[Help] Dog crate mat that is not easy to destroy?

Hello, I have a dog who I occasionally need to crate.The only issue is that unless I am watching him he likes to destroy his beds.He gets an incredible amount of mental and physical stimulation, and will do this even if he has just come back from training all day, so I dont want any suggestions for doing more exercise, as he will do this even when tired, he just finds it fun and satisfying to destroy beds, and doesn't destroy much else.I dont want his crate to have a metal, hard floor to it.That is bad for his joints.I have spent hours on fitting soft foam dog matting that links together like puzzles and was a very snug fit, only for him to dig at it and manage to get it up.If I used horse rubber matting like the type used in stables, than I am certain he would not be able to get it up, let alone chew it.But I dont feel that is soft enough to help him when he is laying on it?What do you suggest?I try again with the foam matting? It took him a lot to dig it up, and if I use one that doesnt have puzzle links than it may be more difficult to destroy perhaps? via /r/dogs http://ift.tt/2qTjGf8