PERFORMANCE OF WARM MIX ASPHALT (WMA) MIXTURE USING NANOCLAY MODIFIED ASPHALT BINDER MOHD EZREE BIN ABDULLAH A thesis submitted in fulfilment of the requirements for the award of the.," Degree of Philosophy Faculty of Civil and Environmental Engineering Universiti Tun Hussein Onn Malaysia MAY 2014
ABSTRACT Going towards green pavement construction, asphalt concrete industries consistently make effort to implement Warm Mix Asphalt (WMA). The aim of this research was to establish the WMA mixture using nanoclay modified binder according to Superpave mix design method. It started by modisring the PG 64-28 asphalt binder with different percentages of Nanoclay A, Nanoclay B and Chemical warm asphalt additives. After modification, the modified binders were categorised as Nanoclay A Modified Binder (NCMB A), Nanoclay B Modified Binder (NCMB B) and Chemical Warm Asphalt Modified Binder (CWAA). The rheological characteristics of binders were evaluated using the SuperpaveTM rotational viscosity, dynamic shear rheometer, and bending beam rheometer test. The results indicated that NCMB B and CWAA significantly reduced mixing and compaction temperature. However, only NCMB B shows a significant incpse in rutting and fatigue resistance when compared to the virgin binder. In addition, the chemical bonding had changed in the tested binder after long term aging which suggest that the addition of modifier could delay the aging process. A total of 260 specimens were prepared to evaluate and compare the engineering properties of hot mix asphalt (HMA) and WMA mixtures using NCMB B and CWAA. Based on statistical analysis, it was observed that WMA mixtures produced at 30 C lower than conventional HMA for both modifiers showed a significant emissions reduction and have no significant difference on performance in term of rutting, fatigue, moisture susceptibility and resilient modulus (MR). Studies on correlation and regression analysis between various rheological modified asphalt binder and engineering properties of WMA mixtures containing NCMB B and CWAA were also conducted. It was found that a strong correlation exists between G*/sin 6 and rut depth. In conclusion, the introduction of NCMB I3 has a bright potential as a new environmentally WMA binder in future.
ABSTRAK Menuju ke arah perlaksanaan pembinaan turapan hijau, industri konkrit berasfalt telah melaksanakan usaha yang berterusan untuk melaksanakan teknologi campuran asphalt suam (WMA). Matlamat kajian ini adalah untuk menghasilkan campuran WMA yang mengandungi bahan pengikat yang diubahsuai dengan tanah liat nano dengan menggunakan reka bentuk campuran berdasarkan kaedah Superpave. Kajian ini dirnulakan dengan mengubahsuai pengikat asfalt gred PG 64-28 dengan Tanah Liat Nano A, Tanah Liat Nano B dan bahan tambah asphalt sum jenis kimia pada peratus yang berbeza. Setelah pengubahsuaian, pengikat terubahsuai itu dikategorikan sebagai pengikat terubahsuai Tanah Liat Nano A (NCMB A), pengikat terubahsuai Tanah Liat Nano B (NCMB B) dm pengikat terubahsuai asphalt suam jenis kimia (CWAA). Ciri-ciri reologi pengikat-pengikat diuji dengan menggunakan kaedah berasaskan standard SuperpavgM iaitu ujian kelikatan putaran, reometer ricih dinamik, dan ujian reometer rasuk lenturan. Keputusan menunjukkan bahawa NCMB B dan CWAA secara siknifikan telah berupaya mengurangkan suhu pencampuran dan pemadatan. Walaubagaimanapun, hanya NCMB B menunjukkan peningkatan yang signifikan untuk ujian rintangan aluran dan rintangan lesu berbanding pengikat kawalan. Selain itu, ikatan kimia dalam pengikat yang diuji telah berubah sifatnya selepas penuaan jangka panjang dan ini menunjukkan penggunaan bahan pengubahsuai mampu melarnbatkan proses penuaan. Sebanyak 260 spesimen telah disediakan untuk dinilai dan dibandingkan ciri-ciri kejuruteraan antara carnpuran asphalt panas (HMA) dengan campuran WMA dengan menggunakan NCMB B dan CWAA. Berdasarkan analisis secara statistik, didapati bahawa campuran WMA yang dihasilkan pada suhu 30 C lebih rendah daripada campuran konvensional HMA untuk kedua-dua jenis pengubahsuai telah menunjukkan pengurangan tahap pencemaran dan prestasinya pula tidak mempunyai perbezaan yang signifikan dari sudut aluran, kelesuan, rintangan kelembapan dan modulus kekukuhan (MR). Kajian korelasi dan analisis regresi antara pelbagai parameter reologi pengikat asphalt yang
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