Analyseur de mélange d'asphalte pour les solutions technologiques de recyclage de l'asphalte des chaussées
Market background
By 2019, China’s total road length had reached 4.846,500 km et autoroutes atteints 142,600 kilomètres, ranking first in the world. At the same time of the rapid construction of domestic expressways, it has also entered a continuous large-scale maintenance period. Asphalt pavement in the maintenance and expansion of the construction of a large number of waste materials, these old materials regeneration, not only reduce environmental pollution, but also reduce material consumption, is an important means to achieve the sustainable development of highway transportation and urgent need. Through the asphalt pavement recovery material recycling technology, the old asphalt pavement asphalt mixture is dug and recovered, broken and screened, and then an appropriate amount of new aggregate and new asphalt are added, et le mélange d'asphalte recyclé est formé pour répondre aux exigences de performance, puis utilisé pour la construction de trottoirs ou de bases. Selon le processus actuel et les conditions techniques, il existe deux principales méthodes techniques pour la régénération des anciens matériaux de chaussée en asphalte: d'abord, la technologie de régénération thermique vise principalement à restaurer les performances des anciens enrobés; Deuxième, c'est une technologie de régénération à froid qui consomme beaucoup de vieux matériaux comme bouche principale.
Dans 2019, afin d'améliorer le niveau de recyclage des matériaux des chaussées km et d'assurer la qualité des projets de régénération des chaussées en asphalte, le ministère des Transports a révisé le JTG F41-2008 “Spécification technique pour la régénération des chaussées en asphalte routier” et promulgué “JTG/T 5521-2019 Spécification technique pour la régénération des chaussées en asphalte routier”.
automatic asphalt extractori is mainly used in the field of thermal regeneration.
Analyseur de mélange d'asphalte pour les solutions technologiques de recyclage de l'asphalte des chaussées
Parmi eux, there are clear quality requirements for asphalt mixture recovery material (RAP) in the regulations:
Bitumen was extracted by means of extractor and then the content of bitumen and related bitumen indexes were analyzed.
Asphalt content and asphalt performance testing of asphalt mixture recovery (RAP) shall be performed in accordance with the following requirements:
| Inspection item | Inspection frequency | Quality requirements or permissible deviations | Méthode d'essai | ||
| Highway, Classe 1 highway | Other grade highways | ||||
| RAP moisture content (%) | Once every business day | ≤3 | ≤3 | Appendix B | |
| Aggregate gross volume relative density in RAP | 1 time /5000t RAP | Actual measurement | Actual measurement | T0722, T0304, T0330 | |
| Ore gradation in RAP | 0.075mm pass rate (%) | 1 time /2000t RAP | ±3 | ±4 | T0722, T0302，T0327 |
| 0.075mm pass rate (%) Screen pass rate above 0.075mm (%) | 1 time /2000t RAP | ±8 | ±10 | ||
| RAP asphalt | Content (%) | 1 time /2000t RAP | ±0,5 | ±0.6 | T0722 or T0735 |
| 25℃ Penetration (0.1mm) | 1 time /5000t RAP | ±6 | ±8 | T0722, T0726，T0604 | |
Analyseur de mélange d'asphalte pour les solutions technologiques de recyclage de l'asphalte des chaussées
1, RAP heating and drying to constant weight, heating temperature of 60℃.
2, the current “Highway engineering asphalt and asphalt mixture test Regulations” (JTGE20)T0726 Absen method to recover asphalt from asphalt mixture recovery material (RAP). If other methods are used, repeatability and reproducibility tests and blank bitumen calibration are required.
3, measure the content of asphalt and recovered asphalt of 25℃ penetration, 60℃ viscosity, point de ramollissement, 15℃ ductility and other indicators.
4. Blank asphalt calibration must be carried out in any of the following cases: When replacing the Absen asphalt recovery equipment; When changing trichloroethylene varieties or suppliers; When the performance of recovered asphalt is abnormal; When the source of asphalt mixture recovery material (RAP) changes.
Analyseur de mélange d'asphalte pour les solutions technologiques de recyclage de l'asphalte des chaussées
5, the allowable error of the renaturation test is: needle size ≤5(0.1mm), viscosity ≤ 10% of the average, softening point ≤2.5℃; The allowable error of reproducibility test is: needle penetration ≤10(0.1mm), viscosity ≤ 15% of the average, softening point ≤5.0℃. If the allowable error range is exceeded, the recovered asphalt should be discarded, re-calibrated and recovered.
En même temps, the proportion of asphalt mixture recovery material (RAP), the amount of new asphalt label and regenerant should also refer to the recovered asphalt grade. Asphalt mixture recovery material (RAP) in asphalt mixture blending rate is low, laboratory research is mostly 30% à 40%, the solid engineering application is lower, generally 20% à 30%.