Is your TC parked on black top or concrete? If so, use concrete nails to anchor the jack feet to the surface. If on gravel, dirt or grass, drive 2 metal stakes on the outboard front or rear and side of each jack foot to anchor them and keep them from lifting or moving around. It the terra is soft, use 3 longer stakes on each corner.
Someone on here asked about how to lash down their TC in anticipation of a hurricane coming through. I think the hurricane missed, but it brought out a lot of good answers. Purchase two 30 foot, 10K pound trucker/jeeper ratchet straps and lay them over the roof lining them up so as to miss any fragile elements up there. Then with 4, 2 foot long screw anchors and twist them into the ground outboard of each corner close enough to reach the ends of the straps. If you are really hard core, use some 2x4 shims to protect the edges of the TC top under the straps. I'm thinking a good move if on dirt would be to put 4 pre poured concrete garden pads or 18 inch x 1-1/2 inch plywood pads under each jack foot.
I don't know, this seems like belt and suspenders to me.
jefe