Thermooxidative properties of bituminous binders in relation to their inner chemical compatibility determined by single point precipitation titration (original) (raw)
Related papers
Bitumen Binders Properties – Middle-European Climate Requirements
2017
The article concerns the properties of bitumens and modified binders manufactured in Poland and used inCentral and Eastern Europe for road paving. The aim of the article is to evaluate the properties of bituminous bindersin terms of the climatic conditions of Central and Eastern Europe, taking the Polish climate as an example. In order toobtain a qualitative assessment of binders taking into account their role in the formation of road surface and its operatingconditions in a wide range of temperatures, extensive research of the binders most commonly used in the constructionof asphalt pavement were carried out. Aside from the results of standard tests, this article also presents theresults of studies determining the functional properties of binders according to the SUPERPAVE method.Based on the results, it was found that the bituminous binders meet the requirements specified in European standardsand technical guidelines. The temperature range of viscoelasticity of all the tested bitu...
XXVI PIARC World Road Congress, Abu Dhabi, 2019
In the wake of a growing bitumen binder variability resulting from economic and geopolitical constraints leading to changes in crude oils and refining processes, the asphalt industry is facing challenges of quality, consistency and early pavement failures in the form of cracking and raveling in particular. New, innovative and relevant analytical tools and approaches are being developed particularly at the Western Research Institute (WRI) to address the challenges and advance from trials and errors to modelling and predictions. Studies launched by WRI have demonstrated the proof of concept, and the validation of chemometric correlations; linking chemical composition of bitumen binders to their physical properties and their performance in mixes. Relevant strong correlations were obtained for compositional fractions, chemical functionalities, and thermal parameters with binder rheological properties, specification parameters, as well as asphalt mix properties, through a study with a road contractor. Hence, the binder impacts mixture stiffness and fatigue resistance, but less prominently in mixture resistance to moisture-induced damaged, rutting resistance and compaction properties, where aggregates become more prominent. Other important results confirmed some performance indicators from binder to mixes, such as the stiffness modulus, fatigue parameters, thermal cracking parameters (relaxation and cracking temperature), and rutting resistance. New possible indicators were detected like the binder glass transition and crossover temperatures as well as their difference, named temperature of intermediate region (TIR) with respect to cracking resistance and healing propensity. The effect of long term aging, particularly with respect to cracking, was also evaluated. Many of these results have been obtained through two major projects: the Asphalt Industry Research Consortium launched by WRI which is ongoing on a very wide binder range aiming to chemically fingerprint binders to predict their mechanical properties as well as their aging susceptibility and their compatibility with various modifiers or recycled materials. The second project is the ongoing National Cooperative Highway Research Program 09-60 project. This involves studying the impact of binder resistance to internal restraint damage mechanism on mixture cracking, and the influence of other thermal cracking factors such as, long-term aging and reversible time-dependent physical hardening. The ultimate goal of this project is to develop and propose new and more relevant specification parameters to avoid age-induced surface damage in the form of transverse cracking, block cracking, and raveling.
Influence of the thermal history on the rheological properties of modified 1 bitumens 2
2018
14 Due to the wide variation in geographic and climatic conditions, the growing demands of 15 resistant bituminous materials to various environmental conditions have resulted in a search for 16 bitumen modifiers capable to reduce the temperature susceptibility of the binder in the service 17 temperature range. Therefore, in the present contribution, the effects of addition of low 18 molecular weight organic compounds on temperature susceptibility of asphalt binders were 19 investigated by a combination of dynamics oscillatory rheology and Atomic Force Microscopy 20 (AFM). The results analyzed on the basis of weak gel model were found useful to discriminate 21 the selected additives regarding their relative capacity to favor coarse or fine colloidal 22 aggregates, which in turn were responsible for the observed bulk rheological behaviour. 23
Influence of thermal history on rheological properties of various bitumen
Rheologica Acta, 2006
The mechanical properties of bituminous binders play an important role in the performance of the corresponding asphalt mix, and a lot of failure mechanisms in asphalt roads are believed to relate to a rheologcal aspect of the corresponding bituminous binder. In 1994, the strategic highway research program was the first to propose performance related specifications, which were based on rheological properties of the binders, taking into account the climatic and loading conditions of the pavement. Also, in the future European specifications, a lot of the tests will be based on rheological properties.
