Study On Compaction Density Of Subgrade Filler Based On Shear Wave Velocity

Coarse-grained soil is a kind of filling commonly used in subgrade.Its compaction density is directly related to the quality of subgrade filling.Research on compaction density of coarse-grained soil based on shear wave velocity has practical significance in improving the test efficiency of compaction density of subgrade fillers.The key to obtain the compaction density of coarse-grained soil subgrade fillers is to establish the relationship between shear wave velocity and compaction density,and to obtain the shear wave velocity test method suitable for coarse-grained soil.Therefore,through the theoretical analysis,numerical simulation and laboratory test,this paper researched on compaction density of coarse-grained soil subgrade filler based on shear wave velocity.The main research contents are as follows:(1)Based on elastic dynamic and spheres-contact theory,the relationship between shear wave velocity and soil properties was studied.And the theoretical equation of coarse-grained soil compaction density and shear wave velocity was established.The influence of parameters in this equation was analyzed,and its rationality was verified by numerical simulation.(2)The factors affecting the results of shear wave velocity test were discussed.The influence rules and reasons of these factors on test results were analyzed.And a shear wave velocity test method for coarse-grained soil was proposed.(3)The shear wave velocity test using bender elements was carried out.The effects of coarse particle content,excitation source properties and wave propagation time identification method on shear wave velocity measurement were analyzed.And according to the test results,the theoretical equation of coarse-grained soil compaction density and shear wave velocity and the test method of coarse-grained soil shear wave velocity proposed in this paper were validated.57 figures,9 tables,and 117 references.