Sure. If you laid them down and pegged them tightly and left them for awhile it would kill the weeds and everything else under them. But no water or air would be getting through and by the time you were done, the soil under it would be dry and cracked with no earthworms or anything left.
People do the same thing with clear plastic (called solarizing). The benefit of that is that it holds heat, so the top layer of the ground heats up enough to kill the weed seeds. The tarp won't do that, so if you killed all the weeds with the tarp and then tilled that spot, you would have a new crop of weeds again instantly.
If you just want to smother weeds, you can do it better with layers of newspaper. The newspaper is more breathable, lets air and water through, and it eventually breaks down and feeds the soil. Lay down multiple layers of newspaper and put soil and compost on top of it.