To answer query raised by you, one needs to have better understanding of trade practices of that industry, factual & technical status, role and usage of these tracks as well as boulders etc.
Without knowledge and accuracy of these factual aspects, it is risky to apply legal provisions and arrive at any views on the query raised by you.
Are you talking about boulder means those things which are put / attached between two tracks of railway-line, to maintain continuity of the track and to ensure safe passage of railway?
And if so, are these boulders are easily removable and re-used at other place for similar purpose or not?
One more, question is whether these railway-lines are themselves immovable property or not and why?
And so on .... there will be more questions on many factual aspects, depending upon answers on initial questions.
So it seems to be that discussion on public forum may not give you any concrete views on the subject query unless someone has already studied and dealt with the all relevant factual aspects.