Sensitivity Analysis and A Mathematical Model to Determine The optimum Bitumen Content in Stone Matrix Asphalt

Authors

1 M.Sc. Student, Department of Civil Eng., Yazd University, Yazd, Iran

2 Assistant Prof., Department of Civil Eng., Yazd University, Yazd, Iran

3 Associate Prof., Department of Civil Eng., Yazd University, Yazd, Iran

Abstract

Currently in Iran, the mixing design of stone matrix asphalt mixtures is carried out according to the Marshall method. In Marshall mixing design, the optimum bitumen percentage is determined based on the average amount ​​of the bitumen that leads to the highest Marshall Stability, the highest Specific gravityand the most suitable void percentage in asphalt mixtures with stone matrix asphalt. It doesn’t mean that this bitumen percentage is necessarily the optimum percentage. In this paper, a mathematical model has been developed to determine the optimum bitumen content in stone matrix asphalt by Marshall method, For this purpose, first equations of effective parameters changes in bitumen mix design SMA toward bitumen percent are determined by least squares method and approximating a quadratic polynomial and then relying on these equations and using a multi-purpose mathematical model, optimum bitumen percent is determined in a way that asphalt combination would have all conditions in the code and also would have maximum Marshal stability, the haighest specific gravity and the most appropriate void percentage. After obtaining optimum bitumen content, sensitivity analysis toward very low bitumen percentage on effective parameters (marshall stability, bulk specific gravity of mix asphalt, voids of mix asphalt and voids of aggregate) were done in mix design of stone matrix asphalt. The results of this study indicate that the method of mathematical modeling is more accurate than the traditional method, and sensitivity analysis also showed the effect of error rate on optimum bitumen determination.
 
 
 

Keywords


 
 -فخری، م. و غنی زاده، ع. (1385)، "تعیین درصد بهینه­ی قیر در روش طرح اختلاط مارشال با استفاده از یک مدل
برنامه­ریزی غیرخطی"، پژوهش­نامه حمل­و­نقل، سال سوم، شماره چهارم.
 
 -نشریه شماره 206، (1379)، "طراحی و ارزیابی آزمایشگاهی مخلوط‌های آسفالتی با استخوان‌بندی سنگدانه‌ای (SMA)"، سازمان مدیریت و برنامه‌ریزی کشور، چاپ اول.
 
- Ameri, M., and khani sanij, h., and toolabi, s., and hosseini, s.h., (2012), "optimization of the cold in-place recycling mix design by nonlinear simplex method", transportation research journal, pp.1-9
- Błażejowski, K., (2011), "Stone Matrix Asphalt", Taylor & Francis Group.
 
- Bressi, S., and Dumont, A., and partl, M., (2016), "An advanced methodology for the mix design optimization of hot mix asphalt", Materials and Design, pp. 174-186.
 
- Cao, W., and Liu, Sh., and Feng, Zh., (2013), " Comparison of performance of stone matrix asphalt mixtures using basalt and limestone aggregates", Construction and Building Materials, pp. 474-479.
- Chen, D.H., and Scullion, T., (2015), " Very Thin Overlays in Texas ", Construction and Building Materials, pp. 108-116.
 
- Chiu, Ch., and Lu, L., (2007), " A laboratory study on stone matrix asphalt using ground tire rubber", Construction and Building Materials,
pp. 1027-1033.
 
- Fallon, E., and McNally, C., and, Gibney, A., (2016), " Evaluation of fatigue resistance in asphalt surface layers containing reclaimed asphalt ", Construction and Building Materials, pp. 77-87.
 
- Iskender, E., (2016), " Evaluation of mechanical properties of nano-clay modified asphalt mixtures", Measurement, pp. 359-371.
 
- Khabiri, M.M., (2006), Development of a mathematical model for increasing flexible pavement life cycle under preventive maintenance (Doctoral dissertation, Ph. D Thesis, Iran Science and Technology University).
 
- Lavasani, M., and Latifi Namin, M., and Fartash, H., (2015), " Experimental investigation on mineral and organic fibers effect on resilient modulus and dynamic creep of stone matrix asphalt and continuous graded mixtures in three temperature levels", Construction and Building Materials,
pp. 232-242.
 
- Muniandy, R., and Binti, N.A., and Hassim, S., and Moazami, D., (2014), " Laboratory fatigue evaluation of modified and unmodified asphalt binders in Stone Mastic Asphalt mixtures using a newly developed crack meander technique", International Journal of Fatigue, pp. 1-8.
 
- Nassar, A., and thom, N., and parry, T., (2016), "Optimizing the mix design of cold bitumen emulsion mixtures using response surface methodology", Construction and Building Materials, pp. 216-229.
 
- Thanh, D.V., and Feng, Ch.P., (2013), " Study on Marshall and Rutting test of SMA at abnormally high temperature", Construction and Building Materials, pp. 1337-1341.
- Xie, Zh., and Shen, J., (2016), "Performance properties of rubberized stone matrix asphalt mixtures produced through different processes", Construction and Building Materials, pp. 230-234.