| Summary: | Efforts to obtain natural material to be used as pavement materials is
wanted. However, besides the large requirement of deposits, material should also
be able to provide specific parameters required. This research attempts to exploit
the material bantak of which wear and absorption rate below the standard. By this
research, the properties of this material will be tried to be improved to meet the
specific requirement.
Research is carried out by making coarse aggregate design covered by
Buton Granular Asphalt (BGA) and added with fluxing asphalt. The fluxing
asphalt will be tested for its levels of wear and absorption which is then served as
a coarse aggregate in hot mix asphalt HRS-Base. To obtain the optimum asphalt
content, 5 different specimens are created with asphalt content at 5%, 5.5%, 6%,
6.5%, and 7%. All the specimens are examined with the properties of Marshall.
The next step is testing the durability and tensile strength of asphalt.
The results showed bantak coarse aggregate abrasion value�s of 69.23%
decrease to 32.5% while the value of the original absorption of 4.86% decrease to
2.63%. From the Marshall test, it can be seen that density values increase with the
addition of bitumen. Similar thing happens to the VFWA value, but only
specimens with binder content of 6.5% and 7% are eligible. For VMA value, all
the specimens still meet specification required, while the value of VITM only
specimen with of 6.5% asphalt content are eligible. Stability value of all
specimens grows beyond the required minimum value, so does the Marshall
Quotient value. From the average value of the Marshall Properties, optimum
asphalt content is obtained. It is 6.65%. Durability testing shows that this mixture
has Index of Retained Marshall of 91.5%. This figure meets the minimum
specification required, 80%, with the most appropriate specimen is the number 3.
The value of Tensile Strength Ratio (TSR) from specimen with 24 hours of
immersion and specimens without immersion is 81.27%. It meets the minimum
requirement of TSR which 80% (Asphalt Institute, 1996).
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