Effectiveness of areca fiber and cement on the engineering characteristics of compressed stabilized earth blocks

Abstract

This study investigates the potential of integrating areca fiber as a reinforcement agent in Compressed Stabilized Earth Blocks (CSEBs), used in combination with cement. Traditional earth-based construction methods, once prevalent, have seen a decline in industrialized nations with the advent of modern building materials. However, there is a growing resurgence in the use of earth-based materials, motivated by their economic, social, and environmental sustainability benefits. This renewed interest in CSEBs is primarily due to their superior energy efficiency and lower greenhouse gas emissions, especially when compared to conventional materials like fired clay bricks or concrete blocks. Areca catechu, widely recognized as the areca palm, thrives in the tropical regions of the Pacific, Asia, and East Africa. The fibers derived from areca nutshells, often regarded as agricultural waste, present an intriguing material for study. While the application of areca fiber in soil reinforcement has been previously acknowledged in scholarly literature, its specific role in enhancing the engineering properties of CSEBs represents a novel area of exploration, which this research aims to address comprehensively. In this research endeavor, CSEBs were manufactured with varying proportions of areca fibers, spanning from 0 % to 3 %, based on the dry mass of soil. Subsequently, these blocks underwent comprehensive testing to assess their strength and durability characteristics. Strength properties were evaluated through unconfined compression, split tensile strength, and flexural strength tests, while durability was meticulously examined using wet strength, water absorption, submersion, and efflorescence tests. Here, CSEBs displayed increases in compressive strength (107.04–436.38 %), split tensile strength (208.66–358.08 %), and flexural strength (16.49–82.47 %). Durability tests revealed enhanced wet compressive strength (up to 100.42 % increase) and optimized water absorption rates. A notable finding is identifying 2 % areca fiber content as optimal, yielding significant improvements in strength and durability parameters. Microstructural analysis using Scanning Electron Microscopy (SEM) further confirmed the benefits of 2 % fiber content, showing a compact and cohesive internal structure with reduced voids and fissures. This microstructural integrity underlines the enhanced bonding and stability imparted by the areca fibers. Another essential aspect of the study was evaluating the compliance of CSEBs with various international standards on earthen construction. The fiber-reinforced blocks met or exceeded several standards, demonstrating their suitability for broader construction applications. Finally, this study underscores the promise of areca fiber as a valuable reinforcement material in CSEBs stabilized with cement. This innovative approach offers a sustainable and eco-friendly building material option, aligning with the growing emphasis on environmentally conscious construction practices.