Possibility of production high strength lightweight concrete containing organic waste aggregate and recycled steel fibers

This study combines two types of waste materials to achieve sustainable lightweight concrete (LWC) including agricultural and industrial wastes that hold high potential to reduce global environmental pollution. A novel application of 35% treated date seed (DS) wastes as partially replaced by volume to natural coarse aggregate in producing sustainable LWC was investigated. Calcium hydroxide solution was utilized as a treatment to extract cellulose from the achieved hemicelluloses of the DS. Fourier transform infrared spectroscopy was utilized to analyze the structural characteristics of the isolated cellulosic samples before and after treatment. Then different volume fractions of steel fibers (0.5, 0.75, and 1%) recycled from scrap tires were added to the LWC with 35% DS. Several experimental tests, including slump test, compressive strength, oven-dry density, split tensile strength, flexural strength, and water penetration depth, were carried out in this investigation. The results demonstrate that concrete containing 35% DS and reinforced with 1% recycled steel fibers show enhancement in the compressive, tensile, and flexural strengths by about 15.2, 32.6, and 58.2%, respectively, and reduces the permeability by 16.1% relative to the reference concrete mixture.