A Comparative Study of Plant Leaf Ash as The Replacement for Fly Ash in Breeze Blocks

Abstract

Breeze blocks, or ventilation blocks, are made of concrete and fly ash produced from pulverised coal combustion in the power plant. However, the components of cenospheres found in fly ash can pose environmental and health hazards due to the methods used in their production and disposal. The growing recognition of environmental issues has led to a significant focus on repurposing industrial byproducts from plant fibers. These materials offer cost-effective, recyclable, biodegradable, and eco-friendly alternatives for fly ash, helping to reduce agricultural waste and lower the carbon footprint of construction projects. This study was conducted to investigate the compressive strength, water absorption, fire resistance, and workability of concrete mixes between the conventional fly ash breeze block and those reinforced with ashes from nipa palm leaf, pandan leaf, and corn leaf. The plant leaves were first burned into ashes and then sieved to a particle size range of 0.25 mm to 0.30 mm. Following that, the breeze block samples reinforced with various ashes were prepared according to the designated compositions. The fire resistance test (ASTM E119), water absorption test (ASTM C140), slump test (ASTM C143), and compressive test (ASTM C109) were conducted accordingly. Experimental results showed that the samples of nipa palm leaf ash had the best resistance to fire with 293.33s of burning time, the highest water resistance at 0.04% of water uptake after 24 hours, and excellent compressive strength at 5.97 MPa as compared to conventional fly ash breeze blocks and other samples. Nonetheless, the corn leaf ash showed the best slump head at 23.50 cm compared to the rest. Therefore, it can be concluded that the nipa leaf ash is a potential eco-friendly replacement for fly ash in the conventional breeze block industry.