I recently built a roughly 5'X9' unmortared brick patio on a concrete base raised up on several inches of crushed stone and a couple inches of sand. The (very small) gaps between the bricks are filled only with sand. It is very solid, but I think I was a victim of poor planning, because I need to build up two steps from the patio to the back door of the house, but I'm realizing that if I lay something real heavy on the unmortared bricks like a wood-cased stone-and-sand-filled brick-topped step unit, the constant weight will make those bricks sink and the whole patio to unlevel, maybe crack, and generally get ruined. Is this so? If I were to spread out the weight so that it was on evenly distributed over the area of steps (maybe 3' x 4') would it be ok? I'm guessing the steps, once finished, might weigh as much as 500lbs. Maybe I'd be safer with just building wooden stairs, or would those be too heavy too?
it shouldn't really be called a "base" per se. It was a concrete pad of about 3 inches thick poured long ago that has split and become unlevel. It is what is underneath, but not a real base. Because it was poured at an angle away from the house, it is within 3 inches of the bottom of the pavers near the house, and 9 inches near the far edge.