On a trip to England years ago, I saw an old fence whose posts had rotted off at ground level. The rest of the fence was still in good shape, so its owner had replaced the belowgrade post sections with concrete splints. I’ve since mended my fences using the same solution, with excellent results.
I built a form about 4 ft. long, with sloping ends and one sloping side, as shown in the drawing. For each splint, three short pieces of 3/8-in. galvanized pipe are mounted on the form’s axis to secure two lengths of 3/8-in. rebar. Two of the pipe sections are in the above-grade half of the splint, and act as sleeves for 5/16-in. bolts during installation.
Before filling the form, I lubricate the sides with a little axle grease to aid in removal. Nearly every splint I’ve cast has been with the leftover concrete from some small household job.
Sidney McGaw, Albany, CA