Research Of Compaction Quality Controll And Rapid Detection Technology Of The Natural Gravle Subgrade

With the implementation of the strategy for the development of the western regionsdeeply， highway construction in Xinjiang area is being in the period of great developmentexpressways has started been constructed in autonomous region.Because of the specialnatural environment in Xinjiang area， most of subgrade filler is natural gravel， and theresearch of natural gravel as as the roadbed filler is less at home and abroad，the relatedtechnical standards and criterions were relatively lack， the natural gravel roadbedcompaction quality control technology and rapid detection methods can not meet therequirement of engineering. In the face of these problems， combining the Xinjiang area inthe construction of expressway， using theoretical analysis， laboratory experiment and fieldtest， the natural sand gravel subgrade compaction quality control technology and rapiddetection method and evaluation standard.（1）Gradation characteristics of natural gravel roadbed filler from highways isanalyzed， Conclusion is that the natural gravel stone content vary greatly， but which isconcentrated in between30%~70%， belongs to the middle class of the earth rock mixture，so which can form a mosaic structure good，and can get high strength in filling of subgrade.（2）The indoor compaction test of natural gravel is done with surface vibratingcompaction method， results show that the content of stone， gradation and vibrationparameters are the main factors that influence the natural sand vibration compaction， andwhich are the main control parameters. Stone content is greater， the dry density of fillerincreasing more， the roadbed compaction time and rolling power can be reducedcorrespondingly； within a certain range， vibration time is longer， the greater the packingdensity； the dry density of filler under the influence of gradation， water content lesssensitive.（3）The natural gravelcom compaction tests are carried depending on the project ofexpressway from Akesu to Kashi.Quality control measures and construction technology ofsubgrade with natural gravel were determined. At the same time， the subgrade compactionquality was tested by the method of settlement， bearing plate method， sand filling method，PFWD etc..（4）By researching the correlation between the settlement， compaction， static modulus and dynamic modulus of elasticity of natural gravel roadbed，put forward the rapiddetection method of natural gravel roadbed compaction quality， which the surface settlementcontrol method as the auxiliary method，the PFWD method as the quantitative detectionmeans， the sand filling method as the calibration standard， and gives the correspondingevaluation criteria.