Lukman Salami

Rutting, which is permanent deformation or consolidation of asphalt pavement, is one of the flexible pavement failures. Research has shown that one of the ways of resisting this failure is by modifying the rheological properties of bitumen. This modification can be achieved by the addition of dissolved plastic water sachet (DPWS), a well-known waste in Nigeria, to bitumen. This study was conducted to investigate the effect of DPWS on the rheological properties of bitumen and at the same time reduce the environmental hazard associated with PWS disposal with consequential pavement material improvement. Bituminous blends containing DPWS at various percentages 0, 1, 3, 5, 7, 9, 11, 13, 15 and 17% by weight of conventional bitumen were used for the study. Tests on rheological properties such as dynamic viscosity, phase angle, peak shear stress and peak shear strain were carried out on unmodified and DPWS modified hot and warm bitumen blends to determine the corresponding complex shear mo...

Shear strength is one of the most important soil properties in almost all geotechnical engineering problems. Therefore, this study was aimed at investigating the effect of gravel on the shear strength of clayey soil. Two clayey soil samples were obtained from a dug pit from different locations in Osogbo, Osun State and the gravels were collected locally. Three different gradations of gravel (2-6mm, 6-12mm, and 12-20 mm) were mixed in a dry state in percentages of 5, 10, 15, 20, 30, 40 and 50% with the collected clay soil respectively. Initially, some physical properties of clayey soil and the gravel, which include specific gravity, particle size analysis, liquid limit and plastic limit, were determined in accordance with BS 1377-3:2018. Consequently, the California Bearing Ratio (CBR) and Consolidated - Undrained (CU) triaxial compression tests at three different confining pressures of 50, 100 and 150 kN/m2, with a loading rate of 0.5 mm/min were carried out on the clay-gravel mixtu...

This study was carried out to investigate the performance of Hot and Warm mix asphalt (HMA and WMA) with dissolved plastic bottle (DPB) modified bitumen. In this study, 1 17% @ 2% DPB by weight of bitumen was blended with 60/70 straight-run bitumen to produce hot and warm (+3% Sasobit) DPB modified bitumen blends. The produced binders were subjected to ductility, penetration, softening point, viscosity, flash and fire point and specific gravity tests to understand the effect of this modification. Also, the binders were used in preparing HMA and WMA concrete respectively. Marshall Properties (stability, flow, stiffness, volume of void, void filled with bitumen and bulk specific gravity) were evaluated on HMA and WMA concrete produced. Results revealed that addition of polyethylene terephthalate (PET), in dissolved form (0 – 17%), increased the softening, viscosity, specific gravity, flash and fire points of both hot and warm modified bitumen blends but decreased their penetration and...