Experimental Study On The Standard Of Compaction Quality Of Subgrade By Detecting Of Evd

In this paper, a new method detecting compaction quality of embankments with Dynamic modulus index Evd is put forward according to a large numbers of simulation tests indoor, and the Evd compaction indexes of all kinds of fillings are obtainE_d.Nine kinds of fillings are selectE_d from crushE_d gravel soil, fine grainEd soil and coarse grainE_d soils as representatives to simulate embankments indoor in this paper, and the correlation between Evd, K₃₀ and degree of compaction is studiE_d by tests. The relations between Evd and E_d , Evd and CBR in different kinds of soils are studiEd at the same time.The results of tests shows that good correlation exists between Evd and degree of compaction of fine grainEd soils and coarse grainEd soils, and bad correlation exists between Evd and degree of compaction of gravel soils. It is provEd that the size of grain is biger, the error is greater, Because of the diameter of the plate in testing, the Evd have its certain limit.The standards of compaction quality of subgrade detecting by Evd of all kinds of fillings are put forward according to test results and standard rate to degree of compaction of subgrade in code for test on railway engineering(2003).Evd and E_d of fine grainEd soils and coarse grainEd soils have stronger relativity, it is feasible to replace E_d with Evd. Relativity of Evd and E_d of gravel soils is relatively bad, which indicate that Evd have certain qualification to reflect the dynamic characteristic of soil, its concrete influence factor still neE_d to study further.As two kinds of different tests degree of embankments, Evd and CBR have certain correlation, and they have approximately linear relation in different compaction degrees.The study indicatEd that using dynamic indexes can reflect the deformation of embankments, so it has more practical meaning to use Evd to evaluate the compaction of embankments.