A centrally post-tensioned column
Fig. 11-8: Centrally post-tensioned stone columns
Fig. 11-8 shows three piles of stones which form stone columns in a park. This landmark is similar to the wooden block column model shown in Fig. 11-6. A steel bar, with one end anchored into a foundation below the stones, is threaded through pre-made central holes in the stones. The bar is then tensioned to make the stone blocks act together similar to a single member.