I am trying to mount my 60" Sharp Aquos's bracket to the wall in my living room, the TV weighs 38 Kgs (83lbs). The problem I am having is I have never seen a wall like this before and dont know how to proceed. I was expecting there to be studs behind drywall but when I try to use a needle type stud finder I found the needle would not penetrate the wall. I opened an electrical outlet on the wall to find the wall is a sheet of concrete about 12mm (1/2 inch) deep with about 9mm (1/3 inch) of dry wall directly behind it so the wall is 21mm (.8 inches) thick total. I tried searching the other side of the wall which is made of only dry wall and there seems to be only one stud (maybe a stud) about 80cm away from the door (in Japan building code for wall studs are 455mm spacing).
Since concrete is rather robust compared to drywall could I just get away with mounting the bracket directly to the concrete with just using plastic concrete anchors and screws? If so what diameter and length should I use? If not what would be any of your suggestions?
Just to note the building I live in is a concrete structure and does not have a wood frame.
Thank you, for any information or suggestion.