Mohd Ezree Abdullah

Rheological Properties of Asphalt Binder Modified with Chemical Warm Asphalt Additive

Going towards sustainable pavement construction, asphalt industries constantly give their effort to implement Warm Mix Asphalt (WMA) by adding the chemical warm asphalt additive (CWAA). This can lower its energy consumption and pollution by reducing the mixing and compaction temperatures of the asphalt mixture without affecting its properties. Several studies have been conducted evaluating the properties of the WMA, however, little documented research on the rheology of the binders containing CWAA is available especially when dealing the sources of binders. In this paper, the tests for rheology characteristics of the Malaysian asphalt binder containing CWAA were conducted with rotational viscosity and for dynamic mechanical analysis with dynamic shear rheometer (DSR). The results of the investigation indicated that the CWAA had a significant reduction of required heat for mixing and compaction effort and also shows lower permanent deformation when compared to the control binder.

Effect of Aging on Resilient Modulus of Hot Mix Asphalt Mixtures

Asphalt hardens as a result of an aging process. This study was undertaken to determine the effect of field aging simulated by laboratory aging method of different hot mix asphalt (HMA) mixture. Three types HMA mixtures were used for this study namely Asphaltic Concrete with 10 mm nominal maximum aggregate size (AC 10), Aspaltic Concrete 28 mm (AC 28) and Porous Asphalt 10 mm (PA 10). The resilient modulus test was carried out as an indicator of the performance at a 25 °C and 40 °C. Generally, all samples show similar trend which aged mixture produced slightly higher resilient modulus compared to unaged mixture while an increase in temperature from 25 °C to 40 °C might reduced the resilient modulus up to 88%. This study also found that the difference increment of resilient modulus after the aging process attributed by asphalt content, air void and gradation of respective mixtures.

Short term and long term aging effects of asphalt binder modified with montmorillonite

Nowadays, most of asphalt used in pavement construction is produced from petrochemicals through refining process of crude oil. When evolves with time, asphalt become stiffer and brittle due aging process. In this paper, the rheological effect of short-term and long-term oxidative ageing of asphalt binder modified with montmorillonite (MMT) was studied using SuperpaveTM rotational viscometer (RV), dynamic shear rheometer (DSR) and Fourier transform infrared (FTIR) instruments. The results indicate the addition of MMT increased the viscosity. Based on dynamic mechanical analysis with DSR, MMT modified binder has a potential to increase rutting and fatigue resistance. In terms of FTIR test, it appears that the chemical bonding had changed in the asphalt binder before and after RTFO and PAV aging which suggest that the additional of MMT could delay the aging process.

Rutting Evaluation of Aged Binder Containing Waste Engine Oil

The stiffness of aged binder is highly contributed to the workability problem. Rejuvenating agent such as waste engine oil (WEO) is one of the sustainable modifiers that can be used to improve and attain the desired performance of the aged binder. However, concern arises on the consistency of the engine oil properties due to its unknown history usage. This study focused on the rutting properties evaluation of the partial aged binder integrating with engine oil (new and waste sources) using Dynamic Shear Rheometer (DSR). The findings showed that, the addition of WEO affects the rutting performance under ageing condition. From the isochronal curve, the complex modulus, G* of the rejuvenated binder was found lower than the aged binder at un-aged condition. However, after ageing process, the stiffness of the rejuvenated binder was increased and the phase angle, δ decreased obviously compared to virgin binder. The critical temperature of the binder was not differing substantially particularly under ageing. Meanwhile, the ageing index rutting factor (AIRF) clearly summarised that the rejuvenated binder with WEO with higher mass loss more susceptible to ageing.

Dynamic Load Coefficient of Tyre Forces from Truck Axles

This study aims to predict the Dynamic Load Coefficient (DLC) of tyre forces from truck axles. Dynamic Load Coefficient is frequently used to characterise the dynamic loads generated by axles. It is a simple measurement of the dynamic variation magnitude of the axle load, for a specific combination of road roughness and speed. Under normal operating conditions, the DLCs value is typically in the range of 0.05-0.3, and close to zero when the trucks wheels are moving over a perfectly smooth road. To achieve the objectives of this study, which is to determine the DLCs value for seven different types of axles, a simple validated quarter-truck model was excited by a random road surface profile, in order to simulate a vehicle-road interaction. Points are equally spaced along the simulated road to generate dynamic loadings over a broad range of truck speeds. Multiple trucks gross-weight conditions were used to present realistic traffic behaviour. The results showed that irregular road profiles, exciting the vehicle as it travelled, caused continually changing tyre forces. Also, dynamic loading was seen to be fundamentally influenced by the type of suspension (i.e., air and steel), loading condition, and vehicle speed. For example, the DLC value of the tyre forces of the quarter-truck fitted with a steel suspension was found to be more than twice that of the truck fitted with an air suspension. Tyre forces of the one-third laden truck were more aggressive than any other loading condition, due to the uncertain body-bounce generated by the truck, which was strongly dependent on surface irregularities. At low speed, the DLC was greatly decreased if the load was increased. Furthermore, DLC value was always lower for trucks with air suspension over steel suspension, for the same load and vehicle speed. However, air suspension efficiency was clearly better for higher axle loads.

