 10, 15, and 20%). The main objectives of this study were to investigate the physical and rheological properties of rubber-modified asphalt binder and mixture. These purposes were achieved by testing HMA samples using the Marshall test approach to determine (Marshall stability and flow and void properties) and measuring the retained Marshall stability and DSR and Viscosity test. Sample testing showed that when recycled rubber was used as modifiers for asphalt mixes, the mixture became more stable, had a higher bulk specific gravity, and had less flow value and air voids. This infers that using recycled rubber can enhance the rutting resistance of bituminous mix

    SPARC 2022 book of abstracts

    Get PDF
    Welcome to the Book of Abstracts for the 2022 SPARC conference. Our conference is called “Moving Forwards” reflecting our re-emergence from the pandemic and our desire to reconnect our PGR community, in celebration of their research. PGRs have continued with their research endeavours despite many challenges, and their ongoing successes are underpinned by the support and guidance of dedicated supervisors and the Doctoral School Team. To recognise supervision excellence we will be awarding our annual Supervisor of the Year prizes, based on the wonderful nominations received from their PGR students.Once again, we have received a tremendous contribution from our postgraduate research community; with over 60 presenters, 12 Three-Minute Thesis finalists, and 20 poster presentations, the conference showcases our extraordinarily vibrant, inclusive, and resilient PGR community at Salford. This year there will be prizes to be won for ‘best in conference’ presentations, in addition to the winners from each parallel session. Audience members too could be in for a treat, with judges handing out spot prizes for the best questions asked, so don’t miss the opportunity to put your hand up. These abstracts provide a taster of the diverse and impactful research in progress and provide delegates with a reference point for networking and initiating critical debate. Take advantage of the hybrid format: in online sessions by posting a comment or by messaging an author to say “Hello”, or by initiating break time discussions about the amazing research you’ve seen if you are with us in person. Who knows what might result from your conversation? With such wide-ranging topics being showcased, we encourage you to take up this great opportunity to engage with researchers working in different subject areas from your own. As recent events have shown, researchers need to collaborate to meet global challenges. Interdisciplinary and international working is increasingly recognised and rewarded by all major research funders. We do hope, therefore, that you will take this opportunity to initiate interdisciplinary conversations with other researchers. A question or comment from a different perspective can shed new light on a project and could lead to exciting collaborations, and that is what SPARC is all about. SPARC is part of a programme of personal and professional development opportunities offered to all postgraduate researchers at Salford. More information about this programme is available on our website: Doctoral School | University of Salford. Registered Salford students can access full details on the Doctoral School hub: Doctoral School Hub - Home (sharepoint.com) You can follow us on Twitter @SalfordPGRs and please use the #SPARC2022 to share your conference experience.We particularly welcome taught students from our undergraduate and master’s programmes as audience members. We hope you enjoy the presentations on offer and that they inspire you to pursue your own research career. If you would like more information about studying for a PhD here at the University of Salford, your lecturers can advise, or you can contact the relevant PGR Support Officer; their details can be found at Doctoral School | University of Salford. We wish you a rich and rewarding conference experience

    A COMPARATIVE STUDY OF PHYSICAL PROPERTIES USING VARIOUS GRADES ASPHALT BINDER WITH DIFFERENT TYPE OF FIBERS

    Get PDF
    For a long time, bitumen has been utilized as the essential material for asphalt pavement construction. The factors of increasing axle loads, increasing traffic movement, critical climate conditions and many forms failures in construction have steered many researchers to seek some methods to enhance the asphalt binder properties. Even though various types of modifiers have been utilized in strengthening asphalt concrete, fibers have attracted the most attention due to their high and desirable characteristics. It is realized that the good distribution of the modifier in asphalt binder can generate a strong network in the interior structure of the blend, causing bitumen mastic to be more coherent. In this study, a laboratory investigation of the rheological and physical properties of various grades of bitumen modified by two types of fibers was conducted. Three grades of asphalt were used in this study (60-70 penetration grade, 80-100 penetration grade and PG-76 grade) with two types of fibers with different percentages- Cellulose oil palm fiber (COPF) (0.15, 0.3, 0.45, 0.6, and 0.75%) by weight of asphalt and carbon fiber (0.75, 1.25, 1.75, 2.25, and 2.75%) by weight of asphalt. The results showed enhancement in physical performance of the modified bitumen in terms of the decrease in penetration values, as well as a rise in the softening point and viscosity values. The fibers’ modified asphalt binders showed improved rheological properties and can raise the grade of asphalt depending on the base asphalt type

    The Impact of Crumb-Rubber on the Mechanical Characteristics of Modified Asphalt Mixture

    No full text
    By following up on the effect of rubber, which has recently been widely used as a direct additive to the asphalt binder or to the concrete mix as a percentage of the weight of the aggregate. The success of the effect of this type of admixture on improving the modified asphalt binder in addition to the modified concrete mix has been investigated. As it was noted the importance of following the asphalt properties due to the increasing use of crumb rubber modifiers in asphalt mixtures, there is a more position to check their rheological and physical properties comprehensively. In general, the performance of the asphalt rubber binder is affected by the rubber crumb content and mixing conditions. This research used 40/50 asphalt grade and Crumb Rubber additives with contents (5, 10, 15, and 20%). The main objectives of this study were to investigate the physical and rheological properties of rubber-modified asphalt binder and mixture. These purposes were achieved by testing HMA samples using the Marshall test approach to determine (Marshall stability and flow and void properties) and measuring the retained Marshall stability and DSR and Viscosity test. Sample testing showed that when recycled rubber was used as modifiers for asphalt mixes, the mixture became more stable, had a higher bulk specific gravity, and had less flow value and air voids. This infers that using recycled rubber can enhance the rutting resistance of bituminous mix

    Enhancing Bitumen Properties through Worm Mix Asphalt Additives: A Study on Physical and Rheological Characteristics

    No full text
    This study aimed to determine how various concentrations of warm mix asphalt (WMA) additives can affect the rheological and physical characteristics of asphalt cement. Bitumen was modified by the chemical additive PAWMA® with an addition ratio of (0.2, 0.4, and 0.6), while the organic additives, Sasobit® and Kaowax®, were added at concentrations of (2, 4, and 6%) by the weight of bitumen. Bitumen hardness, softness, temperature susceptibility, viscosity, and elastic behavior have all been measured using a variety of physical and rheological tests, such as the penetration degree, softening point, penetration index, rotational viscosity, and dynamic shear rheology. This study showed that bitumen physical and rheological properties were affected differently according to the type and percentage of the WMA additive employed. The PAWMA additive, for instance, raised the bitumen penetration while Sasobit® and Kaowax® decreased the bitumen penetration degree. The inverse occurred for the softening point values. All WMA additives lowered bitumen viscosity values. Results from a dynamic shear rheometer (DSR) showed that the rutting index value (G*/Sin) rose, indicating improved rutting resistance
    corecore