ANALYSIS AND EVALUATION OF STIFFNESS AND PERMANENT DEFORMATION OF AC-WC MIXTURES WITH VULCANISED RUBBERISED ASPHALT

• Main Author: Mirza Ariestantiyo, Muhammad
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/73688
• Institution: Institut Teknologi Bandung

<p align="justify"> The asphalt surface layer is an important part of the flexible pavement system. It is the layer that directly contacts the traffic load. One form of damage that can occur from the asphalt surface layer is permanent deformation. Permanent deformation can be caused by several things such as poor compaction, subgrade settlement, and inappropriate viscoelastic properties of asphalt. Modified asphalt is one of the methods used to improve the viscoelastic properties of asphalt, one of which is by using elastomeric additives. One of the elastomeric additives that can be mixed into asphalt is vulcanised natural rubber. Vulcanised natural rubber is natural rubber that has been mixed with a vulcanising agent to strengthen the properties of the rubber itself. Asphalt that has been mixed with vulcanised natural rubber is referred to as vulcanised rubber asphalt. Modified asphalt with elastomers is claimed to provide better resistance to permanent deformation, peeling of the asphalt layer with the aggregate, and resistance to high temperatures when compared to oil asphalt. In this research, the characteristics of PEN 60/70 oil asphalt will be compared with vulcanised rubber asphalt with a variation of 20% and 40% vulcanised material content to the weight of rubber. This research will also test the effect of using vulcanised rubber bitumen in AC-WC mixtures on the Marshall characteristics of the mixture. Then the evaluation of mixture characteristics will also be carried out by testing the resilient modulus with UTM and testing with Wheel Tracking Machine for permanent deformation. The test results of the characteristics of vulcanised rubber bitumen show that vulcanised rubber bitumen has harder characteristics when compared to PEN 60/70 bitumen. In addition, there is also an increase in the rheological properties of vulcanised rubber bitumen marked by an increase in the complex modulus and phase angle of the bitumen. The Marshall characteristics of the AC-WC mix with vulcanised rubber bitumen also showed an improvement where the Marshall stability value of the mix was 1702 kg compared to the Marshall stability value of the AC-WC mix with PEN 60/70 bitumen which was 1198 kg. Testing with UTM showed that the mixtures with vulcanised rubber bitumen had better resilient modulus values than the mixtures with PEN 60/70 bitumen, both at 25°C and 41°C, namely 2522.5 MPa and 964 Mpa for 25°C and 891 MPa and 194 MPa for 41°C. The test results with Wheel Tracking Machine also showed that the mixtures with vulcanised rubber bitumen had better durability than the mixtures with PEN 60/70 bitumen. The permanent deformation value of the mixture with vulcanised rubber bitumen is 4.185 mm while the permanent deformation value of the mixture with PEN 60/70 bitumen is 5.66 mm. In general, the use of vulcanised rubber bitumen as a binder in AC-WC mixtures showed improved performance and mechanistic performance when compared to mixtures with PEN 60/70 bitumen. Vulcanised rubber can be an alternative elastomer modification material for asphalt given the considerable production of natural rubber in Indonesia.