Performance analysis of palm tree microfibers in concrete

Area of Science:

• Materials Science
• Civil Engineering
• Sustainable Construction Materials

Background:

• Concrete is a vital construction material facing challenges in sustainability and energy efficiency.
• Palm Tree Fronds (PTF) offer a potential source of natural fibers for material enhancement.
• Investigating PTF as a partial sand replacement in concrete addresses waste utilization and material innovation.

Purpose of the Study:

• To evaluate the impact of chemically treated Palm Tree Fronds (PTF) microfiber as a partial sand replacement in concrete.
• To assess the effects of varying PTF content on concrete's mechanical, physical, and thermal properties.
• To determine optimal PTF incorporation levels for balancing performance in different concrete grades.

Main Methods:

• Preparation of concrete mixes (C28, C35, C40) with 0-4% PTF microfiber replacing sand.
• Testing of 571 concrete samples using destructive (compressive, tensile strength) and non-destructive (UPV, rebound hammer) methods.
• Analysis of density, water absorption, and thermal conductivity, complemented by Scanning Electron Microscopy (SEM).

Main Results:

• PTF addition significantly improved concrete workability and enhanced thermal insulation (26-33.6% reduction in thermal conductivity).
• Mechanical properties showed a decline: compressive strength reduced by 14.5-43.6% and tensile strength by 21.3-35.6%.
• Density decreased, while water absorption increased substantially (up to 51.2% at 4% PTF), indicating increased porosity.

Conclusions:

• Chemically treated PTF microfiber can enhance workability and thermal insulation in concrete, offering potential for energy-efficient construction.
• Mechanical strength reduction necessitates careful consideration of PTF content and potential use of hybrid fiber reinforcement.
• Optimal PTF content varies by concrete grade, with levels below 1% recommended for C28 and 2.3-2.5% for higher grades, particularly for semi-structural applications.