Abbas Al-Hdabi

Development of Sustainable Cold Rolled Surface Course Asphalt Mixtures Using Waste Fly Ash and Silica Fume

AbstractThe reduction of hot asphalt mixtures for the usage and development of sustainable supplementary cold asphalt mixtures (CAMs) for the construction of road and highway surface layers is a major issue for researchers around the world. This reduction will benefit environmental impact, cost effectiveness, and energy savings. Furthermore, because CAMs comprise a remarkable portion of industrial waste (the disposal of which consumes virgin lands), they are attractive to road and highway authorities. The primary aim of this investigation is to develop new cold rolled asphalt (CRA) with the same gradation as hot rolled asphalt (HRA), which is usually used as a surface course in the U.K., and to improve its mechanical properties and durability by using waste and by-product materials as mineral fillers and additives. Waste fly ash (WFA) was used as a replacement for conventional mineral filler and a by-product silica fume (SF) was used as an additive to enhance the mechanical properties and durability of CR...

Laboratory studies to investigate the properties of novel cold-rolled asphalt containing cement and waste bottom ash

Cold bitumen emulsion mixtures provide valuable advantages over hot mixture asphalt in terms of economic and environmental points of view. The total energy required for mixing, transportation and laying such mixtures is less compared with the traditional hot mixtures. These laboratory studies describe the results of a new developed cold-rolled asphalt (CRA) to be comparable with the traditional hot-rolled asphalt through the addition of waste bottom ash (WBA) to the CRA containing cement as the mineral filler. The mechanical properties were assessed by stiffness modulus and uniaxial creep tests, while water sensitivity was inspected by evaluating the stiffness modulus ratio before and after samples conditioning. The experimental results have shown a significant improvement in the mechanical properties and a substantial upgrading of material resistance to water sensitivity from the addition of WBA to the cold asphalt containing cement.

Enhancing the Mechanical Properties of Gap Graded Cold Asphalt Containing Cement Utilising By-Product Material

The little stiffness modulus, high voidage and long curing time has limited the use of CBEMs (cold bituminous emulsion mixtures) in road and highways to pavement experiencing low traffic. The aim of this study is to improve the properties of gap graded CRA (cold rolled asphalt) containing OPC (ordinary portland cement) as filler by addition of a by-product material as an activator. OPC was added to the CRA as a replacement to the conventional mineral filler (0%-100%), while LJMUA (Liverpool John Moores University Activator) was added as an additive in the range from 0%-3% by total mass of aggregate. Laboratory tests included stiffness modulus and uniaxial creep test to assess the mechanical properties. The results have shown a considerable improvement in the mechanical properties from the addition of LJMUA to the CRA containing OPC especially for the early life stiffness modulus that is the main disadvantage of the cold mixtures.

Improving Asphalt Emulsion Mixtures Properties Containing Cementitious Filler by Adding GGBS

AbstractProduction and use of sustainable cold asphalt emulsion mixtures (CAEMs) that are comparable to traditional hot mixtures and relevant for roads and highway construction might achieve severa...

Indirect Tensile Stiffness and Permanent Deformation of Microwave Treated Cold Bituminous Emulsion Mixtures (CBEMS) Containing Cementitious Activated Waste Fly Ash

The mechanical properties in terms of indirect tensile stiffness modulus (ITSM) properties and permanent deformation of CBEMs containing new cementitious materials made from activated blend of waste fly ash and inert Limestone filler were investigated. CBEMs were prepared with these fillers, and then these mixtures were subjected to microwave treatment at four treatment time and high power level. The aim was to identify the influence of microwave treatment on the mechanical properties and identify the microwave suitable application time ranges.

Improving the Mechanical Properties of Cold Rolled Asphalt Containing Cement Utilising by Product Material

Reduction of hot asphalt mixtures for the usage and development of sustainable supplementary Cold Asphalt Mixtures (CAM) for the construction of road and highway surface layers is a hot subject for researchers around the world. This will cover many advantages in terms of: environment impact, cost effectiveness and energy saving.