Meridian reticulated shell

This post was last edited by laisheng on 2010-12-9 at 22:09. A meridian grid shell is essentially a grid formed by dividing the central angles in the two diameter directions equally; since the arc lengths correspond to equal central angles, the middle part, except for the edges, forms a square grid, which is why it is also called a square grid shell. This bilateral radial structure was invented and patented as early as the 1930s by two British engineers; it was widely used abroad in the 1940s and 1950s. However, due to inherent defects in its structural strength, stiffness, and stability, numerous engineering accidents occurred, which led to this structure being almost entirely abandoned for use on tank roofs abroad. Therefore, the so-called radial shell patents in China are acts of plagiarizing others’ work, and their patents have been declared invalid by the patent office. http://bbs.hcbbs.com/viewthread.php?tid=619696&highlight=%D7%D3%CE%E7%CF%DF%CD%F8%BF%C7