Search results for " modified bitumen"
showing 10 items of 10 documents
Are we correctly measuring the rotational viscosity of heterogeneous bituminous binders?
2020
Modified bituminous binders allow asphalt technologists to design asphalt mixtures with superior performance. However, several recent studies highlighted that due to the complexity of these material, their characterisation can be challenging since common procedures used to characterise neat bitumen might not be adequate. For instance, during high temperature rotational viscosity testing of recycled tyre rubber modified binders (RTR-MB), a number of changes may occur to the sample leading to the here-defined sample stability which in turn provides misleading results. In this study the authors want to first provide a deeper understanding of this phenomenon by a numerical analysis using a besp…
Comparison between bitumen modified with crumb tyre rubber and styrene butadiene styrene
2009
The improvements in terms of mechanical properties due to the use of polymers to modify bitumens in road paving applications have already been widely demonstrated. The aim of this paper is to show how the rheology and the performance of a bituminous binder mixed with crumb rubber recycled from used tyres (CR-MB), could be comparable with a styrene butadiene styrene (SBS-MB) created with the same base binder and currently used for road applications. Physical, chemical and performance characterization followed by rheological and storage stability analyses have been undertaken as the basis for the comparison. The results of the investigation indicate that the blended CR-MB shows large improvem…
A simple interpretation of the effect of the polymer type on the properties of PMBs for road paving applications
2018
Abstract The paper presents the results of the rheological characterisation of polymer-modified bitumen for paving applications. In order to find a simple interpretation of the influence of polymer type on the blends produced, in this study high density and low density polyethylene (PE) with different chemical properties were used, as well as ethylene-vinyl acetate. The chemical characteristics of the base bitumen and the polymers used were determined by means of SARA analysis and Fourier Transform Infrared Spectroscopy, FTIR, respectively. The morphology of the produced blends was investigated by means of fluorescent light optic microscopy, while the mechanical properties were investigated…
Improved Testing Setup for Real-Time Monitoring of PMBs During Manufacturing and Rotational Viscosity Measurements
2021
Polymer modified binders (PMBs) are a practical solution to design asphaltmixtures with superior performance. Although these polymers often improve bitumen properties to some extent, their final performance are linked to the accurate control of the properties during manufacturing and storage. However, some of the common procedures used to characterise neat bitumen are not suitable with these binders making their characterisation challenging. This study presents a novel laboratory procedure to produce SBS-MB through a real-time monitoring of the rotational viscosity, as well as an attempt to understand the suitability of current testing geometries to measure viscosity of such a complex bitum…
Optimisation of liquid rubber modified bitumen for road pavements and roofing applications
2020
Abstract Polymer Modified Bitumens (PMBs) are largely used for pavement and roofing membranes applications with Styrene-Butadiene-Styrene Block copolymer (SBS) playing a major role in both markets despite its constantly increasing price due to the rising demand for quality bitumen modifiers. On the other hand, there is an increasing trend of recycling end of life tyres generating Recycled Tyre Rubber (RTR) at affordable price. This investigation aims at engineering a modified bitumen with a combination of Liquid Rubber (LR), a homogeneous blend of 50–70% RTR pre-processed in combination with heavy oils, and a wax denominated Ethylene Bis Stearamide (EBS). In the first phase, the effect of L…
Laboratory investigation into the modification effect of paving bitumen with different plastomeric polymers
2017
The use of polymer/bitumen modified blends in road paving applications has been increasingly advancing from the technological point of view. Plastomeric polymers are known to be amongst the most used in bitumen modification. Therefore, this paper presents the influence and degree of modification of several plastomeric modified bitumen in terms of rheological properties and morphology. Conventional tests such as penetration grade, Ring-and-Ball softening point and storage stability were performed. Rheological properties of the modified blends were characterized in terms of dynamic mechanical analysis via frequency sweep tests using the dynamic shear rheometer (DSR). The morphology of the sam…
EFFECT OF PROCESSING TEMPERATURE VARIATION ON STORAGE STABILITY OF TIRE RUBBER MODIFIED BINDERS
2012
Tire Rubber Modified Binders (TR-MBs), produced through wet process and used worldwide (e.g. asphalt rubber), have been demonstrated to provide various benefits to pavements and, moreover, represent a good opportunity for recycling tire rubber. However, this technology is still struggling to be fully adopted in Europe, mainly because of the poor stability of TR-MBs during high temperature storage, which leads to high initial costs in modifying existing asphalt plants. No-agitation TR-MBs (also known as terminal blends) are proving to be a great option and their development could also be the key to spreading the use of tire rubber in paving applications in Europe. This paper aims to enrich t…
An investigation on using pre-treated tyre rubber as a replacement of synthetic polymers for bitumen modification
2015
Rubberized bitumen obtained through a swelling process, has widely proven to be a successful technology for asphalt pavement applications and a solution to reduce the dismantling of tyre rubber on landfills. However, this technology presents two main operative issues which needs the adoption of costly special equipment. Firstly, significant high value of High Temperature Viscosity (HTV) which imposes mixing and compaction difficulties and leads to increased energy consumption and emissions. Furthermore, during the hot storage period, phase separation between rubber particles and the base bitumen could occur. Developing Recycled Tyre Rubber Modified Bitumen (RTR-MBs) with improved storage st…
Comparison between various bituminous binders modified with crumb tyre rubber
2009
The aim of this paper is to show how the rheology, the performance and the storage stability of different bituminous binders, obtained from two bitumens with different asphaltenes content, change their properties when they are modified with recycled tyre crumb rubber. Physical, chemical and performance characterisation followed by rheological and storage stability analyses have been undertaken as the basis for the comparison. The results of the investigation indicate that bitumen with lower asphaltenes content is more influenced by the modification with the rubber. However, the modification of the bitumen with the higher asphaltenes content gives a binder with better performance and storage…
Preliminary Evaluation of Plasmix Compound from Plastics Packaging Waste for Reuse in Bituminous Pavements
2021
Finding an appropriate technical solution for reusing waste plastics is crucial for creating a circular plastic economy. Although mechanical recycling is the best option for recycling post-consumer plastics, some heterogeneous mixed plastics cannot be recycled to produce secondary material due to their very low properties. In this case, alternative routes should be considered in order to limit their disposal as much as possible. Therefore, in order to solve the environmental problems in the landfills of plastic waste recycling, and to improve the mechanical performance of bitumen for road pavement, the reuse of these post-consumer plastic wastes are preliminarily evaluated for the modificat…