scholarly journals Sustainable low-temperature asphalt mixtures with marginal porous volcanic aggregates and crumb rubber modified bitumen

2019 ◽  
Vol 207 ◽  
pp. 44-56 ◽  
Author(s):  
Miguel A. Franesqui ◽  
Jorge Yepes ◽  
Cándida García-González ◽  
Juan Gallego
Keyword(s):  
Low Temperature ◽  
Crumb Rubber ◽  
Asphalt Mixtures ◽  
Modified Bitumen

scholarly journals Evolution of Rheological Behaviors of Styrene-Butadiene-Styrene/Crumb Rubber Composite Modified Bitumen after Different Long-Term Aging Processes

Materials ◽  
2019 ◽  
Vol 12 (15) ◽  
pp. 2345 ◽  
Author(s):  
Yangsheng Ye ◽  
Gang Xu ◽  
Liangwei Lou ◽  
Xianhua Chen ◽  
Degou Cai ◽  
...  
Keyword(s):  
Low Temperature ◽  
High Speed ◽  
Crumb Rubber ◽  
Modified Bitumen ◽  
High Speed Railway ◽  
Modified Asphalt ◽  
Styrene Butadiene Styrene ◽  
Styrene Butadiene ◽  
Butadiene Styrene

In this study, a new type of composite modified bitumen was developed by blending styrene-butadiene-styrene (SBS) and crumb rubber (CR) with a chemical method to satisfy the durability requirements of waterproofing material in the waterproofing layer of high-speed railway subgrade. A pressure-aging-vessel test for 20, 40 and 80 h were conducted to obtain bitumen samples in different long-term aging conditions. Multiple stress creep recovery (MSCR) tests, linear amplitude scanning tests and bending beam rheometer tests were conducted on three kinds of asphalt binders (SBS modified asphalt, CR modified asphalt and SBS/CR composite modified asphalt) after different long-term aging processes, including high temperature permanent deformation performance, resistance to low temperature thermal and fatigue crack. Meanwhile, aging sensitivities were compared by different rheological indices. Results showed that SBS/CR composite modified asphalt possessed the best properties before and after aging. The elastic property of CR in SBS/CR composite modified asphalt improved the ability to resist low temperature thermal and fatigue cracks at a range of low and middle temperatures. Simultaneously, the copolymer network of SBS and CR significantly improved the elastic response of the asphalt SBS/CR modified asphalt at a range of high temperatures. Furthermore, all test results indicated that the SBS/CR modified asphalt possesses the outstanding ability to anti-aging. SBS/CR is an ideal kind of asphalt to satisfy the demand of 60 years of service life in the subgrade of high speed railway.

Evaluation on Mix Design and Rutting Resistance of Dry Mixed Rubberised Asphalt Mixtures

2013 ◽  
Vol 65 (3) ◽  
Author(s):  
Norhidayah Abdul Hassan ◽  
Mohd Rosli Hainin ◽  
Haryati Yaacob ◽  
Che Ros Ismail ◽  
Nur Zurairahetty Mohd Yunus
Keyword(s):  
Asphalt Mixture ◽  
Crumb Rubber ◽  
Asphalt Mixtures ◽  
Mix Design ◽  
Laboratory Evaluation ◽  
Modified Bitumen ◽  
Dry Process ◽  
Stone Mastic Asphalt ◽  
Wheel Tracking Test ◽  
Wheel Tracking

This study presents a laboratory evaluation on the properties of crumb rubber modified asphalt mixture using a dry process method in which the fine crumb rubber is added to substitute the aggregates portion and acts as elastic aggregates within the mix. The effect of crumb rubber in the mixture was investigated in terms of the volumetric properties using Marshall Mix Design and rutting performance using Wheel Tracking Test. The crumb rubber was added between 1 to 3% in steps of 1% by weight of aggregates to modify a dense graded mix, Asphaltic Concrete (AC14) and a gap graded mix, Stone Mastic Asphalt (SMA14) according to the Malaysian mix design. Based on the result, it was observed that the performance of the asphalt mixtures was significantly affected with the addition of crumb rubber. Rubberised asphalt mixtures for AC14 were found to have a greater resistance on rutting deformation compared to the conventional mixture. However, the use of fine rubber in SMA14 mixture with 80/100 bitumen cannot provide enough binder modification to perform as good as conventional SMA14 mixture with polymer modified bitumen. Furthermore, based on detailed review, a set of procedures for producing dry mixed rubberised asphalt mixture was identified and recommended for future studies.

