object Pass through the polySurface Maya imported scene.

Hello guys, I have imported a fbx scene which is created in Maya and my surface is poly Surface right now i am just dropping the cube using rigid body but it pass through the surface. i have also applied Mesh Collider also tested with applying box collider on both of them. but got no result.

can anybody point me out where is the problem. i am pretty new in unity. any help will be appreciative thanks.

Have you add rigid body to surface also?