2-5m/min heating speed hot in place recycling equipment with ≤195 heated road surface
The construction process and quality control for hot in-place asphalt recycler
1. Construction process
Multi-step asphalt pavement hot-in-place recycler train, independently developed by Wuxi Xitong Chuangfei Highway Equipment Co., Ltd, consists of two heaters, one miller for original road pavement, one channel heater, one channel miller, one two-layer heater and one lifting remixer, total 7 separate equipments, matched with a paver, various rollers and several dumpers to operate the hot in-place work.
. Construction preparation
(1). Clean the original road pavement of road sections intended for treatment, ensuring the clean surface and free of sundries. Patch the damaged parts like existing pot holes and erosion points of the original road pavement.
(2). Determine the heating power and travelling speed of each unit of recycling train based on the old road mixture type and on-site weather condition. Normal travelling speed of the recycler train should be controlled within 25m/min.
(3). Calibrate the additive spraying device.
(4). Design new formula based on conclusion from lab, mix the new asphalt mixture and transport to the construction site.
. Original pavement heating(first layer heating)
Use two heaters for heating, speed controlled within 25m/min. After first heater heating, the road surface temp. is controlled at about 130,the second heater heating the road surface temperature is controlled at about 160-180,which can quickly soften the old pavement at a range of 2-3cm in a low temperature road surface condition.
Quality inspection standard during construction process of old pavement maintenance
| Check Content | Inspection frequency | Requirement for quality or allowable deviation | Standard | |
| Visual testing | At any moment | Surface leveling &compaction, no distinct wheel trail |
JTGF40-2004, JTGF41-2008
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| Seam | At any moment | Compact, level, straight | ||
| Construction temperature | Once for every 100m | Conform to requirements of Table 1 | ||
| Gradation of reclaimed mixture(deviation to the designed gradation) | A group every day | ≤0.075mm ±2% | ||
| ≤2.36mm ±5% | ||||
| ≥4.75mm ±6% | ||||
| The content of recycled asphalt | A group every day | ±0.3% | ||
| Regenerant adulteration rate | A group every day | ±5% | ||
| New material adding amount | A group per unit | On-the-spot survey | ||
| Marshall test | Stability(kN) | A group every day | >8 | |
| Flow value(0.1mm) | 2050 | |||
| Void ratio() | 34.5 | |||
| Degree of compaction | Every 200m/lane |
Marshall indoor density:≥98% Maximum theoretic density:94~97% |
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| Thickness | Every 200m/lane | -5mm | ||
| Width | Every 50 linear meter | ≥ the designed width, Neat edge line, comfortable | ||
| Flatness | Continual monitoring for each lane | ≤1.2mm | ||
| Water permeability coefficient | One place every 200m/lane | ≤200ml | ||
| Frictional coefficient | One place/200m | Not less than 45BPN | ||
| Texture depth | Not less than 0.55mm | |||
