Comparative Study On Interlayer Characteristics Of Continuous And Discontinuous Paving Asphalt Surface

Continuous paving is a new paving technology developed abroad.It differs from the traditional paving technology in that the upper layer and the lower layer are paved simultaneously,and then rolled together to achieve the required compaction.In the process of rolling,because of the influence of heat in the lower layer,the rolling time will be increased and the compaction will be more sufficient.There are two construction techniques for continuous paving.One is "Hot on Hot",the upper and lower layers of different mixtures are paved at the same time,and the last two layers are compacted and formed together.The other is"Hot on Warm",the lower layer is paved and then fully compacted,then the upper layer is paved and finally compacted again.This paper simulates the continuous and discontinuous paving construction technology.By determining the gradation combination,the thickness of upper and lower layers and the number of compaction,to make two-layer Marshall specimens with different requirements.Firstly,the continuous paving asphalt mixture is compared with three kinds of intermittent paving asphalt mixture with different interlayer treatments.Then according to the characteristics of continuous paving,through shear test,splitting test,bending test and rutting test,the influence of different compactness of the lower layer and different temperature of the lower layer on the continuous paving of asphalt mixture is analyzed.Through the analysis of laboratory tests,it is concluded that,compared with intermittent paving,the interlaminar properties of continuous paving asphalt mixture are better than that of discontinuous paving.In the study of the compactness of continuous paving,it is found that,there is an optimum eompactness of the lower layer,which makes the pavement performanee of asphalt mixture the best.And when the upper mixture is spread,the higher the temperature of the lower layer is between 35 and 115 degrees centigrade.The better pavement performance of continuous paving asphalt mixture.Comparing shear test and splitting test under different environments,it is found that the strength of double-layer asphalt mixture is the greatest at low temperature,followed by normal temperature,and the smallest under freeze-thaw environment.The research conclusion has certain guiding significance for the research and application of asphalt mixture continuous paving technology.