Abstract:Abstract : Research purposes : Existing railway line often uses piling and other measures to control the disease,limited by concrete slab track, the object on track and operational security, traditional methods in high - speed railway are difficult to detect the effect of reinforcement. This paper presents a new idea of subgrade non destruction testing( NDT), Candies out seismic wave transmission imaging study from the subgrade left and right sides on subgrade body,and after subgrade piling reinforcement makes comprehensive tests for seismic wave transmission,drill exploration and !d multiple methods to detect effect of this method in subgrade nondestructive testing,to provide effective help to detect high - speed railway subgrade. Research conclusions :( 1 ) The proposed subgrade side NDT methods can acquire subgrade body more elastic parameters of rock and soil distribution image,such as vertical and horizontal velocity, Poisson Z ratio and elastic modulus,after which these parameters can be a better way to judge the state of the body,in particular,can get real - time soil Poisson ratio for each position in the field of subgrade body without resampling indoor testing, to facilitate judging the distribution of hard and soft soil and soil inside the subgrade. (2) By means of the methods of seismic wave transmission,drill exploration, Evd and excavation in the actual subgrade model,it is proved that: subgrade lateral seismic wave transmission detection method proposed in this paper can effectively reflect the extension direction and the surrounding dielectric strength of the embankment piles and other information to provide detailed information for the evaluation of the subgrade. ( 3 ) The proposed embankment lateral seismic wave transmission method can be used for high - speed railway subgrade NDT work without the channel dramatically reducing security risks $ to provide effective help for the subgrade maintenance and reinforcement and has a very strong guiding significance for railway subgrade detected in similar situations.