Experimental Fracture Toughness Study for some Modified Asphalt Mixtures

2013 ◽  
Vol 723 ◽  
pp. 337-344 ◽  
Author(s):  
Hamid Behbahani ◽  
Mohammad Reza Mohammad Aliha ◽  
Hassan Fazaeli ◽  
Somayeh Aghajani
Keyword(s):  
Fracture Toughness ◽  
Low Temperature ◽  
Asphalt Mixture ◽  
Crumb Rubber ◽  
Asphalt Mixtures ◽  
Subzero Temperature ◽  
Mode I ◽  
Maximum Increase ◽  
Mode I Fracture ◽  
Mode I Fracture Toughness

The use of modifiers or additives in the asphalt mixtures is a suitable and common method for improving their mechanical properties especially under high temperature service conditions. However, for cold climates which the pavement of roads usually experience subzero temperatures, the overall failure mechanism of asphalt layers may be occurred mainly due to elastic brittle fracture and growth of initiated cracks inside the pavements. Fracture toughness is the most important parameter for characterizing the crack growth and failure of cracked materials and structures such as the asphalt pavements. Hence, the main aim of this research is to study the effect of different additives including Poly phosphoric acid (PPA), Styrene butadiene styrene (SBS), Anti striping agent (ANTI), Crumb rubber (CR) and FT-paraffin wax (Sasobit) on the low temperature mode I fracture resistance of asphalt mixtures. A series of asphalt samples with different percentages of the mentioned additives were manufactured in the shape of semi circular specimens containing vertical edge cracks. The test samples were then loaded monotonically using a symmetric three-point bend fixture at a constant subzero temperature of-15°C. The value of mode I fracture toughness (KIc) were determined by recording the critical fracture loads of tested specimens. It is shown that all the investigated additives increase the low temperature fracture toughness of the asphalt mixture and the maximum increase in the value of KIc occurs when the sasobit and CR additives are used.

scholarly journals Recyclability of Asphalt Mixtures with Crumb Rubber Incorporated by Dry Process: A Laboratory Investigation

Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2870
Author(s):  
Israel Rodríguez-Fernández ◽  
Maria Chiara Cavalli ◽  
Lily Poulikakos ◽  
Moises Bueno
Keyword(s):  
Urban Areas ◽  
Mechanical Performance ◽  
Asphalt Binder ◽  
Aging Effect ◽  
Crumb Rubber ◽  
Low Noise ◽  
Asphalt Mixtures ◽  
Polymer Modification ◽  
Modified Bitumen ◽  
Dry Process

Semi-Dense Asphalt (SDA) mixtures are nowadays recommended for the surface layer of low noise roads in urban areas due to their optimal functional characteristics. Moreover, the use of polymer-modified bitumen (PmB) in its design results in high mechanical performance. However, this type of highly modified bitumen implies significant economic and environmental disadvantages. The polymer modification increases the production cost, involves higher mixing temperatures, and makes the recycling process of the asphalt mixtures challenging. As a potential alternative to PmB in SDA mixtures, this experimental work analyses the dry process for the incorporation of crumb rubber (CR) from waste tires. Particularly, the main objective was to study the aging effect and the recyclability of asphalt mixtures prepared in the laboratory with two different types of CR. The volumetric properties and mechanical performance of the mixtures artificially aged and rejuvenated were evaluated. The results obtained show that mixtures with CR have adequate performance, being less susceptible to aging than a conventional polymer-modified mixture. Furthermore, the rheological response of asphalt binder samples recovered from the mixtures at different aging states was analyzed. It was observed that the effect of the rejuvenator depended on the CR type, but this fact did not negatively influence the performance of the recycled mixtures.

scholarly journals High and Low Temperature Properties of FT-Paraffin-Modified Bitumen

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Hassan Fazaeli ◽  
Hamid Behbahani ◽  
Amir Ali Amini ◽  
Jafar Rahmani ◽  
Golazin Yadollahi
Keyword(s):  
Low Temperature ◽  
High Temperatures ◽  
Low Temperatures ◽  
Permanent Deformation ◽  
Weight Percent ◽  
Asphalt Mixtures ◽  
Considerable Influence ◽  
Modified Bitumen ◽  
Fischer Tropsch ◽  
Performance Grade

This paper presents the results of an experimental research on the effects of “Fischer Tropsch-Paraffin” (Sasobit) content on physical and rheological properties of Sasobit modified bitumen at various operational temperatures. For this purpose, bitumen with a Performance Grade (PG) of 58–22 is selected as the base and later it is modified with 1, 2, 2.5, 3, and 4 weight percent of FT-Paraffin (Sasobit). The performance of modified bitumen at high, intermediate, and low temperatures is evaluated based on Strategic Highway Research Program (SHRP) Superpave tests. Results of the study show that FT-paraffin improves the performance of bitumen at high temperatures in addition to increasing the resistance of mixture against permanent deformation. Despite the advantages of FT-paraffin on bitumen performance at high temperatures, it does not show a considerable influence on the intermediate and low temperature performance of bitumen. The effect of FT-paraffin content on the viscosity of modified bitumen is also investigated using Brookfield Viscometer Apparatus. Results show that increasing the additive content lowers the viscosity of modified bitumen. This in return can reduce the mixing and compaction temperature of asphalt mixtures.

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