Special Roadbed Construction Key Technology Research

With social and economy progress in the West China and booming of the highways construction, wind-aggregated sand and over coarse-grained embankment have been a common roadbed in advanced freeway construction in the West China. Based on the existing results abroad and home, combining with the characteristic of the NeiMengGu BaLaGong-XinDi-MaHuangGou freeway area, the compacting properties of substance and the dash-compaction technology using in the highway subgrade in the project area are studied systemically. In the meanwhile, the paper has studied the Rayleigh wave applied to the testing of compaction degree of special roadbed emphatically.Based on the laboratory tests and the theoretical analysis, the physics properties and the mechanics of substance are studied; Based on the heavy compaction test, the compacting properties and the compacting mechanism of substance are studied, and the influencing rules of the compaction test based on the laboratory tests are analyzed; Using the vibration table, the vibratory properties and the compacting mechanism are studied, the rules and the degree that the vibratory parameters influence the vibratory compacting of the substance are analyzed; On the basis of many reference information, lots of local compaction tests have been done and dash-compaction technology has been systematically studied; Following these studies, the compaction standard is obtained firstly, including the choice of the biggest dry density and the compactness standard and the mensuration of compactness.In the course of scene quality testing, by means of adopting the technique of Rayleigh assorted the determine of tested density of the substance and compaction, by means of a great deal indoors test and field,satisfying effect on roadbed compaction degree test is received.