Can i use hay for chicken litter on cement floor?

There are better alternatives. Hay is not very absorbent, and because it comes in long strands which get stuck together with poo, its hard to pick up the droppings and keep the floor clean. Also it usually contains dust and allergens which may affect the chickens' breathing, they are very sensitive to dust and it can lead to bronchial problems.

Its best to use something like shredded hemp stems (Aubiose) or one of the other dust- extracted bagged litter shredded stuff which is specially made for bedding horses and is equally suitable for chickens. Many people use wood chippings, which ae fine so long as they don't come from prunings that contained thorns, as these may cause foot problems if the hens tread on the sharp bits.

As Sunflower said, hay is not good. Use the alternatives she suggested, or straw, or collect dry fallen leaves in autumn/fall.