Effect of Filler Composition on the Performance of Asphaltic Concrete Mixture

• Main Author: Permana Sari, Ayu
• Format: Thesis
• Language: English
• Published: 2008
• Subjects: TA Engineering (General). Civil engineering (General)
• Online Access: http://utpedia.utp.edu.my/8365/1/2008%20Master%20-%20Effect%20of%20Filler%20Composition%20on%20the%20Performance%20of%20Asphaltic%20Concrete%20Mixture.pdf; http://utpedia.utp.edu.my/8365/

Fillers can be used as additive material in bituminous mixtures to minimize distress, such as permanent deformation and fatigue on highway pavements. Fillers with different physical and chemical properties have been found to improve the performance of pavement. However, the exact relationship of specific filler property on the resulting properties of the bituminous mixture has not been clearly defined by previous studies. This study looks at the effect of the physical and chemical properties of filler on the performance of bituminous paving mixtures by correlating the filler properties to permanent deformation and fatigue characteristic of mixture. Three types of filler namely ordinary Portland cement (OPC), quarry dust and fly ash were combined with two types of bitumen i.e. penetration grade 50-60 and 80-100. Each filler was mixed with each bitumen type at filler to bitumen ratios of 0. 75, 1.0 and 1.25 by weight, respectively. Hence, a total of 18 mixtures were prepared. The properties of the prepared bituminous mixture along with optimum bitumen content (OBC) were determined by using Marshall test. The OBC was then used to prepare the specimens for performance test. The performance test includes permanent deformation test using creep and wheel tracking tests, and beam fatigue test to determine fatigue characteristic. The test results show that a spherical particle reduces the percentage of voids and OBC of the mixture, thus improving the performance of the bituminous pavement. Irregular particles were found to increase the consistency of filler-bitumen system and the stability and stiffness of bituminous mixture by its interlocking mechanism. The content of silica and alumina in fillers were found to affect the quality of bituminous pavement by increasing the hardness of the mix and hence the pavement becomes more resistant to permanent deformation. However, increased hardness causes the pavement to brittle faster, therefore, fatigue cracking can occur in early pavement life. The combination of bitumen penetration grade 80-100 mixed with cement in the filler-bitumen ratio 1.0 (80/cmt/1.0) shows the superiority in term of fatigue, whilst the combination of bitumen penetration grade 50-60 mixed with fly ash in the fillerbitumen ratio 1.25 (50/fa/1.25) was the most superior in tem1 of permanent deformation. Key words Mineral filler, asphaltic concrete, permanent deformation, fatigue