Tecnico accelerated ageing (TEAGE) - a new laboratory approach for bituminous mixture ageing simulation

摘要

The available methods for accelerated ageing simulation in laboratory of compacted bituminous mixtures are often not representative of the ageing mechanisms experienced in the field. The objective of this study was to develop an alternative ageing method, Tecnico accelerated ageing (TEAGE). The method is intended to simulate the ageing of bituminous mixtures under specific environmental conditions by applying watering/drying cycles and ultra-violet (UV) radiation in equivalent levels to those observed in the field during a certain time. In this study a type of mixture was aged using TEAGE and LTOA (long-term oven ageing) methods and then tested for mechanical performance conducting stiffness, fatigue resistance and indirect tensile strength tests. Additionally, the chemical composition of the water used for the watering/drying cycles was analysed and recovered binders were tested for softening point and penetration. TEAGE-aged specimens showed clear evidence of an ageing gradient through the specimens' depth, substantial reduction in fatigue life (15% reduction in ;(6)) and a visible effect on the colouration of the UV exposed surface when compared with LTOA-aged specimens. The overall results and comparison with other studies indicate that TEAGE framework addressed in a more consistent way the ageing mechanisms that could be seen in the field.