This study was conducted as a part of a research to assess the influence of the volumetric properties of geopolymer artificial aggregates made of fly ash to the performance of asphalt mixture to be used in pavement layers. This paper presents the parameters adopted during the production of geopolymer artificial aggregates which may affect the volumetric properties and the structure of the aggregates. The investigated volumetric properties included specific gravity and water absorption. In the experiment laboratory, two variables were utilized for producing the artificial aggregates, which might affect the considered volumetric properties. Those variables are pan-granulator slopes and alkaline ratios (the ratios of Sodium Silicate to Sodium Hydroxide). The pan-granulator slopes were set at 3 different angles, i.e. 45o, 50o, and 55o. The selected alkaline ratios were 1.5, 2.0, 2.5, and 3.0. The test results indicated that the best volumetric properties were obtained at a slope of 50o and alkaline ratio of 2.5. The bulk specific gravity values at the best volumetric properties were found to be: 1) oven dry at 1.9 grams/cm3; 2) saturated surface dry (SSD) at 2.0 grams/cm3, and 3) apparent at 2.1 grams/cm3 with 6% water absorption. In addition, the interfacial transition zone and microstructure aggregates were examined by using Scanning Electron Microscope (SEM). In this study, it was found that there were effects of Na2SiO3/ NaOH ratios and the granulation method on the volumetric properties.

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The use of natural asphalt is an alternative to meet the high demand for oil asphalt. Asbuton is natural asphalt from Buton Island, Indonesia. However, the use of Asbuton is not as easy as oil asphalt because the asphalt it contains is hard. The asphalt-concrete mixture must go through a rejuvenation process for several days before being compacted. This study aims to determine the performance of asphalt-concrete mixture using Asbuton if it is compacted immediately after mixing, without giving time for the rejuvenation process. Compaction is done when the mixture is hot and after the mixture is cold. Compaction of the asphalt-concrete mixture in hot temperature (150ºC), based on mechanical characteristics (stability, flow, and Marshall Quotient), has better performance than that compacted in cold temperature (30ºC). However, compaction in both hot and cold temperatures, based on their volumetric characteristics, does not meet the requirements for use as road pavements. The performance of the asphalt mixture can be improved by giving time in the process of softening the asphalt content in Asbuton

Tanamori, West Manggarai, East Nusa Tenggara, as a tourism destination area development in Indonesia needs to be supported by the existence of roads as the main means of its development. The road plan is in an area with heavy terrain so it takes a long transportation time. The limited time for completion of work with severe terrain conditions affects the selection of the appropriate type of pavement to be applied. Based on the location conditions and several previous studies, it is necessary to conduct research to determine the type of pavement that is suitable for use. The two types studied are flexible pavement and rigid pavement. The benchmark of the study is based on technical considerations regarding the advantages and disadvantages of applying this type of road pavement in the field. The results showed that flexible and rigid pavements were possible, but based on the difficulty of implementation and execution of the work, rigid pavements were considered more suitable for construction work time. Rigid pavement structure with pavement with 20 cm thick concrete slabs, with joints. D16 T bar for longitudinal joint reinforcement and D33, 450 mm wooden bar for transverse joint reinforcement.

Agregat yang digunakan pada konstruksi perkerasan umumnya menggunakan batu pecah yang didapatkan dari batu gunung maupun sungai yang dapat menyebabkan ketidakseimbangan alam. Oleh karena itu diperlukan agregat buatan yang dapat menggantikan fungsi agregat alami maupun dapat mengurangi penggunaan agregat alami secara signifikan. Penelitian ini bertujuan untuk mengetahui pengaruh variasi penambahan agregat buatan terhadap kadar aspal optimum untuk perkerasan aspal lapis aus. Penelitian ini menggunakan agregat buatan geopolimer berbahan dasar fly ash yang digunakan ke dalam campuran dan dijadikan sebagai pengganti agregat kasar untuk perkerasan lapis aus untuk jalan raya. Variasi komposisi agregat buatan yang digunakan yaitu 0%, 25%, 50%, 75% dan 100%. Terdapat lima sampel untuk masing-masing variasi dengan menggunakan tiga kadar aspal yaitu 5%, 6% dan 7%. Hasil yang didapatkan pada penelitian menunjukkan bahwa kadar aspal optimum untuk variasi penambahan 0% agregat buatan dan 25% penambahan agregat buatan memiliki kadar aspal optimum, sementara untuk variasi penambahan agregat buatan 50%, 75% dan 100% agregat buatan, hasilnya tidak mencukupi syarat spesifikasi yang ada, sehingga tidak dapat ditarik kadar aspal optimum.