Impact of Nanoscale Polyaniline and Fly Ash on Engineering Properties of Adobe Bricks for North Coast Region of Egypt

Abstract

This paper describes an experimental investigation on productbased research in the development of geopolymer-stabilized adobe composites (GSAC) using natural soil (NS), fly ash (FA), and Nanoscale polyaniline polymer (PA). An alkaline medium (AM) consisting of a sodium hydroxide and sodium silicate solution was utilized. The molarity of the sodium hydroxide solution was fixed at 14 M. The ratio of sodium silicate solution to sodium hydroxide solution was fixed at 1.5. Four mixes of GSAC were formulated: the control mixture (NS & Water; T1), (NS & AM; T2), (NS, FA &AM; T3), and (NS, FA, PA & AM; T4). An extensive investigation was conducted to examine the compressive strength, physical properties, and durability of GSAC. In addition, the experimental results were confirmed at a micro-level through microstructure analysis using scanning electron microscopy (SEM). Significant effects on all the studied characters were reported. According to the results, the composites formed by PA/FA/NS geopolymer matrix showed a superior yield in the compression and density tests, with the highest value of 7.8 N/mm2 and 2.28 g/cm3, respectively, for compressive strength and density. In the water absorption test, the compounds containing the PA/FA/NS geopolymer matrix showed the lowest yield value, measuring2.02 % and 3.11% after 2 and 24 hr of soaking in water, respectively. The results of the microstructural analysis showed the best interaction between FA and NS particles with the lowest porosity, when PA was added to the matrix.