I have a 60'x72' poll barn I'm building. I had a 6" thick floor poured since I'm going to have heavy machinery on it. They put fiber in it also. It was poured in cold weather last year and seemed to be a wet mix. Now the surface is pitted and flaked everywhere. So now the guys that did the job say they will do a 2" over pour and it will look great. I was talking to a guy that does concrete and he said the over pour will split all over the place. What do I do?