Evaluation of High-Temperature Performance of Hungarian Bituminous Binders Using the BTSV Method

Area of Science:

• Materials Science
• Civil Engineering
• Rheology

Background:

• Traditional European bitumen classification methods (penetration, Ring and Ball) are inadequate for modern modified binders.
• The German Bitumen Typisierungs Schnell Verfahren (BTSV) offers a rheology-based alternative for high-temperature performance characterization.
• New German specifications effective 2025 will incorporate performance requirements for binders.

Purpose of the Study:

• To evaluate the high-temperature performance of commonly used Hungarian bituminous binders using the BTSV method.
• To compare BTSV results with traditional empirical parameters and German classification systems.
• To analyze the relationship between rubber content and rheological properties in modified bitumens.

Main Methods:

• Utilized the Bitumen Typisierungs Schnell Verfahren (BTSV) method to determine softening temperature (T_BTSV) and phase angle (δ_BTSV) for 137 Hungarian bitumen samples.
• Tested paving-grade, SBS-modified, and chemically stabilized rubber-modified binders.
• Determined recoverable, insoluble rubber content using Soxhlet extraction for rubber-modified bitumens.

Main Results:

• A clear trend was observed: increasing rubber content led to higher T_BTSV values and lower δ_BTSV values.
• A strong linear relationship (R² = 0.99) was identified between T_BTSV and δ_BTSV in the T_BTSV-δ_BTSV diagram.
• The BTSV method provided valuable insights into the high-temperature performance of diverse Hungarian bitumen types.

Conclusions:

• The BTSV method is a viable tool for characterizing the high-temperature performance of Hungarian bituminous binders.
• The study confirms the influence of rubber modification on bitumen rheological properties, as indicated by T_BTSV and δ_BTSV.
• Findings support the potential adoption of rheology-based methods for future bitumen specifications.