PG Binder grades are used to classify asphalt binders based on performance at high and low temperatures.

• A. True
• B. False
• C. Not used in practice
• D. Only for pilot tests

Answer: (A)

Performance Grade ratings classify asphalt binders by how they perform at extreme temperatures, using a high-temperature portion and a low-temperature portion. A binder’s PG grade is written as PG high-low, such as PG 64-22, meaning it’s expected to resist rutting at temperatures up to 64°C and resist thermal cracking down to -22°C. This two-temperature approach shows why the statement is correct: PG grades are defined by performance at both hot and cold conditions. In practice, the high-temperature requirement gauges rutting resistance in hot weather, while the low-temperature requirement gauges cracking resistance in cold weather. This system is widely used in the field and design work, not limited to pilot tests or theoretical concepts.