btw, did u lay steel frame when u lay those cement/concrete on the lawn or earth? if not, be prepare to have 'cave in' later........if there is too much weight over it....just telling my experience.

just imagine a bra without underwire..........it goes down. some tiles broke because the 'support' part is weak.........the best, put a steel bar as what my contractor said......even a tractor also can move over....