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Nano materials are being used in concrete technology to enhance performance grade sustainably of construction field works like rigid highway pavement. Nano materials like Nano Al2O3 are used as admixture for the cementitious materials to improve the mechanical and durability properties related to the physio-chemical reactions. The overall objective of this research is to evaluate the effects of Nano Al2O3 addition on the abrasion durability response of concrete pavement. These investigations are conducted to study different Nano Al2O3 contents (0.5, 1, 1.5, 2%) by weight of cement on the concrete strength and abrasion resistance by using the manufactured calibrated rotary cutter device for evaluation process and microstructure analysis by Scanning Electronic Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) tests. The compressive strength was tested at 28 days of curing and the results showed that the compressive strength of concrete increases up to 36% at 28 days by addition of 1% nano-alumina as a replacement of cement; Optimal content (1% by weight of cement) is found that appears better abrasion, durability abrasion performance and at the same time, achieves the main requirement of concrete highway pavement (strength and workability).

Nano materials are being used in concrete technology to enhance the sustainability of performance grade for the pavement construction. In this paper, test investigations are conducted to study the addition effect of nanoparticles combination (Al2O3, SiO2) with the average diameter of 20 nm and with different acceptable percentages (Al2O3 : 0% and SiO2 : 0 %), (Al2O3 : 0.5% and SiO2 : 0.5 %), (Al2O3 : 0.5% and SiO2 : 1 %), (Al2O3 : 0.5% and SiO2 : 1.5 %), (Al2O3 : 1% and SiO2 : 0.5 %), (Al2O3 : 1.5% and SiO2 : 0.5 %) and (Al2O3 : 1% and SiO2 : 1 %) by weight of cement on the mechanical properties (compressive strength, flexural strength and modulus of elasticity) and the thickness design of concrete pavement. The optimal combination which contributed to the highest values of mechanical properties at (28) days in order to maintain the workability requirement of nano concrete mixes was found (Al2O3 : 1% and SiO2 : 0.5 %) which associated with the decrement in concrete pavement thickness, when all other factors were held constant. It is concluded that cement modification with nano particles (combination of SiO2 and Al2O3) increased compressive strength, flexural strength and modulus of elasticity though decreased concrete pavement thickness.

High performance concrete pavement appears to be the best choice for layer with high strength and low cost. In this paper, the mechanical properties were investigated which considered essential for design and requirements of rigid highway pavement. These properties were examined by compressive strength, flexural strength and modulus of elasticity. Previous test investigations were imposed for concrete mixes with different Nano SiO2 (size of 30 nm) percentage (0, 0.5, 1,1.5, & 2) % by wright of cement as mineral admixture. Also, X- Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) tests were conducted to indicate the chemical composition of the used admixture. Energy Dispersive Spectroscopy (EDS) was conducted to visualize the micro structural behaviour of concrete during hydration process. Wet and dry mixing methods were utilised to prepare the modified concrete mixes and the results of the more effective method, were adopted. Scanning electron microscopy (SEM) was utilized to investigate the microstructure and morphology of nano concrete mixes. The results of SEM indicated that the microstructural distribution of C-S-H gel were comparable for all the nano mixes. The decrease in thickness of nano concrete layer was associated with the increment in the percentage of nano silica add to the mixes when the other factors remain the same. The best percentage of nano silica was 1.5% by weight of cementitious materials (by using dry mixing method). This percentage satisfied all requirements of fresh and hardened concrete mixes for highway pavement and achieved well microstructure with significant decrement in the thickness of concrete layer which positively reflected on construction cost.

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