Abstract:The paper investigates the exterior design and the joinery of the bracket sets (dougong) installed under the eaves on the fifth floor of the Sakyamuni Pagoda built in Ying county, Shanxi province, in 1056, by using 3-D laser scanning technology and computed radiography. The results of these investigations indicate the following: First, the full and single standard units of zucai and dancai are 1.2 chi (20 fen° ) and 0.85 chi (14 fen° ) long respectively, and one cai is between 0.5 and 0.6 chi thick. Second, the construction ruler (absolute measurements) and the modular (caifen) system complement each other well; more precisely, the construction ruler was used to determinate the bay length, purlin span, and bracketlength, whereas the modular system was used to design the particularities of dou and gong. Third, the design of the mortise and tenon joints in a dougong was controlled by both the construction ruler and the modular system. In addition, the paper propagates 3-D laser scanning and computed radiography technology as efficient and sophisticated digital tools for field survey and research, while pointing out the limitations due to local conditions and the narrow scope of this study.
