Screw Pine (Pandanus odoratissimus) as an Additive on Making Concrete for Better Structural Stability

Abstract

INTRODUCTION

Concrete is one of the most widely used constructional materials. One of its properties is brittleness, which makes it poor when it comes to tensile strength. To improve its tensile strength, fibers are added to concrete, which is known as fiber-added concrete. One of the most noticeable applications of natural fibers is to replace man-made fibers as reinforcement in concrete production. Among these fibers that can be used for construction, purposes are the screw pine. The said natural fiber is extracted from the screw pine plant and is known to have excellent mechanical properties because it has been widely used for making traditional products. Additionally, the said fibers are considered to be even tougher compared to an orange. Pandan can be easily cultured in typical places. Durability is assured using pandan. Given the potential properties of screw pine that has as a natural fiber, the researcher aimed to examine the difference in the structural stability of concrete infused with screw pine and a 5-kilogram normal concrete.

METHODS

Seventy leaves of screw pine were collected and extracted by boiling and then soaking in 5% sodium hydroxide (NaOH) solution for 90 minutes. The leaves were dried under the sun for two days until it became ivory in color. The screw pine fibers were mixed along with the course, fine aggregates, and cement. It was thoroughly mixed. Six concretes were subjected to structural stability test: three screw pine-reinforced concretes and three normal concretes. The concretes were dropped from a two-foot height. The fragments of the concrete were separated and the remains were weighted and recorded. T-test was used to know which performed better between normal and screw pine-reinforced concrete.

RESULTS

After conducting the drop test, the average weight of the screw pine concretes went from 9.8 kg to 7.3556 kg, while the normal concrete became 4.8411 kg in weight. The variance of the screw pine concrete is 4.2169, which is lower than that of the normal concrete which is 12.2251. Substituting the values into the formula gave a t-value of t = 1.8603. Using the t-test tabular values, the critical value of t is 1.746, considering that the degree of freedom is 16. Since the calculated t exceeds the critical value, the null hypothesis was rejected.

DISCUSSIONS

The researcher concluded that the structural stability of the concretes with screw pine fibers was higher than that of the normal concrete since it makes the concrete stronger and enhances its resistance from breaking.