THE 'ORIGINAL' STONE MASTIC ASPHALT: THE GERMAN EXPERIENCE
This paper gives an overview of the German experience from the selection of materials, through to design, production and laying of the mixture and will demonstrate why the original German SMA concept has become the most used asphalt mixture for high trafficked roads in Germany. Local Australian practice in the design and application of Stone Matrix Asphalt SMA mixtures will be compared with the German approach. SMA was developed in Germany in the 1960s. It uses an aggregate skeleton and binder mastic to achieve superior loading capacities in heavily trafficked roads when compared with conventional asphalt mixtures. Over the last several decades it has become one of the most used asphalt pavement wearing courses in road construction and, with the expectation of increasing traffic volumes and loads, the use of SMA is predicted to increase. The German SMA design process is based on the careful selection of appropriate aggregate particle grading and quality and on knowledge gained over many years of experience. In 1984 SMA was incorporated into the German technical specifications as a standard construction process. SMA exhibits superior properties in several key areas when compared with conventional asphalt mixtures, these being: (1) resistance to rutting due to slow, heavy and high volume traffic; (2) resistance to deformation at high pavement temperatures; (3) improved skid resistance; (4) noise reduction over conventional alternative pavement surfaces; (4) improved resistance to fatigue effects and cracking at low temperatures; (5) increased durability; and (6) reduced permeability and sensitivity to moisture. The reasons for these positive behaviors of SMA pavement surfaces in heavily trafficked conditions can be attributed to its design principles. The higher proportion of single-sized course aggregate fractions produces a skeleton of interlocking particles and the resultant mechanical interlock is very effective at resisting permanent deformation. The gap-graded principle of SMA also allows for the voids between the coarse aggregate particles to be filled with mastic comprising a relatively high binder content, stabilizing additives and filler. The mastic increases the cohesion, resistance to moisture sensitivity and resistance to fatigue and improves the durability of SMA surfaces. The global uptake of SMA technology in pavement surfacings has seen the implementation of a wide variety of different interpretations of the original German SMA concept.
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Availability:
- Find a library where document is available. Order URL: http://worldcat.org/isbn/087659229X
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Supplemental Notes:
- Full conference proceedings available on CD-ROM.
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Corporate Authors:
ARRB
Melbourne, Victoria Australia -
Authors:
- Kreide, M
- BUDIJA, M
- CARSWELL, J
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Conference:
- Proceedings of the 21st ARRB and 11th REAAA Conference. Transport. Our Highway to a Sustainable Future
- Location: Cairns, Australia
- Date: 2003-5-18 to 2003-5-23
- Publication Date: 2003
Language
- English
Media Info
- Features: Figures; References; Tables;
- Pagination: 17 p.
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Serial:
- Publication of: ARRB Transport Research, Limited
- Publisher: ARRB
- ISSN: 0158-0728
Subject/Index Terms
- TRT Terms: Asphalt pavements; Binder content; Design; Durability; Highway capacity; Mixtures; Moisture content; Particles; Pavements; Permeability; Stone matrix asphalt; Temperature; Traffic; Traffic volume
- Geographic Terms: Germany
- Subject Areas: Design; Highways; Materials; Operations and Traffic Management; Pavements; I31: Bituminous Binders and Materials;
Filing Info
- Accession Number: 00964311
- Record Type: Publication
- ISBN: 087659229X
- Files: TRIS, ATRI
- Created Date: Oct 9 2003 12:00AM