I have some expensive dog beds from dogbed4less that have an outer denim cover, inner waterproof cover and memory foam. My Mastiff just rips the bed apart with her paw. Foam is everywhere. What about the following one. Not like a normal dog bed.
http://www.wayfair.com/Kuranda-USA-Standard-Elevated-Chew-Proof-Dog-Bed-in-Almond-85-X-KDA1001.html
http://www.wayfair.com/Kuranda-USA-Standard-Elevated-Chew-Proof-Dog-Bed-in-Almond-85-X-KDA1001.html