Comparative study of performance of natural fibres and crumb rubber modified stone matrix asphalt mixtures

Stone matrix asphalt (SMA) is a gap-graded mix that contains a high concentration of coarse aggregate, thereby maximizing stone-to-stone contact in the mixture and providing an efficient network for load distribution. Coarse aggregate particles are held together by a rich matrix of mineral filler and stabilizer in the thick asphalt film. This paper presents details on the laboratory studies carried out on stone matrix asphalt (SMA) mixtures with natural fibres and crumb rubber modified bitumen (CRMB). Indirect tensile strength, retained stability, resistance to moisture susceptibility, resistance to rutting, resistance to creep, and resistance to permeability and aging were found to improve with SMA mixtures with CRMB when compared with SMA mixtures with fibres as stabilizers.Key words: natural fibres, CRMB, SMA mixtures, draindown, moisture damage, creep, rutting, permeability, aging.

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Effects of Mineral Fillers on Properties of Stone Matrix Asphalt Mixtures

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198196153000111 ◽

1996 ◽

Vol 1530 (1) ◽

pp. 86-94 ◽

Cited By ~ 7

Author(s):

Walaa S. Mogawer ◽

Kevin D. Stuart

Keyword(s):

Testing Machine ◽

Mineral Filler ◽

Moisture Susceptibility ◽

Indirect Tensile Test ◽

Stone Matrix Asphalt ◽

Low Temperature Cracking ◽

Indirect Tensile ◽

Mineral Fillers ◽

Stone Matrix

Stone matrix asphalt (SMA) is a gap-graded hot mixture that has higher proportion of coarse aggregate, lower proportion of middle-size aggregate, and higher proportion of mineral filler than a dense-graded mixture. Because of the high quantity of mineral filler, the type and quantity of this fraction should play a major role in the properties of these mixtures and their mastics. Determination of whether mastic and mixture properties can distinguish good mineral fillers from bad ones is the objective. Eight mineral fillers with known performance were obtained from three European countries. Mastics were tested for stiffness using a bending beam rheometer (AASHTO TP1), a dynamic shear rheometer (AASHTO TP5), and softening point of bitumen using the ring-and-ball apparatus (AASHTO T53-92). None of the tests distinguished among mastics with good and bad mineral fillers. Mixtures were tested for draindown of mastic using the National Center for Asphalt Technology draindown test, rutting using the French pavement rutting tester, low-temperature cracking using the indirect tensile test, workability using the U.S. Corps of Engineers gyratory testing machine, and moisture susceptibility using the ASTM D 4867 method. None of the tests distinguished among SMA mixtures with good and bad mineral fillers.

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Investigation of the fatigue characteristics of warm stone matrix asphalt (WSMA) containing electric arc furnace (EAF) steel slag as coarse aggregate and Sasobit as warm mix additive

Case Studies in Construction Materials ◽

10.1016/j.cscm.2019.e00265 ◽

2019 ◽

Vol 11 ◽

pp. e00265

Author(s):

Mojtaba Alinezhad ◽

Ali Sahaf

Keyword(s):

Coarse Aggregate ◽

Steel Slag ◽

Electric Arc Furnace ◽

Electric Arc ◽

Arc Furnace ◽

Stone Matrix Asphalt ◽

Fatigue Characteristics ◽

Stone Matrix

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Investigation of Stone Matrix Asphalt Mortars

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198196153000112 ◽

1996 ◽

Vol 1530 (1) ◽

pp. 95-102 ◽

Cited By ~ 2

Author(s):

E. Ray Brown ◽

John E. Haddock ◽

Campbell Crawford

Keyword(s):

Resilient Modulus ◽

Heavy Traffic ◽

The United States ◽

Asphalt Pavements ◽

Fine Aggregate ◽

Asphalt Cement ◽

Stone Matrix Asphalt ◽

Initial Application ◽

Indirect Tensile ◽

Stone Matrix

The use of stone matrix asphalt (SMA) has continued to increase in the United States since its initial application in 1991. This preference for SMA has been linked to its ability to withstand heavy traffic without rutting. The antirutting capability of SMA is normally accredited to the presence of a stone-on-stone aggregate skeleton in the mixture. However, the mortar in an SMA mixture is also important. The mortar is composed of fine aggregate, filler, asphalt cement, and a stabilizing additive. Work to characterize SMA mortars is detailed. For testing purposes, the mortar was broken into separate phases, total mortar and fine mortar. The fine mortar was tested using the Superior Performing Asphalt Pavements system (Superpave) binder tests. The total mortar was tested using the bending beam rheometer, resilient modulus, indirect tensile test, and Brookfield vis-cometer. The results indicate that the fine and total mortars are closely related. In addition, it was determined that at least some of the Superpave tests can be used to characterize SMA mortars. It is recommended that further testing be completed and specification criteria be established for the mortar.

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