# Influence of UHMWPE on the expansion characteristics of expansive soil: Experimental studies

## TL;DR

This study shows how adding UHMWPE fibers to expansive soil can reduce its swelling, with optimal results at 0.3% fiber content and 9 mm length.

## Contribution

The paper introduces UHMWPE fibers as a novel material for controlling expansive soil behavior and quantifies their effectiveness.

## Key findings

- Swelling pressure and free swelling ratio decrease significantly with UHMWPE content and length up to thresholds.
- Optimal UHMWPE content is 0.3% and length is 9 mm for maximum soil improvement.
- Swelling pressure and fiber content have a quadratic relationship, while fiber length has a linear or power function relationship.

## Abstract

This paper investigates the effectiveness of using Ultra-High-Molecular-Weight Polyethylene (UHMWPE) Fiber to improve expansive soil. The test results indicate that the amount and length of UHMWPE significantly affect the swelling pressure and free swelling ratio of the reinforced soil. The swelling pressure of reinforced expansive soil exhibits a significant negative correlation with both the UHMWPE content (p < 0.05) and its length. The free swelling ratio of reinforced expansive soil was significantly negatively correlated with both the content (p < 0.05) and length of UHMWPE. When the UHMWPE content exceeds 0.3% the weight of the soil, there is no significant decrease in the swelling pressure of the reinforced soil (p = 0.052, close to the threshold of significance). When the length of UHMWPE is greater than 9 mm, there is no significant decrease in the free swelling ratio of the reinforced soil (p = 0.165). Thus, it is recommended to use 0.3% UHMWPE with a length of 9 mm for optimal results. Swelling pressure, free swelling ratio and fiber content follow a quadratic polynomial relationship. While, the relationship between swelling pressure and fiber length is linear. The relationship between free swelling ratio and fiber length is a power function.