Physical properties and storage stability of asphalt binder modified with nanoclay and warm asphalt additives

Nowadays, researchers are interested in using the material at nanoscales as one of asphalt binder modifier. In this paper, Malaysian asphalt binder was modified with nanoclay and warm asphalt additives (WAA) and tested to determine the physical properties and storage stability. The results of the investigation indicated that the modified asphalt binders were stable in term of storage and they also have potential to improve physical properties of asphalts such as increasing softening point and decreasing the penetration. In addition, there was a significant reduction of temperature for mixing and compaction of asphalt mixtures.

A review of using porous asphalt pavement as an alternative to conventional pavement in stormwater treatment

Purpose Porous asphalt has been used for than 50 years, but it was originally developed in 1970 at Franklin institute in Philadelphia, Pennsylvania. By 1974 the first formalized procedure was created by the federal highway administration to design mixtures. Many researches on porous asphalt mixture have been conducted for the past two decades. However, there remains some concern about the potential adverse impacts of infiltrated surface water on the underlying groundwater. The purpose of this paper is to presents a short review on the application of porous asphalt pavement stormwater treatment. Design/methodology/approach In this paper, a critical review on history and benefits is presented followed by review of general studies of using porous asphalt pavement, and some recent scientific studies that examine potential contamination of soil and groundwater because of infiltration systems. Findings This paper indicates that porous asphalt pavement is more efficient than conventional pavements in terms of retaining pollutants, improving the quality of water and runoff while maintaining infiltration. Originality/value This paper may also help reduce land consumption by reducing the need for traditional storm-water management structures. However, on the other hand, the priority objectives which is minimizing increased flooding and pollution risks while increasing performance efficiency and enhancing local environmental quality-of-life is achieved.

Predicting Truck Load Variation Using Q-Truck Model

The study of heavy vehicle forces on pavement is important for both vehicle and pavement. Indeed it was identified several factors such as environment, materials and design consideration affects pavement damage over time with traffic loads playing a key role in deterioration. Therefore, this paper presents dynamically varying tire pavement interaction load, thus enable to assess the strain response of pavements influenced by road roughness, truck suspension system, variation of axle loading and vehicle speed. A 100m pavement with good evenness was simulated to check the sensitivity of the dynamic loads and heavy truck vertical motions to the roughness. The most important performance indicators that are required in pavement distress evaluation are radial strain at the bottom of the asphalt concrete and vertical strain at the subgrade surface was predicted using peak influence function approach. The results show that truck speed is the most important variables that interact with truck suspension system and thus effect of loading time are extremely important when calculating the critical.

Effect of Charcoal Ash Coconut Shell from Waste Material at Different Size on the Physical Properties of Bitumen

Environmental pollution caused by abundant wastes from agricultural activities has increased in recent years because of increased productivity. Agricultural waste recycling has been employed to solve this problem. Coconut shell charcoal (CSC) ash is a by-product of coconut shell (CS) used as a bitumen modifier to enhance the properties of the binder. This study investigated the effect of fineness charcoal ash from CS on the rheological properties of bitumen. Penetration, softening point, and viscosity tests were performed to determine the properties of the binder. Laboratory simulation of aging called rolling thin film oven test was applied in this study. CSC at different sizes (< 75μm, 75–150μm, and 150–300μm) was added to replace bitumen 60/70 PEN at 0%, 10%, 15%, and 20% by weight of the binder, respectively. Result showed that the bitumen became more viscous and that the softening point of bitumen increased, whereas the rate of penetration decreased when CSC was incorporated. CSC at a proper amount improved the resistance of bitumen to temperature susceptibility. In addition, the modification of bitumen can relieve the effect of aging. Modified bitumen shows better result when incorporated with the finest particle (< 75μm) of CSC compared with other sizes.

Adapting eXtreme Programming Approach in Developing Electronic Document Online System (eDoc)

eXtreme Programming (XP) is one of new discipline of software development methodology on values of simplicity, communication, feedback and also courage. XP is an explorative and agile development method that seeks to satisfy the customer through early and continuous delivery of valuable software. XP software development process starts with planning, and all iterations consist of four basic phases in its life cycle: designing, coding, testing, and listening. This paper tends to report the experience in adapting XP in developing electronic document online system for the use of Centre for Diploma Studies, Universiti Tun Hussein Onn Malaysia (eDoc). The project under study is a system that is use to store office documents such as letter in an online database. The objective of this paper is to discuss the XP practices that had been choosed and also the lesson learnt by practising XP in developing eDoc.