Usage patterns
〈物〉に支柱を立てるto set up a prop/support pole for something
I set up a support pole for the tomato seedling.
〈物〉の支柱となるto become the pillar/mainstay of something
He became the mainstay of the team.
支柱を固定するto secure a support pole in place
I secured the support pole in preparation for strong wind.