Sounds potentially dangerous. I'd start with either a professional fabricator or solid wood 6x6 blocks cribbed and with an angled "ramp" cut. 3 ties wide x however long for the ramp. All tied together with threaded rods/bolts, 2 per layer. They'd sure be heavy to move around though. Maybe a hand truck/dollie or add wheels to them so as when tipped up the wheels touch and allow them to be rolled around. You could get about 12" high this way with 3 layers. Not perfect but good... Add a 2x in somewhere to get closer to 14".
Be careful, be safe. Consider the liability.