Mechanical Performance of Stone Mastic Asphalt Incorporating Steel Fiber

Stone Mastic Asphalt (SMA) is a gap-graded hot mixture designed to provide higher resistance towards permanent deformation and rutting potential by 30% to 40% more than dense-graded asphalt, due to its stable aggregate skeleton structure. However, compared to other types of hot mix asphalt, SMA unfortunately has some shortcomings in term of its susceptibility towards moisture-induced damage due to its structure and excessive bitumen content in the composition. This research aims to assess the performance of a SMA mixture with steel fiber by enhancing overall stability, abrasion resistance, and, most importantly, moisture susceptibility. This study involved the incorporation of various steel fiber proportions of 0%, 0.3%, 0.5% and 0.7% by the total weight of mixture. The steel fiber modified SMA was made up of 6.0% PEN 60/70 bitumen content. The performance of SMA were evaluated through Marshall stability and flow test, Cantabro loss test and indirect tensile strength test. The results obtained from the testing showed that the incorporation of steel fiber is significantly effective to enhance the resistance towards moisture damage, while increasing the stability and reducing the abrasion loss of SMA mixture, compared to conventional mixture. Overall, it can be concluded that the addition of steel fiber in asphalt mixture specifically SMA, has improved the mechanical performance in the application of asphalt pavement with the optimum steel fiber proportion of 0.3% by the weight of mixture. The developed models between the independent variables and responses demonstrated high levels of correlation. The study found that Response Surface Methodology (RSM) is an effective statistical method for providing an appropriate empirical model for relating parameters and predicting the optimum performance of an asphaltic mixture to reduce flexible pavement failure.

Download Full-text

Statistical Analysis of Stone Mastic Asphalt Incorporating Kenaf Fibre

CONSTRUCTION ◽

10.15282/construction.v1i1.6282 ◽

2021 ◽

Vol 1 (1) ◽

pp. 12-17

Author(s):

G. Danoshini ◽

A. Baqadeem ◽

A. K. S. Al-Shakhrit ◽

N. E. Jasni ◽

Khairil Azman Masri

Keyword(s):

Statistical Analysis ◽

Mechanical Performance ◽

Natural Fiber ◽

Positive Impact ◽

Fiber Composite ◽

Permanent Deformation ◽

Kenaf Fiber ◽

Physical Strength ◽

Mastic Asphalt ◽

Stone Mastic Asphalt

Stone mastic asphalt consists of two components of coarse aggregate and bitumen-filled mortar (bituminous blend, filler, and stabilizing additives like cellulosic or mineral fibers). Such a form of hot mix asphalt (SMA) was first developed in Germany in the mid-1960s to cope with corrosion and ribbed wheel destruction. The mixture was then known as stone mastic asphalt, which was not only immune to ribbed wheels but also has strong resistance against rutting. One of the most significant problems when constructing the stone mastic asphalt pavement is permanent deformation. By a load of traffic and the strain of the tires, much of the irreversible deformation happens in the ground. According to a previous study, researchers have stated that the kenaf fiber's physical strength and thermal characteristics are superior compared to other forms of natural fiber polymer composites, and therefore deemed a desirable applicant for elevated-performance natural fiber composite materials. Thus, the aim of this study is to assess the mechanical performance of stone mastic asphalt incorporating kenaf fiber by developing a regression model. A set of data of SMA mixture incorporating various percentages of kenaf fiber were assessed through statistical analysis in Minitab 19 by using the resilient modulus as the dependant variable in the first model and the accumulated strain from the dynamic creep test as the dependant variable in the second model. The regression models showed a positive impact of kenaf fiber as an additive in the SMA mixture. For more future studies, it is recommended to analyze the effect of the various proportions of kenaf fiber with bitumen modification towards stone mastic asphalt performance that will render the satisfactory performance of SMA during service.

Download Full-text

Performance Evaluation of Styrene-Butadiene-Styrene-Modified Stone Mastic Asphalt with Basalt Fiber Using Different Compaction Methods

Polymers ◽

10.3390/polym11061006 ◽

2019 ◽

Vol 11 (6) ◽

pp. 1006 ◽

Cited By ~ 11

Author(s):

Wensheng Wang ◽

Yongchun Cheng ◽

Peilei Zhou ◽

Guojin Tan ◽

Haitao Wang ◽

...

Keyword(s):

Mechanical Performance ◽

Asphalt Binder ◽

Basalt Fiber ◽

Pavement Performance ◽

Volumetric Properties ◽

Mastic Asphalt ◽

Stone Mastic Asphalt ◽

Styrene Butadiene Styrene ◽

Styrene Butadiene ◽

Butadiene Styrene

Superpave gyratory compaction (SGC) and Marshall compaction methods are essentially designed according to volumetric properties. In spite of the similarity, the optimum asphalt contents (OAC) of the two methods are greatly affected by the laboratory compaction process, which would further influence their performance. This study aims to evaluate the performance of styrene-butadiene-styrene (SBS)-modified stone mastic asphalt (SMA) with basalt fiber by using SGC and Marshall compaction methods. Basalt fiber was proved to improve and strength the basic properties of SBS-asphalt according to test results of asphalt binder. The effects of SGC and Marshall compaction methods on OAC and volumetric properties, i.e., density, air voids (VA), voids in mineral aggregates (VMA), and voids filled with asphalt (VFA), were evaluated in detail. Finally, the pavement performance of asphalt mixture prepared by SGC and Marshall compaction methods were compared in order to analyze the high-temperature creep, low-temperature splitting, and moisture stability performance. Results showed that the OAC of SGC (~5.70%) was slightly lower than that of Marshall method (5.80%). Furthermore, the pavement performance of SGC specimens were improved to a certain extent compared with Marshall specimens, indicating that SGC has a better compaction effect and mechanical performance.

Download Full-text

Effect of Nano Hydrotalcite on the Aging Resistance of a High Binder Content Stone Mastic Asphalt

Applied Sciences ◽

10.3390/app11219971 ◽

2021 ◽

Vol 11 (21) ◽

pp. 9971

Author(s):

João Crucho ◽

José Neves

Keyword(s):

Mechanical Performance ◽

Asphalt Mixture ◽

Surface Characteristics ◽

Binder Content ◽

Barrier Effect ◽

Mastic Asphalt ◽

Aging Resistance ◽

Stone Mastic Asphalt ◽

Double Hydroxide

Hydrotalcite, a type of layered double hydroxide (LDH), reveals an interesting potential for the modification of bitumen. The LDH can induce a barrier effect that prevents the loss of volatiles, retards oxidation, and protects against ultraviolet radiation. Such properties can enhance the aging resistance of the bitumen. However, there is a gap in knowledge regarding the effects of the modification with hydrotalcite in the properties of the asphalt mixture. To contribute to fill such a gap, the current study presents a characterization of the effects of the modification with nano hydrotalcite in the surface characteristics, mechanical performance, and aging resistance of an asphalt mixture. To better explore the effects of the modification, the selected asphalt mixture was a high binder content (7.5%) Stone Mastic Asphalt (SMA). The experimental study indicates that the binder-rich SMA presented adequate performance for application in surface courses. If compared to conventional mixtures, the binder-rich SMA presented better initial mechanical performance (unaged conditions). Furthermore, it presented smaller variation in the parameters between unaged and aged conditions, indicating enhanced aging resistance. The modification with nano hydrotalcite induced smaller evolution in the fatigue resistance parameters, indicating enhanced aging resistance; however, in the remaining tests, the trends were not clear.

Download Full-text