The performance of polymer modified bituminous mixtures.

The use of polymers in bituminous materials has been gaining popularity over the last decade. Despite their superiority in enhancing the performance of bituminous mixtures, problems have been experienced due to limitations on the applicability of currently available assessment techniques.This thesis is concerned with the mechanical behaviour of polymer modified bitumens and the performance of polymer modified bituminous mixtures. The first part of the thesis presents different pavement distresses and the importance of using polymer modified binders to improve the performance of bituminous mixtures. The second part deals with identification of properties of polymer modified binders and their mixtures by using dynamic mechanical analysis. The third part attempts to develop a novel technique for assessing resistance to permanent deformation of HRA mixtures using a dissipated energy method.Some polymer modified binders are susceptible to storage instability. However, this work has demonstrated that certain empirical tests are unsuitable for assessing the temperature susceptibility and storage stability of polymer modified binders. Viscoelastic behaviour of bituminous materials is better presented by dynamic mechanical analysis. The dynamic mechanical analysis provides a basis for explaining the unsuitability of some empirical tests on polymer modified binders.Determination of dissipated energy during creep testing enables more comprehensive and accurate assessment of the resistance to permanent deformation of Hot Rolled Asphalt (HRA) mixtures. This study reveals that assessment of the resistance to permanent deformation based upon permanent strain rate in the linear region is in good agreement with the dissipated energy method. The end of the linear region, N1, can be accurately determined by the dissipated energy method and provides a confidence that analysis will always be conducted in the linear region. As expected, polymer modified mixtures are superior to the unmodified ones in their resistance to permanent deformation which confirm by the wheeltracking test, but was not evident from the Marshall tests

Analisis dan Peningkatan Kapasitas Apron di Bandara Halim Perdanakusuma

Penelitian ini membahas tentang peningkatan kapasitas pada Apron di Bandar Udara Internasional Halim Perdanakusuma meninjau dari hasil evaluasi kapasitas apron yang ada saat ini. Penelitian ini bertujuan untuk mengetahui jumlah pesawat yang akan menggunakan apron pada tahun rencana yang kemudian akan ditentukan desain baru untuk apron agar dapat melayani pergerakan pesawat ditahun rencana yaitu tahun 2030. Perancangan ini dilakukan dengan menggunakan 3 skenario yang dibedakan berdasarkan tahun data yang digunakan. Proses dimulai dengan melakukan regresi linear sederhana untuk memperkirakan jumlah pergerakan pesawat dimasa mendatang. Lalu dilanjutkan dengan menentukan nilai Rmonth, Rday, dan Rhour yang kemudian dikalikan dengan nilai hasil regresi untuk mendapatkan nilai Nmonth, Nday, dan Nhour. Nilai Nhour pada tahun rencana dijadikan dasar atau acuan untuk melakukan desain penambahan kapasitas pada apron. Adapun hasil daripada Nhour ditahun rencana pada masing – masing skenario adalah 57 pergerakan untuk skenario pertama, 44 pergerakan untuk skenario kedua, dan 32 pergerakan untuk skenario ketiga. Dengan durasi parking time maksimal 45 menit makan dibutuhkan penambahan parking stand dari 16 parking stand menjadi 43 parking stand untuk skenario pertama, 35 parking stand untuk skenario kedua, dan 24 parking stand untuk skenario ketiga

Damages of orthotropic bridge deck surfacing : forensic investigation, remedial work and performance monitoring

Conventional mastic asphalt typically lasts for more than two decades when being used as bridge surfacing. However substantial increase in heavy goods traffic and higher axle loading has led to some severe cracks in the surfacing during the first ten years since opening to traffic. A forensic investigation into the defects was subsequently carried out. The investigation comprised site inspection, reviewing available records, laboratory testing, designing new surfacing system and recommending remedial actions. The site inspection identified structural and functional damages, which were subsequently assessed in the laboratory on samples taken from site followed by detailed analysis. Laboratory assessments included stiffness, tensile strength and rheology of the existing mastic asphalt surfacing and the waterproofing layer. These suites of testing were followed by Finite Element Models (FEMs) which were developed specifically to analyze movements of the deck, including the cantilever and the main decks, for a range of traffic levels and speeds, considering the mechanical properties determined from the laboratory tests. From the review of literatures and worldwide case studies, three alternative surfacing system options were identified. Prediction of the residual life of the existing surfacing and the projected life of the recommended replacement systems were analyzed. The effect of super single wheel loading on the proposed system was also assessed. Based on the relative performance of these options, recommendations were presented to improve the surfacing design for use in the interim maintenance and remedial works. Follow up works included monitoring the in service performance of the interim solution since opening to traffic. For the future major rehabilitation works, three alternative options have been advised to replace the current surfacing system. The benefits of each of these options have also been presented to assist with decision making, in consideration of the cost and the technical side

Rutting analysis of different rubberised stone mastic asphalt mixtures: from binders to mixtures

Stone Mastic Asphalt (SMA) has been broadly used on heavily trafficked roads and motorways in the UK due to its known stability and durability. In this study, several sets of SMA mixtures were produced using different rubberised bitumens, including a Fischer–Tropsch wax pre-treated rubberised bitumen. Properties associated with rutting were evaluated using both linear and nonlinear viscoelastic analyses, using different test methods such as the Strategic Highway Research Programme (SHRP), Shenoy rutting parameter, zero shear viscosity (ZSV) and multiple stress creep recovery (MSCR) tests. The rutting resistance of the resulting SMA mixtures was assessed using the Repeated Load Axial Test (RLAT). The addition of rubber was expected to enhance rutting resistance of these materials. The results indicated that among the binder rutting parameters assessed, the non-recoverable creep compliance (Jnr) computed from the MSCR test, showed the best correlation with the rutting resistance of the corresponding asphalt mixtures. Finally, a more fundamental analysis was provided by assessing the conditions of binder films that would be experienced in the mixtures