Jurnal Teknologi, 2017
Polymer modified bitumen (PMB) has been used for many years to improve the performance of asphalt concretes against premature pavement defects. In this research, modified samples were prepared with 2%, 3%, 4%, 5% and 6% Linear Low Density Polyethylene (LLDPE) polymer by weight of bitumen binder. The influence of LLDPE polymer was evaluated through binder properties test which includes penetration, softening point, storage stability, temperature susceptibility, rutting, fatigue and thermal oxidative aging resistance from a dynamic shear rheometer (DSR) measurements at a temperature of 20 OC to 60 OC. Results show that LLDPE polymer has a significant effect on binder properties. Penetration decreases and softening point increases with increasing LLDPE content on the modified binder after aging, which implies LLDPE improves the thermo oxidative aging resistance of the binder. Furthermore, the storage stability test shows that at higher LLDPE concentrations phase separation may occur. D...
Exploring the Effect of Organic Additives on Physical Properties of Bitumen
Elektronički časopis građevinskog fakulteta Osijek, 2021
Warm additives had wide popularity in recent years due to saving in energy and lowering emissions dealt with asphalt mixture production. Warm Mix Asphalt (WMA) is produced by using foaming technology or reducing -viscosity additives of binder to enhance the rheological properties. In this study, organic-based additives (Asphaltan A and Asphaltan B) are used to investigate their effect to minimize the viscosity and lower the temperature of asphalt mixture production. Bitumen is mixed with three doses of each additive: 1, 2, and 3% of its weight. The binder viscosity was measured by rotational viscometer with and without the additives at three different temperatures. The study showed that the organic additives have a positive impact on the behavior of the binder in terms of viscosity reduction and made enhancements in terms of bitumen properties. This result could be useful in the reduction of production temperature and quantity of odour emissions.
Eurasian Chemico-Technological Journal, 2021
This paper deals with the fundamental differences between industrial and pavinggrade bituminous binders. The paper is presented in two main sections: 1) a review of the materials' colloidal structure and the required properties for the industrial and paving applications; 2) a wide range of experimental tests with which the bituminous binders were studied and compared. In this research, a 160/220 industrial bitumen was studied and compared to a paving-grade bitumen with the same penetration and with a lower penetration, 70/100 one. The research consisted of physical, chemical, thermal, microstructural, and rheological analysis to provide a comprehensive understanding of these bituminous binders of diverse applications. Overall, the comparison of the tests' results indicated that while the asphaltene content and its characteristics have a great influence on the bitumen's properties, it is not the only fundamental factor. During the study of the chemical structures via Atomic Force Microscopy (AFM), it was found that the Peri phase (attributed to the resins) also plays an important role, defining the bitumen's physical visco-elastic properties. In fact, from a microstructural point of view using AFM a significant difference was notified between the industrial bitumen and the paving-grade ones. These differences allow the paving-grade bitumens to be more elastic and ductile compared to the industrial bitumen.
Effect of short-term ageing temperature on bitumen properties
Road Materials and Pavement Design, 2017
Properties of asphalt mixtures after ageing are fundamental parameters in determining longterm performance (e.g. durability) of these materials. With increasing popularity of reduced temperature mixtures, such as warm-mix asphalt, WMA, the question remains how a reduction in short-term ageing affects the properties after long-term ageing of bituminous materials. This paper aims to improve our understanding of the effect of asphalt manufacturing temperature on ageing and the resulting mechanical properties of bituminous binder by studying the effect of short-and long-term ageing of different bitumen samples as a function of short-term ageing temperatures. For this purpose, round robin experiments were conducted within the RILEM technical committee (TC) 252 chemo-mechanical characterisation of bituminous materials by 10 laboratories from 5 countries using four binders of the same grade (70/100 pen) from different crude sources. The short-term ageing was carried out using the standard procedure for rolling thin film oven test (RTFOT), but varying the temperatures. Long-term ageing was carried out using the standard procedure for pressure aging vessel (PAV) in addition to RTFOT. For the mechanical characterisation, rheological data were determined by using the dynamic shear rheometer (DSR) and conventional tests, with needle penetration and softening point using the ring and ball method. The results show that although different short-term ageing temperatures showed a significant difference in the mechanical properties of the binders, these differences vanished after long-term ageing with PAV.
