Document
Estimating optimum compaction level for dense-graded hot-mix asphalt mixtures.
Contributors
Mohammad, Louay N., Author
Publisher
Sultan Qaboos University
Gregorian
2010
Language
English
English abstract
A critical step in the design of asphalt mixtures is laboratory compaction. Laboratory compaction should reflect field compaction and should produce mixtures that are economical and possess high structural stability. During the compaction process, asphalt mixtures are subjected to certain amount of compaction energy in order to achieve the required density. The Superpave volumetric mix design is based on compacting HMA mixtures to a specified compaction level described by the number of gyrations from the Superpave gyratory compactor (SGC). This level is termed Ndes and represents the required energy (based on the traffic level expected) to densify the mixture to a 4% air voids level. This paper re-examines the Superpave compaction requirements through extensive laboratory investigation of the response of a number of asphalt mixtures to the applied compaction energy. It also presents an alternative method to estimate the number of gyrations at which a mixture first reaches an optimum aggregate interlock and hence prevents overcompaction problems that might result in unstable aggregate structures or dry asphalt mixtures. A total of 12 HMA mixtures were studied. During compaction, force measurement was made using the pressure distribution analyzer (PDA). The compaction characteristics of the mixtures were analyzed using data from the PDA and the traditional Superpave Gyratory Compactor (SGC) results.
Member of
ISSN
1726-6742
Resource URL
Citation
Al-Shamsi, K., & Mohammad, L. N. (2010). Estimating optimum compaction level for dense-graded hot-mix asphalt mixtures. The Journal of Engineering Research, 7 (1), 11-21.
Arabic abstract
يعد الدمك (الضغط) المخبري من الخطوات الأساسية في تصميم الخلطات الاسفلتية. الدمك المخبري ينبغي أن يؤدي إلى إنتاج عينات اسفلتية ذات خصائص هندسية مشابهة للمادة الاسفلتية الناتجة من الدمك الذي تحدثه معدات الضغط المستخدمة في تشييد الطريق. هذه الدراسة تقدم طريقة مبتكرة لتحديد المستوى الأمثل للدمك المخبري للخلطات الاسفلتية ذات الكثافة العالية وذلك باستخدام فحوصات مخبرية متطورة. الدراسة شملت تصميم وتحليل خصائص 12 خلطة اسفلتية مختلفة وأيضا الاستعانة بجهاز متطور القياس توزيع الضغط داخل العينة أثناء الدمك.
Category
Journal articles