How to make 3d physics collision displayed when creating a TileMap?

New to UE4.
I’m creating a TileMap but noticed there is no 3d physics collision shown on the TileMap like above.(The cube around tiles is so-called 3d physics collision,am I right?)
Already set the collision thickness,choosed Use 3D Physics,added shape to tiles in editor,thought these decide collision but still nothing happened.Also I found there is no difference whether choose Use 3D Physics or not
Pls help.Mine is below.