Physical And Mechanical Properties Of Pineapple Leaf Fiber Textile Reinforced Geopolymer Mortar/ Raymart R. Balangue, Kenneth B. Bautista, Dominic B. Buduan, Niel Joshua B. Data, Alessander Vill C. Mondero and Cayle P. Olaguer.--

Bachelor's thesis

College of Engineering.-- Bachelor of Science in Civil Engineering: Technological University Of The Philippines, Manila. 2024

Includes bibliographic references and index.

The construction industry faces growing challenges in reducing its environmental
impact while meeting the increasing demand for sustainable materials. This study
investigates the physical and mechanical properties of geopolymer mortar reinforced with
Pineapple Leaf Fiber (PALF) as a renewable composite material. The geopolymer cement
used was synthesized by combining silicate and aluminate solutions with Class F fly ash

(FA). The mixture design maintained an FA-to-alkaline activator ratio of 2.5 and an NaOH-
to-Na2SiO3 ratio within the range of 0.25–0.35. PALF was treated with a 6% NaOH solution

and oven-dried for 24 hours, following the adaptation from Zin et al. (2018). The treated
fibers were incorporated into the geopolymer mortar at varying lengths (5 mm, 10 mm, and
15 mm) and volume replacements (0.25%, 0.5%, 0.75%, and 1.0%). Testing adhered to
ASTM standards to evaluate the mortar's physical and mechanical properties.

The results demonstrated that PALF treatment increased fiber density and tensile
strength (1.585 g/cm3 and 1225.58 MPa, respectively) while enhancing water absorption
(555%). Incorporating PALF reduced workability, with Mix M1 achieving the highest flow
percentage (53%) and Mix M2 showing a 22.6% reduction compared to the control. Higher
PALF volumes decreased workability and density while increasing porosity, highlighting
the need for mix adjustments such as superplasticizers or changes in liquid-to-solid ratios
for practical applications.

In relation to physical properties, Mix M2 recorded the highest density (0.47%
decrease) and water absorption (9.55% increase) compared to the control. Mechanical tests

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showed that incorporating PALF at 0.25% volume replacement significantly improved
compressive, flexural, and split tensile strengths. Mix M2 achieved the best compressive
and flexural strength results, with increases of 6.84% and 10.04%, respectively. Mix M6
demonstrated balanced performance, with compressive strength increasing by 2.74%,
flexural strength by 24.45%, and split tensile strength by 5.66%, while maintaining
acceptable density and water absorption levels. Two-Way ANOVA confirmed that PALF
volume significantly influenced the mortar’s physical and mechanical properties, while
fiber length had no significant impact.

In conclusion, this study underscores the potential of PALF-reinforced geopolymer
cement as a sustainable construction material. The best-performing mixes, M2 and M6,
demonstrated improved mechanical properties while maintaining the physical integrity of
the mortar, offering viable solutions for environmentally friendly building applications.

Keywords: Pineapple Leaf Fiber (PALF), geopolymer mortar, fly ash, alkaline treatment,
sustainable materials