Sustainable Asphalt-Rubber Technology: Evaluating Insoluble Rubber Powder and Its Impact on Binder Content Correction

Description

Sustainable Asphalt-Rubber Technology: Evaluating Insoluble Rubber Powder and Its Impact on Binder Content Correction

Edson Olivir Zotto Andrade
Daniel Anijar de Matos
Asfalto BR – Treinamentos e Serviços.
Recife, Pernambuco, Brazil
Universidade Federal do Mato Grosso do Sul, (UFMS),
Campo Grande, Mato Grosso do Sul, Brazil
edson@asfaltobr.com
daniel.matos@ufms.br

ABSTRACT. This study evaluates the presence of insoluble rubber powder in asphalt and its impact on correcting the asphalt binder content in hot-mix asphalt using Asphalt-Rubber technology. The investigation included a comprehensive approach involving the physical and chemical characterization of four different samples of rubber powder and the resulting asphalt matrix. The study also analyzed rubber dispersion in asphalt through agitation (wet process) and quantification of insoluble material retained in extraction equipment filters, focusing on the efficiency of rubber powder incorporation.
To understand the production process of rubber powder dispersion in the asphalt binder, samples were collected after 2 hours of agitation and an additional 2 hours of digestion. They subjected the materials to Soxhlet extraction tests, determining the percentage of insoluble material in the system. During this analysis, changes in the behavior of the modified asphalt were observed. These changes included an increase in the softening point, a reduction in the recovered penetration percentage, and an improvement in the binder’s elastic recovery capacity as the rubber powder was solubilized in the asphalt.
After 4 hours of dispersion and digestion, researchers carried out additional tests to evaluate the storage stability and viscosity of the modified binder. They subjected the binder soluble in trichloroethylene, extracted using the Soxhlet method, to simple distillation and Abson recovery tests, revealing detailed information about its composition after the dispersion process. The team characterized the residual asphalt through physical tests, including penetration, softening point, and elastic recovery, which provided essential data on changes in binder properties over time.
Additionally, thermogravimetric analyses of the asphalt-rubber were performed, and the results were compared with those obtained for the original asphalt matrix. These analyses enabled a detailed assessment of the thermal stability of the modified material and the interaction between the rubber powder and the asphalt binder.

This quantitative and experimental approach allowed researchers to precisely measure the solubility of Asphalt-Rubber in trichloroethylene, providing valuable insights into the interaction between rubber powder and asphalt binder in conventional mixtures and mixtures containing reclaimed asphalt pavement (ongoing research). Applying these findings can guide the formulation of more efficient and innovative asphalt mixtures, contributing to developing more sustainable, durable, and high-performance asphalt materials for road infrastructure applications. This work emphasizes the importance of using sustainable technologies, such as Asphalt-Rubber, in road construction to enhance durability and reduce environmental impact.

KEYWORDS: Asphalt-rubber, dispersion, digestion, distillation, sustainability, durability, environmental.