An alternative method for short- and long-term ageing for bitumen binders
Road Materials and Pavement Design, 2013
Short-term ageing of bituminous binders is a well-accepted concept that represents ageing of binders during plant mixing, production, transportation and construction. Simulation of this ageing is carried out in controlled laboratory conditions and these aged binders are used to predict binder rutting performance. Similarly, the simulation of long-term ageing of binders accounts to ageing of the binder during service life of the pavements and these binders are used to characterise the binder response to fatigue performance in the SUPERPAVE test protocol. Two well-established laboratory test methods are generally practised for evaluating the short-term ageing of bitumen binders: (i) the thin film oven (TFO) test method where a pan filled with bitumen is placed on a rotating pan on the horizontal plane and (ii) the rolling TFO (RTFO) method that uses cylindrical glass bottles filled with bitumen which are rolled in the vertical plane. In the case of long-term ageing, simulation is performed in a pressurised ageing vessel (PAV) under constant conditioning of pressure and temperature. The RTFO and PAV are the part of the test protocol of SUPERPAVE specifications. These equipments are costly and may not be available to different agencies and thereby it has become difficult to adopt any studies involving short- and long-term ageing of binders. Any alternative procedure developed that provides similar ageing effects comparable to the SUPERPAVE method would help highway agencies to adopt and study the effect of ageing on binders. Keeping this as the main concern, an attempt is made to develop a cheap and generalised method for short-term and long-term ageing effects using a normal laboratory oven. Six binder types consisting of two each from viscosity grades, penetration-grade polymer-modified binders (PMB) and crumb rubber-modified binders, were considered in this study. Binders were aged in RTFO and PAV ageing and tested for rheological properties using the dynamic shear rheometer. Similarly, these binders were also aged in a normal oven kept at a constant temperature for varying periods of ageing. Test results were compared on the basis of rutting and fatigue criteria to arrive at the time of ageing required in a normal oven that would be similar to RTFO and PAV ageing, respectively. The study revealed that it is possible to correlate ageing methods of SUPERPAVE with a normal oven method and arrive at an alternative method of ageing. In order to compare the actual short-term ageing of one of the modified binders, bituminous mixes were collected from the field during mix production, transportation and compaction, and binders from these were extracted. Rheological parameters of the extracted bitumen from field samples collected during different stages of construction, RTFO and normal oven-aged samples were evaluated and compared. It was found that the actual ageing is different from RTFO and a normal oven ageing and thereby there is a need to carryout a detailed study on ageing characteristics of Indian binders.
Impact of temperature on short- and long-term aging of asphalt binders
RILEM Technical Letters, 2016
Properties of asphalt concrete after aging are important parameters in determining the long-term performance of these materials. With the popularity of reduced temperature mixtures the question remains how this reduced temperature in short-term aging affects the long-term properties. This paper focuses on developing a robust and fundamental understanding of the effect of temperature on aging by connecting the chemistry of bitumen to its mechanics. To this end, round robin experiments are being currently conducted within 8 laboratories using four binders of the same grade 70/100 pen from different crude sources. In developing chemo-mechanical characterization techniques at the nano- and micro-scale, the material’s variability from crude-source to crude-source and its sensitivity to temperature needs to be taken into consideration. Furthermore, the development of uniform specimen preparation procedures for these bituminous materials at the nano- and micro-structural level is the focus...