Pelucutan adalah mod lazim yang mengakibatkan berlakunya kerosakan turapan di
Malaysia. Ini adalah disebabkan oleh penyusupan air yang berlebihan ke dalam turapan
asfalt lalu mempercepat proses kerosakan pada permukaan dan lapisan bawah turapan.
Tough Fix dan ZycoTherm merupakan bahan anti-pelucutan yang biasanya digunakan di
negara Jepun dan India. Untuk mengatasi masalah pelucutan, Tough Fix dan ZycoTherm
telah digunakan. Selepas tambahan bahan anti-pelucutan, asfalt campuran didedahkan
pada keadaan kelembapan yang berbeza. Kaedah-kaedah kelembapan ini bertujuan
sebagai simulasi kepada keaadaan sebenar di tapak dengan mengambil kira faktor
penuaan dan kelembapan. Kaedah kelembapan terdiri daripada kaedah lazim, kerosakan
akibat kelembapam, perubahsuaian Lottman, percepatan vakum saturator makmal dan
perendaman air. Ciri-ciri kejuruteraan asfalt campuran dinilai dari segi tegangan
kekuatan tidak langsung dan modulus berdaya tahan. Bahan anti-pelucutan di dalam
asfalt campuran telah menunjukkan potensi bagi meningkatkan ketahanan turapan
terhadap kerosakan yang dipengaruhi oleh pelbagai keadaan kelembapan. Meskipun
demikian, ZycoTherm menunjukkan kesan yang ketara di antara bahan anti-pelucutan
yang digunakan. Analisis terhadap agregat pada asfalt campuran juga dijalankan untuk
mengenalpasti punca kehancurannya. Selain daripada bentuk dan kualiti agregat,
orientasi agregat juga merupakan salah satu faktor yang menyebabkan ketidakselarasan
kekuatan tegangan tidak langsung pada asfalt campuran.
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Stripping is the most common cause of pavement distress in Malaysia. This could be
attributed to the excessive infiltration of water into asphalt pavements which accelerate
damage in both surface and subsurface layers. To minimize the problem, Tough Fix and
ZycoTherm, which are currently used in Japan and India as anti-stripping agents and
warm compaction additive respectively, were adopted. Each additive was incorporated
in asphalt mixtures and then subjected to several moisture conditioning methods. To
simulate the actual condition on site, moisture conditioning methods were carried out in
a combination of aging and moisture intrusion. Different levels of moisture conditioning
methods, ranging from unconditioned, moisture induced damage, modified Lottman,
accelerated laboratory vacuum saturator and water immersion; were carried out to
evaluate the engineering properties of asphalt mixtures in terms of indirect tensile
strength and resilient modulus. From the mixture performance test results, mixtures
prepared with ordinary portland cement (OPC), Tough Fix and ZycoTherm showed the
potential to improve pavement resistance to pavement distresses such as moisture
damage, permanent deformation and cracking. The effects of ZycoTherm on the ITSR,
MR, fracture energy, workability, CEI and percentage of adhesive failure; were found to
be significant. Analysis of fractured aggregate was one of the highlights of the study.
Broken aggregates were extracted from the asphalt specimens to investigate the sources
of failure. Apart from poor aggregate shapes such as flaky and elongated particles,
aggregate orientation was one of the factors causing inconsistency of indirect tensile
strength for certain specimens.
Effects of anti-stripping additives on the moisture sensitivity of asphalt mixtures subjected to several conditioning methods / Kam Pui Kuan