What are the architectural techniques of Dong wooden structure buildings?

Dong people's wooden structure construction skill is the most outstanding performance of national folk traditional culture in Sanjiang County, Guangxi. During the Three Kingdoms period, the ancestors of Dong people lived by trees, which was called Gan Lan, and gradually formed the skill of building wooden structures. Sanjiang Dong wooden structure buildings, represented by Yufeng Bridge and Drum Tower, are not only beautiful in appearance, but also unique in technology. The whole building is connected by tenons, beams, arches and columns, without any nails. The structure is firm and the connection is meticulous, which has high technical and artistic value. ? Drum Tower, also known as "Luohan Tower", is a tower-shaped "one-horned tower" with giant wood as the central pillar, which stands tall in the Dong village and becomes the spiritual symbol of the Dong family. The bridge across the river is a "bridge of life" connecting Yin and Yang, and it is also a "bridge of happiness" in the minds of the Dong people to protect the village and collect money. Therefore, it has been generously carved and decorated, making it a magnificent building integrating pavilions, towers, corridors and bridges. Various patterns on buildings, bridges and carved beams and painted buildings have entrusted the Dong people's good wishes and aesthetic pursuit of good weather and abundant crops, which is a concentrated expression of Dong cultural characteristics. Dong people are born artists, and folk craftsmen have superb architectural talent. When they build buildings, bridges and houses, they don't need a drawing. The whole structure is by heart. They can make buildings and bridges with different styles and beautiful shapes with simple bamboo sticks as the criterion and unique "handwriting of the ink man" as the design annotation. Exquisite design and beautiful shape are amazing. ? What is worrying is that due to the lack of successors of Dong architectural craftsmen, the lack of wood sources, the fire prevention ability of wood structure buildings is extremely weak, easy to be damaged and difficult to regenerate, and the Dong wood structure buildings and related skills are in a continuous crisis. Only by strengthening the rescue and protection work can the Dong people's wooden building skills be passed down from generation to generation. In 2006, Dong's wooden architecture skills were included in the first batch of national intangible cultural heritage representative projects.