When I walked on the road, I happened to pass a pool of mud. Somebody had already set some blocks of stones and bricks on the mud from one end to other end in order to pass it. I could pass it by treading on the blocks of stones. What do you call such a temporary arrangement to walk on?
The structure you are looking for are called stepping stones. The name is applicable to any walkway of that type, whether temporary or permanent.
It's "an improvisation" or an improvised solution
an improvised bridge, for example
I think you may refer to it as a temporary/emergency walkway:
- a passage or path for walking.
- or an emergency stone path.
If you don't specifically refer to a road, it's a rudimentary workaround.
"rudimentary" definition: basic, simple, not elaborated; of a primitive kind; very imperfectly developed.
"workaround" definition: a plan, method or process of dealing with a problem without eliminating it (often used in computer science).
makeshift walkway, or simply makeshift, is what I would call such an arrangement.
a temporary expedient or substitute: We used boxes as a makeshift while the kitchen chairs were being painted.
Also, makeshifty. serving as, or of the nature of, a makeshift.
Alternately, consider jury-rigged walkway.
: done or made using whatever is available; "crossed the river on improvised bridges"; "the survivors used jury-rigged fishing gear"; "the rock served as a makeshift hammer"
I think you might be looking for the adjective ad hoc:
- Ad hoc concerned or dealing with a specific subject, purpose, or end.
Unfortunately the difficulty index is a bit high for this word :/
I crossed the ad hoc walkway today