Friends would like to keep in place their wheelchair ramp during the winter, but forecasted freezing rain/snow would render unusable. The ramp is (porch) painted MDO ply over treated wood frame, with adhesive backed grip strips, resting on mortared brick walk and steps. Sand will provide good traction over the ice, but scratch/gouge the paint, as would rock salt. Don't know what effect calcium chloride and such would have on the wood. Feedback greatly appreciated.