Automated Whole Life Road Repair and Thin Surfacing

该项目旨在研究、生产和演示新型预热设备，以实现“无故障”坑洞修复。为此，我们采用可再生能源，取代目前使用的危险和污染的液化石油气。虽然替代冷修复材料已被研究，热放置沥青仍然是道路磨损过程的首选。然而，目前用于修复eg凹坑的设备和方法本质上是不可靠的，经常出现早期故障。同样需要确保长寿命和节省成本的薄沥青覆盖层有望大幅减少道路路面维护的二氧化碳排放量。项目团队进行了八年的调查，包括凹坑修复的加速寿命测试，证明目前的设备和方法是不可靠的，因为它们不按照材料系统中热能传递的基本原理运行。如果没有这一点，就不可能预测地将新应用的沥青融合到现有的混凝土或沥青基础上，从而提供与周围道路的剩余寿命相当的修复寿命。为了实现可预测的融合，在坑洞填充后的压实过程中，主-填料边界区域的温度必须超过所谓的沥青停止温度（85℃）。目前未计算的使用LPG火焰加热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，即使在高温（例如160℃）下引入沥青，通常发生的气候条件、内部散热和跨越宿主-填充边界的不完美传热的组合也会导致温度大大低于边界区域的停止温度（例如50℃）。我们内部开发的独特的3D打印多热电偶传感器，可以同时测量该边界上下的温度，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.