Based on the gobi-filler test of testing for subgrade on the second double line of Lan-Xin Railway

the difference and relation between the ground coefficient K30 and the static modulus of deformation Ev2 were analyzed; and the curve feature of ground coefficient K30 and deformation modulus Ev of four different kinds of fillers were summed up; also

the correlation between K30 and Ev were analyzed. With more information of the laboratory test

the acting factors for K30 and Ev2 were summed up. The results show that: ① The compaction quality of the soil is the main factor for K30

Ev1 and Ev2/Ev1. ② The nature of the filler is the main acting factor for Ev2 and it also has a influence on Ev2/Ev1. ③ The Ev2 is the characteristic parameter for the filler; it reflect the rigidity of the subgrade. ④ The K30 is the controlling index for compaction quality. ⑤ The correlation between K30 and Ev1 is closer

while K30 and Ev2 is slight; and different kinds of fillers have different correlations between K30 and Ev; the results reveal that the correlation is little with the checking indices become more disperse.