Can I move a fixed swinging arm/change it's length, while maintaining the arc of the swing?

Question

There is a floating dock which is affixed to the shore using two 10ft lengths of pipe, one at each end. They are attached perpendicular to the shore. They use ball lock pins to stay attached, allowing the dock to rise and fall with the ebb and flow of the tides. The issue is that the dock is too long, and needs additional lengths of pipe at different points along the shore. Unfortunately, the shore is not uniform in length, it actually varies greatly. When additional lengths of pipe were added in between, since they were varied lengths(anywhere from 5 to 8 feet) they did not swing at the same arc as the 10 foot lengths, which caused the dock to buckle, and be unsafe for usage. Is there a formula which allows me to place a new pipe at a non-perpendicukar angle, and maintain the same arc swing? I apologize for the length of the question, I am not a mathematician.

Answer 1

The size and shape of an arc is determined by the radius and the angle the arc subtends.

Thus, pipes of different lengths cannot create equal arcs.

Since there are already 10 feet pipes what prevents the inclusion of others of the same length anchored on the shore parallel to the edge of the dock?