Is there an efficient way keep two identical copies of a 20TB RAID?

I work in two different locations. My work drive is 20TB. All data is essential. Currently I have 1 master raid and 2 time machine copies. On one location I work from the master raid. On the other location I work from one of the time machine copies. But working from the time machine copy is slow. I would much rather just have an identical raids. Problem is I need to update the copy on a weekly basis, and time machine does this effortlessly. But is there a way to do this without time machine and the added layers of folders that time machine creates. In other words, have two identical clones of the master without literally copying the entire 20TB of data over from scratch every week?