The present experimental study addresses the proper disposal of agricultural residues, such as bamboo sawdust, coconut fibers, and acai fibers. Improper disposal of these materials leads to irresponsible environmental waste. To tackle this issue, the research line on new geotechnical materials proposes the use of these residues as soil reinforcement. The study investigates the interaction of these vegetative reinforcements with tropical soil over time, taking into consideration degradation processes resulting from environmental factors. Additionally, it examines the properties of these vegetative residues and how they influence the mechanical and durability characteristics of the composites. It also proposes a correlation by analyzing the Key Parameter curves that translate the interaction between composite properties and simple compression strength.

The results show that initially, composites reinforced with bamboo sawdust exhibited a pronounced peak in strength, surpassing coconut fibers and acai fibers. However, their strength rapidly decreased after the peak, unlike coconut and acai fibers, which maintained high values. In terms of maximum strength and post-peak strength, acai fiber outperformed coconut fiber. During the 6-month exposure to weather conditions, all reinforcement materials showed a loss of strength, but coconut fibers and acai fibers continued to contribute as reinforcement elements in the tropical soil matrix, as their simple compression strength remained higher compared to unreinforced tropical soil. Over the months, coconut fibers exhibited a considerably lower reduction in strength compared to the other materials, demonstrating their resistance to degradation.

Although vegetative materials have disadvantages such as variations in mechanical properties and susceptibility to degradation, their use is feasible in situations where immediate stabilization of the construction is required. This study contributes to understanding the behavior of these composites, highlighting the potential for reusing vegetative waste in geotechnical engineering as a sustainable alternative.