Mohd Rosli Hainin

Laboratory Performance of Crumb Rubber Concrete Block Pavement

The aim of this study was to investigate laboratory performance of crumb rubber concrete block pavement (CBP). Four different paving blocks containing 0 (control), 10, 20 and 30% rubber by total sand volume with compressive strength ranging between 23 and 64 MPa were used. The test pavement was subjected to 10,000 cycles of load repetition under a single truck wheel via a tyre inflated to 600 kPa. Nine measurements of pavement deformation and joint width were made at various stages of trafficking. Additional tests, including pull-out, skid resistances and falling weight test, were then carried out. Overall, crumb rubber CBP is observed to show inferior performance than the conventional CBP in rut, deformation, skid resistance and shear resistance but showed a great improvement in toughness. Thus, all paving blocks studied in this project have a great potential to be used according to traffic volume and types of applications.

Properties of crumb rubber concrete paving blocks with sbr latex

ABSTRACT The objective of this research is to investigate the potential of using crumb rubber as a partial substitute for coarse sand in the production of concrete paving block (CPB). Laboratory trials were conducted to investigate the effect of crumb rubber particle size. A comparison was also made between CPB mixtures containing various percentages of crumb rubber to determine the optimum crumb rubber content and water-cement (w/c) ratio. Styrene-butadiene rubber (SBR) latex was added to the mixtures of crumb rubber CPB and mechanical properties were evaluated. A total of 276 CPB were fabricated and tested in laboratory to determine the density, skid resistance and the compressive strength. The design strength level ranging from 31 to 43 MPa was achieved using w/c ratios of 0.45 to 0.55. The test results indicated that there was a systematic reduction in the strength with the increase in rubber content. Scanning electron micrograph showed that inclusion of SBR latex into the matrix did not improve the mechanical properties of the CPB. Results also revealed that a w/c ratio of as high as 0.55 without any SBR latex at 15% rubber content by total sand volume might be practically used to produce crumb rubber CPB which achieve the target compressive strength of 30 MPa.

Steel Slag as an Aggregate Replacement in Malaysian Hot Mix Asphalt

As natural aggregate sources are becoming depleted due to high demand in road construction and the amount of disposed waste material keeps increasing, researchers are exploring the use of alternative materials which could preserve natural sources and save the environment. In this study, steel slag was used as an aggregate replacement in conventional dense graded asphalt mixes (ACW14 and ACB28). Steel slag was selected due to its characteristics, which are almost similar to conventional aggregates, and the fact that it is easily obtainable as a by-product of the steel industry. The same gradations of mixtures were produced using normal crushed aggregate as control samples. The Marshall mix design system was used for sample preparation in accordance with Malaysian specifications. Samples of asphaltic concrete were subjected to the resilient modulus test, creep test and rutting test. Samples made from steel slag show significantly better results than conventional aggregate. Therefore, utilization of steel slag will reduce land fill, save natural resources and improve the strength of pavement to sustain a higher volume of vehicles. This will shift the gear in sustainable pavement construction, which is most desirable in today’s energy deficient world.

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.

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.

Potentials of steel slag and copper mine tailings as construction materials

Abstract The present rate of utilisation of mine waste in a country like Malaysia is rather below expectation compared with some advanced countries. Many studies concentrate on a better way to increase the usage of industrial byproducts in order to ease disposal problems. Enormous quantities of steel slag and copper mine tailings are deposited in yards, polluting the environment. Researchers need to pay attention to the effective use of industrial byproducts in construction to address economic and environmental concerns. The potential uses of copper mine tailings and steel slag need to be explored and the negative impact of mine tailings should be reduced by exploring potential uses of these waste materials in the construction industry. Although copper tailings have negative effects on the environment owing to their acidic content, they also have some great economic value in terms of valuable metal contents. The engineering properties of steel slag and copper mine tailings were reviewed and their various areas of application are highlighted.

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.

Performance of Waste Cooking Oil in Asphalt Binder Modification

Oxidation, hydrolysis and polymerization process during frying activity has caused the alteration value of the waste cooking oil (WCO) properties which is acid value and water content. This parameter is recognized as the quality measurement of waste cooking oil that might be affecting the performance of WCO in binder modification. Therefore, the aim of this paper is to relate the quality of WCO by the determination of the WCO parameter with the performance of WCO in modified binder by physical and rheological binder testing. Based on the finding, the high and good quality of WCO is recorded in December sample with the lowest acid value (1.66 mL/g) and water content (0.01 ml). The high quality of WCO affected the good performance of rheological properties where the higher rutting resistance and temperature failure at 64 °C is achieved by the modified asphalt binder with the addition of WCO in December sample.

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.

Comparative evaluation of hot-mix asphalt design methods

This study was done to evaluate superior performing asphalt pavements (Superpave) mixture design using local materials in Malaysia. Comparison was also done with the conventional Marshall method-designed mixture conforming to the specifications of the Malaysia Public Works Department (PWD). The experimental plan consisted of a matrix involving one granite aggregate source, two different aggregate gradation and two different asphalt binder types. Local granite aggregates being produced presently were found to conform to the consensus and source aggregate properties criteria of the Superpave mixture design system. Mixture volumetric properties showed that Superpave-designed mixture uses less asphalt binder than the PWD Marshall mixture. Rutting and moisture susceptibility tests showed that Superpave-designed mixtures are more resistant to rutting and moisture damage compared with the PWD mixture. Mixture characterisation tests showed that Superpave mixtures have higher stiffness than the PWD mixture. These indicate that Superpave-designed mixtures are superior to the PWD Marshall-designed mixture.