Malaysia merupakan sebuah negara tropika yang mempunyai keamatan hujan yang tinggi. Kebanyakan permukaan jalan raya di Malaysia dibuat daripada bahan tidak telap air. Masalah seperti percikan dan semburan di belakang kenderaan yang bergerak, pantulan dari lampu depan kereta dan silau pada permukaan basah kerap berlaku. Untuk membanteraskan masalah ini, asfalt berliang diperkenalkan. Asfalt berliang mengurangkan kesan „hydroplaning‟ dan meningkatkan rintangan gelincir pada permukaan jalan raya terutamanya semasa musim hujan. Namun, asfalt berliang selalu menghadapi masalah “ravelling” dan penyumbatan liang. Kajian ini membentangkan kesan kemasukan sela ke dalam penggredan Belanda dan penggredan cadangan. Agregat yang bersaiz dari 2.00 mm hingga 5.60 mm dikeluarkan dalam penggredan Belanda. Bagi penggredan cadangan, agregat yang bersaiz dari 2.36 mm hingga 5.00 mm dikeluarkan and dua jenis penggredan dicadangkan dengan peratusan agregat saiz yang berbeza. PG1 mempunyai peratusan agregat halus yang lebih tinggi manakala PG2 mempunyai peratusan agregat kasar yang lebih tinggi. Ciri kejuruteraan asfalt berliang yang mempunyai sela pada agregat penggredan ditentukan melalui ujian kebolehtelapan, ujian “Cantabro”, ujian kekuatan ketegangan dan ujian “Semi-circular Bending”. Keputusan analisis statistik menunjukkan lompang udara dan pekali kebolehtelapan meningkat jika sela diperkenalkan. Pekali kebolehtelapan daripada PMG1 tidak menunjukkan peningkatan yang ketara selepas sela pengredan dimasukkan kerana PMG1 mempunyai peratusan agregat halus yang lebih tinggi. Sementara itu, kekuatan ketegangan, rintangan terhadap kehilangan lelasan and keliatan patah tidak menunjukkan kesan ketara ketika sela dimasukkan. Namun, ITS daripada PMG2 menunjukkan kekurangan yang ketara selepas sela dimasukkan.
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Malaysia is a tropical country and experience high rainfall intensity. Most of Malaysian roads are made from impermeable pavement. Problems related to hydroplaning effect, splash and spray, headlight reflection and glare on wet surface are a common occurrence. To minimize these problems, porous asphalt was introduced. Porous asphalt reduced the hydroplaning effects and improved the skid resistance during rainy season. However, these positive characteristics tend to deteriorate during their service life due to stripping, ravelling and clogging. In this study, the effects of introducing a gap in the Dutch gradation and proposed gradation were investigated. For the Dutch gradation, a gap was introduced at sieve size passing 5.60 mm but retained on 2.00 mm and named as DG. Then for the proposed gradation, a gap was introduced at sieve size passing 5.00 mm but retained on 2.36 mm. Two proposed gradations, namely PG1 and PG2 were proposed and mainly different in terms of their percentage of passing. PG1 has higher percentage of fine aggregates while PG2 has higher percentage of coarse aggregates. The engineering properties of porous asphalt were determined through the permeability, Cantabro, indirect tensile strength, and semi-circular bending tests. The statistical analysis results showed the air voids and coefficient of permeability increased as the gap was introduced. However, PMG1 do not show any significant increment in the coefficient of permeability due to high percentage of fine aggregates. Generally, the ITS, abrasion loss and fracture toughness do not show any statistical significant different when the gap was introduced. However, PMG2 showed significant reduction in ITS after the gap was introduced.
Effects of introducing gap in the fine aggregate gradation on properties of porous asphalt mix_Wong Tau Kie_A9_2011_875004074_00003089630_NI