Mastic asphalt

MA is perhaps the oldest mixture, developed almost at the same time in England and in 

The primary features of this mixture, in comparison to all the abovementioned asphalts, are its high filler content, its higher binder content, its almost zero permeability, its use of harder bitumen and its high cost primarily due to the high binder content incorporated. 

MA is designated as a voidless bituminous mixture in which the filler volume and binder volume exceed the remaining volume of voids in the mix. 

MA may be used in roads, airfields and other trafficked areas for surface courses or binder courses. MA is primarily used for protection layers and inter-layers for bridges, tunnels and roughs. It should not be confused with MA for waterproofing purposes in the construction and civil engineering fields specified in CEN/TC 314-MA for waterproofing. 

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Two possible forms of membrane are hot applied mastic asphalt or bitumen/butyl rubber sheeting with welded or glued joints. The membrane under the floor slabs has to be lapped with that around the walls. It is essential that the membrane is protected during construction, and a typical arrangement is as shown in Figure 6.15. 

Hot applied mastic asphalt floors have been used for many years in industrial environments, where a good degree of chemical resistance under normally wet conditions is required. Properly laid mastic floors are totally impervious to a wide range of chemicals but not solvents. In terms of mechanical performance, mastic asphalt floors are similar to the bitumen-modified cementitious floors, but they are generally laid at a minimum of 25 mm thickness and tend to shove and corrugate in service under heavy loads. Mastic floors are not very commonly used now, except where the floor is essentially tanked, such as car park decks over shopping precincts. 

Code of Practice No. 4, Safe and Satisfactory Operation of Propane-Fired Bitumen Boilers, Mastic Asphalt Cauldrons/Mixers, and Hand Tools Code of Practice No. 7, Storage of Full and Empty LPG Cylinders and Cartridges Code of Practice No. 9, LPG-Air Plants Code of Practice No. 10, Recommendations for Safe Handling of LPG in Small Trailer Mounted Vessels, Skid Tanks and Small Bulk Storage Vessels Permanently Attached to Mobile Gas-fired Equipment... 

Tapes are produced in both temperate and tropical grades and heavy duty versions can be supplied for application under hot mastic asphalts at field joints of concrete weight-coated pipelines. Wrapping of complex shapes may be achieved by first profiling with a bituminous filler compound. 

Hansen ES Mortality of mastic asphalt workers. Scand J Work Environ Health 17 20-24, 1991... 

Cole P, Green LC, Lash TL. 1999. Lifestyle determinants of cancer among Danish mastic asphalt workers. Regul Toxicol Pharmacol 30 1-8. 

Fig. 5.6 Structure of stone mastic asphalt (SMA), a modern asphalt matrix bonded road surfacing material.

CKD can be added to asphalt binder to produce a low ductile mastic asphalt Mastic asphalt is a mixture of asphalt binder and fine mineral material When mastic asphalt is produced using CKD mixed 50/50 with an asphalt cement binder, a potential exists for a relatively large volume replacement of asphalt cement... 

The European use of mastic asphalts, with low ductility, for bridge deck waterproofing and protection is well documented, and this could represent a potential application for kUn dusts in the United States... 

FHWA (1991) Stone mastic asphalt - SMA - technology synopsis and work plan, draft. Federal Highway Administration, Washington, DC, February 1991, p 452... 

Marblewhite A 325 Marblewhite A 4500 45-55 Mastic Asphalt Filler Micro-White 07 Slurry Micro-White 10 Codex Micro-White 10 Slurry Micro-White 14 Micro-White 14 Slurry Micro-White 15 Micro-White 15 Slurry Micro White 20 Micro-White 25 Micro-White 25 Codex Micro-White 25 Slurry Micro-White 40 Micro-White 50 Codex Micro-White 100 Micro-White 100 Codex Micro-White Superamide No. 1 White ... 

The test is normally performed on fillers that will be used in mastic asphalt applications. However, useful information may be provided for other asphalt performance criteria (Vansteenkiste and Vanelstraete 2008). 

Some countries, such as the United States, England, Germany and France, pioneers in invention and production of asphalts, for many years now, have developed asphalts that are used worldwide. These mixtures were asphalt concrete (AC), macadam, hot rolled asphalt (HRA), mastic asphalt (MA) and gussasphalt. 

Over the last 40 years or more, new mixtures were developed in order to improve some features, such as drainage ability, noise reduction, durability and the ability to be laid in less than a 4 cm thick layer, hence economising on materials. The mixtures developed were porous asphalt (PA) in the United Kingdom, stone mastic asphalt (SMA) in Germany and AC for very thin layers (BBTM) in France. 

Source Reproduced from CEN EN 13108-5, Bituminous mixtures - Material specifications - Part 5, Stone Mastic Asphalt, Brussels CEN, 2008. With permission ( CEN). 

Li Y., Y. Tan, and L. Meng. 2011. Application study on high modulus asphalt concrete in bridge pavement. Advanced Materials Research, pp. 243-249. Switzerland Trans Tech Publications. Mathews D.H. and B.W. Feme. 1970. Trials of the Manufacture and Machine Laying of Mastic Asphalt. 

Because of the geometry of the specimens tested, the test is not applicable to open-graded asphalts or stone mastic asphalts (SMAs). It is appropriate for dense-graded mixtures with 19 mm or smaller nominal maximum aggregate size. 

Other mix characteristics to be tested regardless of asphalt type mixture, according to CEN EN 13108-21 (2008), are void content and, if reclaimed asphalt is used, the penetration and the softening point (R B) of the reclaimed binder. In the case of mastic asphalt, only the indentation on cubes (CEN EN 12697-20 2012) is required to be determined. 

The minimum rolling time depends on the type of material. The minimum rolling time for asphalt concretes and porous asphalts is 20 min, whereas the minimum rolling time for stone mastic asphalt, hot rolled asphalt and mastic asphalt is 30 min. In the case of coated chippings, the minimum rolling time is 10 min. 

The mass of the solvent (tetrachloroethylene), Mp, is 1.6 times the mass of the sample, if the asphalt contains more than 5% binder, or 0.8 times the latter, if it contains less than 5% binder. For mastic asphalt, the mass of the solvent is 4 to 5 times the mass of the sample. 

For the surface layer, in particular, the asphalts most commonly used nowadays are (a) asphalt concrete for very thin layers (AC-VTL), (b) porous asphalt (PA), (c) open-graded friction course mixture (OGFC), (d) stone mastic asphalt (SMA), (e) single or double surface dressing (S-SD or D-SD) and (f) micro-surfacing (MS). Table 10.17 gives the comparative properties/characteristics for all the abovementioned surfacing materials. 

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