The Design Of Epoxy RAP Material And Its Application In Repairing Potholes In Asphalt Pavements

Due to the shortcomings of the traditional repair methods of asphalt pavement pits at this stage,the assembly rapid repair technology is proposed.Because of the limitation of maintenance technology,after cutting and chiseling the disease location of pit trough,the bottom surface flatness is poor,and the bottom surface of pit trough needs to be leveling.In order to save resources,protect the environment and save costs,this study will re-use the waste asphalt mixture,which collected from the process of cleaning the trench,to pave the road.There are many uncontrollable factors in the construction site.The waste asphalt mixture generated by cleaning the damaged asphalt pavement is usually dusty and moist.The early strength of the commonly used emulsified asphalt cold recycled mixture is low,and the bonding performance is poor.The maintenance time is greatly decided by the demulsification speed,and the regeneration quality is difficult to meet the requirements.To achieve the requirement of high quality and rapid repair,this paper developed a new material,WEA(Waterborne Epoxy Adhesive)binder,which can quickly bond waste asphalt mixture with dust and moisture,and studied the performance of WEA binder and leveling material made of recycled waste.In this study,the raw materials were screened according to the performance requirements of WEA binder and leveling layer materials,and the types of epoxy resin,curing agent and other auxiliary materials that constitute WEA binder were determined.Then,the optimal dosage of curing agent and the optimal dosage range of toughening agent and diluent were obtained through a separate performance test.On this basis,the orthogonal test was designed,and the optimal ratio of other components in WEA binder except accelerator was obtained through the analysis of the optimal order method.Finally,the dosage of accelerator was determined by controlling the surface drying time at different temperatures,and the basic formula of WEA binder was obtained.The test results of material properties at different storage times show that the bond strength and curing rate of the prepared WEA binder decrease significantly after 40 days of storage,and the maximum storage period of each component is determined to be 40 days.The variation of viscosity with time was obtained in the experiment,and the WEA binder could be well mixed with waste within 24 min.Based on the Shenzhen entity project,in view of the frequent occurrence of pit diseases of asphalt pavement in July during the high-temperature rainy season,the performance level of WEA cement recycling waste with dust and moisture as leveling material was explored.Two kinds of waste generated after pit treatment were collected when there was no rain in July and there was no obvious rain on the road surface after rain.The moisture content and ash content were measured to be 2%,0.42%and 5%,0.16%,respectively.According to Marshall test and splitting test,the optimal amount of glue required for the reuse of the two kinds of waste as leveling material was determined to be 10%and 12%,respectively.Through uniaxial compression test,immersion Marshall test,freeze-thaw splitting test,rutting test,and beam bending test,and compared with the same waste of emulsified asphalt cold recycling,the compressive strength,compressive resilient modulus,water stability,high temperature stability,and low temperature crack resistance of the two kinds of waste recycled by WEA cement can meet the performance requirements of the leveling material below the patch.