Columnar mud sampler capable of sampling layer by layer

The utility model discloses a columnar mud sampler capable of stratified sampling, and relates to the technical field of columnar mud samplers, the columnar mud sampler comprises a rod and a replacement assembly, the middle part of the rod is sleeved with the replacement assembly used for differentiated impact force, the replacement assembly comprises an impact block, an inner cavity, an elastic sheet group, a conical surface, a screw cap and an inclined surface, the inner cavity is arranged in the impact block, and the elastic sheet group is arranged in the inner cavity. And the impact block is slidably installed outside the rod through the inner cavity, three elastic piece sets are annularly and fixedly installed at the middle end of the bottom of the inner cavity, conical surfaces are formed in the outer sides of the tops of the elastic piece sets, a nut is arranged at an opening in the top of the inner cavity, and the nut is engaged with threads on the inner side of the top of the impact block through thr