THE TRANSITION TO A PG GRADING SYSTEM FOR ASPHALT CEMENT IN IRAQ
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Abstract
In Iraq, as well as many other developing countries the performance graded (PG) based System is not yet implemented to evaluate the currently used asphalt cernents for paving works. It appears that not only the unavailability of test equipments is resulting in this delay but also the lack of clear understanding of what steps could be taken to incorporate this system. This research is an attempt to highlight the important aspects of a (PG) system that can be readily implemented without the need for expensive equipments. It includes the development of a Performance based System employing the conventional test methods and available nomographs from literature. It also, shows how climatic data, traffic data, and asphalt binder properties can be combined to propose a possible major improvement for the specifications of asphalts in Iraq.
To achieve the objective of this research, an extensive air temperature data for a period of 18 years was reviewed for five cities (Mosul. Kirkuk. Rutba, Baghdad, and Basrah) to establish the required PG asphalt binder for each city. Also, the currently used asphalt cements with penetration grades (40-50) and (60-70) were tested by both of conventional test methods and Superpave methods to determine the equivalent performance grade for each type of the penetration graded asphalt and to evaluate the capability for these two types of asphalt cement to satisfy the required performance of pavement for each city, The results indicate that both the new proposed method and Superpave method give the same final performance grade. The asphalt with penetration grade 40-50 is equivalent to PG70-16 while that with penetration grade 60-70 is equivalent to PG64-16
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References
AASHTO, (2007), "Standard Specifications for Transportation Materials and Methods of Sampling and Testing", 5th edition, American Association of State Highway and Transportation Officials, Washington, D.C., USA.
Abbas, F., (2006), "Evaluation of Contributory Factors Influencing Permanent Deformation of Asphalt Paving Materials", M.Sc Thesis, Al-Mustansiriya University.
Al-Abdul Wahhab, H.I Al-Dubabe, I A., Asi, IM., and Ali, M.F.. (1998), "Performance Based Characterization of Arab Asphalt", journal of building and environment, Kingdom of Saudi Arabia, Vol.33, PP375-383.
Alani, H.M., (1986). "Temperature Susceptibility of Paving Grade Asphalt Cements"Engineering and Technology. Scientific Journal Published by University of Technology. Baghdad, Vol.4, No.2
Alaredı, H.A., (2006), "Reduction of Reflection Cracks in Overlay of Rigid Pavements" M.Sc. Thesis, Al-Mustansiriya University.
Alszawy, N.M., (2006), "Comparative Evaluation for the Performance of Paving Materials by Using Marshall and Superpave Compaction Methods M.Sc Thesis, Al-Mustansiriya University.
Albayatı, A.H. (2006). "Permanent Deformation Predictions of Asphalt Concrete Under Repeated Loading" Ph.D. Thesis, Baghdad University. Alekaby, K.H... (2005)." The Frictional Properties as a Design Control of Pavement Surface Mixtures M.Sc Thesis, Baghdad University.
Aljumily, M.A., (2007), "Influence of Aging on Performance of Asphalt Paving Materials" Ph.D Thesis, Baghdad University.
Almudhadi, T.H., (2007), "Some Requirements to Control Reflective Cracking of Overlay Asphalt Pavement" Ph.D. Thesis. Baghdad University. Asal, F.N. (2007), "Fatigue Behavior of Flexible and Rigad Pavements under Cyclic Loads",Ph.D. Thesis, Baghdad University Asi, IM. (2007). "Performance Evaluation of SUPERPAVE and Marshall Asphalt Mix Designs to Suite Jordan Climatic and Traffic Conditions", journal of construction and building materials, Vol 21, PP.1732-1740.
Asphalt Institute, (2003), "Performance Graded Asphalt Binder Specification and Testing". Manual Series No.1, (SP-1), Asphalt Institute, Lexington, Kentucky.
Bahia H.I. and Vivanco J., (2005). "The Transition to a PG Grading System for Asphalt Binders in Developing Countries", University of Wisconsin, Madison.
Hanaa, K., (2004), "Minimizing Reflective Cracking Potential of Asphalt Concrete Overlay". M.Sc. Thesis, AL-Mustansiriya University.
Heukelom, W., (1973). "An Improved Method of Characterizing Asphaltic Bitumens with the Aid of Their Mechanical Properties". Proceedings of the Association of Asphalt Paving Technologists, USA, Vol.42, pp 67-98.
Iraq Metrological Organization, (1989), "Climatic Atlas of Iraq 1951-1980", Baghdad. Republic of Iraq Mand Aldeen. A. (2003), "Evaluation of The Factors Influencing The Tensile Properties of Asphalt Paving Materials", M.Sc. Thesis, Baghdad University
McLean, D.B., (1974), "Permanent Deformation Characteristics of Asphalt Concrete", Ph.D.Dissertation, University of California, Berkeley. Nahla, Y.A., (2005), "Prediction Model of Rutting Potential in Flexible Pavements.", Ph.D. Thesis, Baghdad University.
Namir, G.A., (2002). "The Development of Models for the Prediction of Thermal Cracking in Flexible Pavements." Ph.D. Thesis, Baghdad University.
Safar, M.M., (1992), "Influence of Temperature on Performance of Paving Materials.", M.Sc Thesis, Baghdad University.
Shakır, S., (1999), "Contributory Factors Related to Rutting of Local Asphalt Pavements." M.Sc. Thesis, Baghdad University
Shell, (1978), "Sheil Pavement Design Manual Asphalt Pavement and Overlays for Road Traffic". Shell International Petroleum, London
SHRP, (1994), "The Superpave Mix Design Manual for New Construction and Overlays", Strategic Highway Research Program Report No SHRP-A-407, National Research Council,Washington, D.C. USA.
Taher. M.H., (1999), "Influence of Accelerated Weathering of Asphalt Cement on Performance of Paving Materials." M.Sc Thesis, Baghdad University.
Van der Poel. (1954), "A General System Describing the Viscoelastic Properties of Bitumens and Its Relation to Routine Test Data", Journal of Applied Chemistry, Vol 4.
Van de Van, M.F.C., Jenkins, KJ, and Bahia, HU, (2004), "concepts used for development of bitumen specifications" Proceeding of the Conference on Asphalt Pavements for Southern Africa
Zaid. 1. (2006). "Superjave Mineral Aggregate Properties as Related to Moisture Sensitivity of Paving Mixtures M.Sc. Theus, Haghdad University