Automated Whole Life Road Repair and Thin Surfacing

该项目旨在研究、生产和展示用于生产“无故障”坑洞修补的新型预热设备。为此，我们采用可再生能源，取代目前使用的有害和污染的石油气。虽然已研究替代冷修补材料，但热铺沥青仍然是道路磨耗层的首选。然而，目前用于修补例如坑洞的设备和方法本质上是不可靠的，经常以早期故障为特征。同样，薄沥青覆盖层也需要确保使用寿命长并节省成本，从而大幅减少路面维护过程中的二氧化碳排放量。项目团队经过八年的调查，包括坑洞维修的加速寿命测试，证明目前的设备和方法不可靠，因为它们不符合材料系统中热能传递的基本原理。如果没有这一点，就不可能将新涂的沥青可预测地融合到现有的混凝土或沥青基层上，从而提供与周围道路的剩余寿命相当的维修寿命。对于可预测的熔融，在坑穴填充后的压实过程中，主体-填充边界区域的温度必须超过所谓的沥青停止温度（85摄氏度）。目前使用液化石油气火焰加热的未经计算的预热可能会提供不足的温度或有损坏沥青粘合剂的风险。使用我们内部开发的基于传热科学的数值模型，我们发现通常发生的气候条件组合，内部热耗散和穿过主体-填充边界的不完全热传递可导致温度显著降低甚至当沥青在高温（例如160 ℃）下引入时，边界区域中的温度（例如50 ℃）也比停止温度高。我们内部开发的独特的3D打印多热电偶传感器可以同时测量高于和低于该边界的温度，这使我们能够证明这一点。

This project aims to research, produce and demonstrate novel pre-heating equipment for producing 'no-failure' pothole repairs. We adopt renewable power for this, displacing current use of hazardous and polluting LPG.Whilst alternative cold repair materials have been investigated, hot placed asphalt remains the preferred option for road wearing course. However, current equipment and methods used in repairing eg potholes are inherently unreliable, frequently characterized by early failure. There is a similar need to ensure long life and cost savings with thin asphalt overlays that promise to drastically reduce the CO2e footprint of road pavement upkeep.Eight years of investigation by the project team, including accelerated life testing of pothole repairs, proves that current equipment and methods are unreliable because they do not operate according to the fundamental principles of thermal energy transfer in material systems. Without this, it is not possible to predictably fuse newly applied asphalt to existing concrete or asphalt base and thus deliver repair life comparable to the residual life of the surrounding road. For predictable fusion, temperatures in the host-fill boundary region must exceed the so-called cessation temperature of asphalt (85 deg C) during the compaction process following pothole filling. Current uncalculated pre-heating using LPG flame heating may provide insufficient temperatures or risk damaging the bitumen binder.Using our in-house developed numerical models, founded on heat transfer science, we have discovered that commonly occurring combinations of climatic conditions, internal heat dissipation and imperfect heat transfer across the host-fill boundary can result in temperatures substantially lower (eg 50 deg C) than cessation temperature in the boundary region even when asphalt is introduced at high temperature (eg 160 deg C). Our in-house developed, unique, 3D printed, multi-thermocouple sensor, which simultaneous measures temperatures above and below this boundary has enabled us to prove this.