Analysis of the Stability of Ancient City Wall under Different Depths of Sapping by Numerical Calculation

Abstract

The width of the top of the wall LIANGZHU ancient city , which is called the first city in China reaches 40-60m. The sapping depth made by around environment such as wind and sand is increasing years by years. So the problem of stability of wide top ancient wall has been put forward. Under different sapping depths in ancient city wall, using finite difference soft FLAC3D, We can build calculation model to study the failure laws and mechanism of the ancient city wall under different sapping depths. The research shows that when the sapping depth is not enough large, the whole city wall is stable and local plastic failure occurs around the sapping place. With the depth of sopping increasing, the plastic failure area is becoming bigger and bigger and reaches much deeper into the wall, even reaches the top of the wall, and the soil displacement becomes larger and larger until the whole wall sliding. The sapping contributes to the damage of the wall, the potential slide opening appears in the sapping area, and in the wall through plastic area appears, leading to the whole wall sliding.