Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
New experimental methods for characterizing formation and decay of foam bitumen
KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials. EMPA, Swiss Federal Laboratories for Material Science and Technology, Switzerland.
2015 (English)In: Materials and Structures, ISSN 1359-5997, E-ISSN 1871-6873Article in journal (Refereed) Published
Abstract [en]

Formation and decay of foam bitumen is a highly dynamic temperature dependent process which makes characterization difficult. In this research, new experimental tools were applied for characterizing the bitumen foam during the foaming process. Ultrasonic sensors were used for accurately monitoring the expansion and decay of foam bitumen as a function of time. Assessment of foam bitumen viscosity was performed using high frequency torsional rheometer and in situ observation by X-ray radiography. A high-speed camera was applied for examining the foam bitumen stream right at the nozzle revealing that foam bitumen at a very early stage contains fragmented pieces of irregular size rather resembling a liquid than foam. Moreover, infrared thermal images were taken for obtaining information on the in situ surface temperature of foam bitumen during the hot foaming process. The result showed that the average surface temperature of foam bitumen depends on the water content of the bitumen and bubble size distribution, 108 and 126 °C for 4 and 1 wt% (by weight) water content respectively. The residual water content in the decaying foam bitumen was determined by thermogravimetric analysis. The result demonstrated that residual water content depends on the initial water content, and was found to be between 38 and 48 wt% of the initial water content of 4–6 wt%. Finally, X-ray computed tomography was applied for examining the decay of foam bitumen revealing that the bubbles of foam bitumen remain trapped close to the surface of the foam bitumen.

Place, publisher, year, edition, pages
2015.
Keyword [en]
Foam bitumen characterization, Process monitoring, Thermal properties, X-ray analysis, Atmospheric temperature, Bubble columns, Computerized tomography, Decay (organic), High speed cameras, Surface properties, Thermodynamic properties, Thermogravimetric analysis, X ray analysis, X ray radiography, Bubble size distributions, Foam bitumens, Infrared thermal image, Initial water contents, New experimental method, Residual water content, Temperature dependent, X-ray computed tomography, Bituminous materials
National Category
Materials Engineering
Identifiers
URN: urn:nbn:se:kth:diva-177222DOI: 10.1617/s11527-015-0659-6OAI: oai:DiVA.org:kth-177222DiVA: diva2:873988
Note

QC 20151125

Available from: 2015-11-25 Created: 2015-11-17 Last updated: 2017-12-01Bibliographically approved
In thesis
1. Morphology Characterization of Foam Bitumen and Modeling for Low Temperature Asphalt Concrete
Open this publication in new window or tab >>Morphology Characterization of Foam Bitumen and Modeling for Low Temperature Asphalt Concrete
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Development of new asphalt technologies to reduce both energy consumption and CO2 production has attracted great interest in recent years. The use of foam bitumen, as one of them, is attractive due to the low investment and production cost. Formation and decay of foam bitumen is a highly dynamic temperature dependent process which makes characterization difficult. In this thesis, new experimental tools were developed and applied for characterizing the foam bitumen during the hot foaming process. 

One of the main goals of this study was to improve understanding and characterization of the foam bitumen formation and decay. X-ray radiography was used to study the formation and decay of foam bitumen in 2D representation. The results demonstrate that the morphology of bubble formation depends on the types of bitumen used. Moreover, theoretical investigation based on the 3D X-ray computed tomography scan dataset of bubble merging showed that the disjoining pressure increased as the gap between the bubbles in the surface layer (foam film) decreased with time and finally was ruptured. 

 Examining the foam bitumen stream right at the nozzle revealed that foam bitumen at a very early stage contains fragmented pieces of irregular size rather resembling a liquid than foam. The result from thermogravimetric analysis demonstrated that residual water content depends on the initial water content, and was found to be between 38 wt% and 48 wt% of the initial water content of 4 wt% to 6 wt%.

Moreover the influence of viscosity and surface tension on bubble shape and rise velocity of the bubbles using level-set method was implemented in finite element method. The modeling results were compared with bubble shape correlation map from literature. The results indicated that the bubble shapes are more dependent on the surface tension parameters than to the viscosity of the bitumen, whereas the bitumen viscosity is dominant for bubble rising velocity.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2016. xiv, 134 p.
Series
TRITA-BYMA, ISSN 0349-5752 ; 2016:1
Keyword
foam characteristics, evolution of foam bitumen bubbles, image analysis, modeling rising of bubble, foam asphalt mixture
National Category
Infrastructure Engineering
Research subject
Transport Science
Identifiers
urn:nbn:se:kth:diva-183105 (URN)978-91-7595-865-1 (ISBN)
Public defence
2016-04-01, Kollegiesalen, Brinellvägen 8, KTH, Stockholm, 13:00 (English)
Opponent
Supervisors
Note

QC 20160303

Available from: 2016-03-03 Created: 2016-02-29 Last updated: 2016-03-09Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Hailesilassie, Biruk WobeshetPartl, Manfred N.
By organisation
Highway and Railway EngineeringBuilding Materials
In the same journal
Materials and Structures
Materials Engineering

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 208 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf