Study On The Relationship Between The Degree Of Compaction And Deflection Of Road Material

With the rapid development of national economy,more and more highway constructionsare constructing or preparing to construct. A lot of problems emerge in the large-scalehighway construction, one of which is the insufficient degree of compaction of the subgrade.Traditional compaction degree detection methods include cutting-ring method and pouringsand method and pouring water method and so on,but all the methods belong to damagedetection methods which can destroy the integrity of the road structure.Also, the testing dataresults are easily affected by the skill level of operators. In addition, all these methods areused after completed compaction,which can not measure the degree of compaction in theprocess of rolling.So a new detection method is needed,which can accuracy measure thedegree of compaction in the process of rolling.ZFG3000hand falling weight deflection is an instrument which can detect road structuredeflection rapidly. It has the advantages of convenient operation and short testing period. Oneoperator can measure the degree of compaction easily. Because its intelligent test process,theresult is tiny affected by the operator and the influence factors of external conditions. Thispaper chooses soil, cement stabilized soil, graded crushed stone and cement stabilizedmacadam as the research objects. For the first, get maximum dry density of the materialthrough indoor compaction test. Secondly, prepare objective compaction specimen accordingto the maximum dry density of material. Thirdly, get deflection value of the test piece byZFG3000, and fit curve of deflection value and degree of compaction. Fourthly, check thesimulation curve by in-situ test validation.This paper obtaines regression equation of soil, cement stabilized soil, graded crushedstone and cement stabilized macadam according to experiments indoor and outdoor.It verifysthat We can get the degree of compaction according to deflection. It provides the theoreticaland experimental support for the nondestructive testing,it puts forward a new direction ofnondestructive testing for the future.