Pavement design with mechanistic approach has been rapidly developed since the last three decades. Since 1970's bituminous mixes characteristics has been understood better with the discovery of testing equipment(s), such as Direct Shear Rheometer (DSR) and Universal Material Testing Apparatus (UMATTA) that can directly determined the modulus of asphalt and mixes. Some models also parallelly developed for the same purposes which are determining asphalt stiffness modulus (S bit ), such as: Van der Poel Nomogran, and Ullidtz, formula and mix stiffness modulus (S mix ), such as: Bonnaure et.al (1977), Asphalt Institute (1982 and Nottingham (Brown, et. al. 1984). Within the frame of thinking of improving asphalt material performance with local modifier, the research aims to evaluate the suitability of the model to examine the result for mixes with pure (fully extracted) asbuton of asphalt binder. The modification that expectly could improve S bit and S mix was done with adding 8% by weight of pure asbuton to the Pen grade asphalt in wearing course mix. The research result is hopefully could give significant contribution to the asbuton research in term of model suitability indication, that originally used pen grade, to predict the value of S bit and S mix within the mix of wearing course that used the pure asbuton modified asphalt.

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The limitations of road construction materials require alternative materials such as asphalt recycling and utilization of waste potential such as steel slag for aggregate substitutes. In this study, there were tests for slag characteristics and reclaimed asphalt pavement (RAP) then continued with a marshall test to determine the optimum asphalt content (OAC). The nine mixtures planned in this study consist of 10-30% Slag combined with 10-30% RAP with Reclamite as a rejuvenating material. Using a combination of RAP, there is a decrease in the mixing and compaction temperature of 20°C compared to the conventional hot mix. Test results on hot mix asphalt using a combination of RAP and slag generate an increase of 10-30% each using a combined gradation and volume correction.

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Warm Mix Asphalt (WMA) adalah campuran beraspal yang diproduksi pada suhu 20-40°C lebih rendah dari HMA. Zeolit merupakan salah satu bahan tambah WMA dengan memanfaatkan kemampuan zeolite membawa air dan melepaskannya pada suhu tinggi sehingga terjadi pembusaan pada aspal yang dapat meningkatkan volume aspal. Selain zeolit sintetis, zeolit alam juga dapat digunakan sebagai aditif. Sebelum digunakan, zeolit alam perlu diaktivasi untuk menghilangkan unsur pengotor, merubah rasio Si/Al, dan meningkatkan penyerapan air. Metode penelitian berupa percobaan di laboratorium dengan proses aktivasi menggunakan larutan asam HCl dan larutan basa NaOH. Variasi ukuran butiran zeolite 75 m (#200) dan 38 m (#400). Sebagai pembanding digunakan zeolite sintetik merek Aspha-min. Hasil penelitian menunjukkan aktivasi zeolite alam dengan NaOH memiliki nilai rasio Si/Al yang lebih kecil dan kadar air yang lebih besar, yaitu 15.65%, (masih di bawah zeolite sintetik dengan kadar air 19.77%). Ekspansi volume aspal terjadi pada suhu 30 0 C di bawah suhu HMA dengan penambahan zeolite. Peningkatan kadar zeolite meningkatkan faktor ekspansi aspal dan memperkecil waktu ekspansi. Faktor ekspansi aspal dengan penambahan zeolite alam berada di bawah zeolite sintetik, hal ini disebabkan karena kadar air yang lebih kecil dari pada zeolite sintetik