The tile is 12mm thk

This seems to be an oxymoron, ceramic wood. Can you better describe what you need to do?

It's a wood design ceramic tile. Size at 150x1200x12mm thk. Im wondering how to install it on concrete underslab. So the tile will be the ceiling finish directly mounted to concrete underslab

Here is a link to procedure for installing ceramic tiles on a ceiling and if these wood design ceramic tiles are of the same basic material, this procedure should work, although I must admit I would never install such a ceiling myself.
How to Install Ceramic Tile on a Ceiling | eHow.com (http://www.ehow.com/how_5110675_install-ceramic-tile-ceiling.html)

Thanks. Btw, would it be OK to nail it also to make it safer? Will the tile not crack while nailing it or drilling through it?

Can't nail ceramic.

How about if homogenous tile, can we drill on it to put the nail as anchorage?

If top side of concrete is subject to the weather u will have a problem with water(moisture) permeating from above. This will break down the adhesive holding power and tile will fall. Could hurt someone if falling at wrong time.

Nails will not anchor the tile with enough holding power and will not be too pleasing to the eye.

Have seen this done with manufacture wood which was really plastic. It was glued and screwed to concrete. Screws where counter sunk and covered with a glued in dowel. This was done to an area with a finish room above.

Chuck

Thanks Chuck. Contractor said screws will hold it. They are going to put 2 on each end then put putty and finish it to match tile. Hope it will be good enough. There is waterproofing above canopy
If top side of concrete is subject to the weather u will have a problem with water(moisture) permeating from above. This will break down the adhesive holding power and tile will fall. Could hurt someone if falling at wrong time.

Nails will not anchor the tile with enough holding power and will not be too pleasing to the eye.

Have seen this done with manufacture wood which was really plastic. It was glued and screwed to concrete. Screws where counter sunk and covered with a glued in dowel. This was done to an area with a finish room above.

Chuck