Bucket arch is a kind of structure in Chinese traditional architecture, which is composed of several arch structures and has the function of support and decoration. In building construction, bucket arches are often used to support eaves and roofs, and can also be used as a decorative element.
Therefore, the bucket arch usually refers to the central position of the bucket arch, that is, the geometric center of the bucket arch. Specifically, the middle of the bucket refers to the position of the left and right center lines of the bucket arch.