Research On The Application Of Full Depth Foam Asphalt Cold Recycling Pavement In National And Provincial Trunk Highways

Since the reform and opening up,China’s economic development model has changed,and the economy has achieved rapid growth.Along with economic growth,the number of cars owned has also been increasing,and the degree of road damage has also increased.Traditional asphalt pavement maintenance methods mostly involve milling the old pavement and paving a new asphalt pavement after the milling is completed.In order to respond to the national "double carbon" strategy and realize the on-site recycling of waste asphalt pavement materials,this paper studies the application conditions,material composition design,compaction characteristics,typical pavement structure and construction technology of full depth foam cold recycling through theoretical analysis,indoor and outdoor tests and other means.It mainly includes the following aspects:Firstly,through physical tests and numerical simulation,the evolution behavior of long-term service performance of asphalt pavement is analyzed.Combining the pavement conditions of Tianjin Avenue,a service performance prediction model is established,and the maintenance opportunity and optimal technical scheme for trunk highways are determined.Secondly,the indoor test evaluation of foam asphalt cold mixture was carried out,and the optimal foaming temperature,water consumption,moisture content and cement consumption were determined,and the optimal foam asphalt consumption was proposed.The compaction characteristics of full depth foam asphalt cold recycling pavement were studied,the best mixing time and molding temperature were obtained,and the influence of various factors on the compaction quality of foam asphalt cold recycling mixture was explored.Thirdly,the design parameters of the full depth foam asphalt cold recycling pavement structure are analyzed,and the method to determine the structural design parameters according to the damage stage of the old base is proposed.Through practical engineering application,the construction machinery combination,rolling times and rolling speed of full depth foam asphalt cold recycling are determined,and the construction technology and quality control measures of full depth foam asphalt cold recycling mixture are proposed.Finally,compared with the traditional maintenance scheme,combined with the energy conservation and carbon reduction goals in highway construction under the national "double carbon" strategy,the energy consumption,carbon emissions and economic benefits of the full depth foam asphalt cold recycling technology are comprehensively analyzed,indicating that the full depth foam asphalt cold recycling technology can reduce energy waste and carbon emissions,and has significant economic and social benefits.