The Research On High And Low Temperature Performance Of Cold-recycling Of Emulsified Asphalt

The construction of asphalt pavement in China has gradually developed into the maintenance period from its early one. The traditional way for pavement is to excavate the old roads and re-construct new roads, which will produce a lot of waste and occupy a large amount of land and contaminate surroundings, and meanwhile cause huge waste of resources in terms of constructing material itself. Cold recycled asphalt pavement technology can reuse the asphalt for the old pavement and upgrade the efficiency for the use of resources and protect the environment, which is an effective measure to achieve the sustainable development.This thesis studies the current situation at home and abroad, and carries out the recycle and examination of the asphalt in the RAP and after sieving it, the gradation of the RAP is confirmed. Meanwhile, it makes the evaluation of the performance of the emulsified asphalt, cement and aggregate used in the test, and further analyse the mechanism for the formation of the strength of the Cold-Recycling of asphaltthe. results shows that the performance index of filler meet the specifications. By the use of orthogonal design method, with choosing splitting strength, Marshall stability, flow value, compressive strength and void as index, the amount of cement, asphalt content, RAP content and total water consumption in mixture can be determined and in this way a group of programs for optimum mix proportion (program 1) can be gained. consideringeconomic and social benefits, another group of programs for optimum mix proportion (program 2) can be gained. Then after the comparative test, program 2 is proved to be the best mix proportion. Finally, with program 2 as the basic standard and by fixing three factors and changing another factor, the comparative test will be carried out to evaluate the performance of mixture in the high and low temperature .After large amounts of experiments, it is concluded that under the condition of the proportion for the use of cement, emulsified asphalt, old material and water as 3%, 3%, 70% and 4%, cold recycling mixture produced by the mix design has the high intensity and good performance in high and low temperature and can be applied into in the basic layer of high-level freeway, as long as the mix design is reasonable.