为了研究不同跨度地下洞室的动力响应特性,选用小直径炸弹,应用ANSYS/LS-DYNA有限元程序,对弹体垂直侵彻地下洞室进行了数值模拟,得到的侵彻深度与经验公式计算深度数值相近。研究结果表明:洞室埋深为5m时,拱顶处受力最大,14m以下小跨度洞室拱脚部位受力较大,24m以上大跨度洞室拱肩部位受力较大;洞室埋深为10m时,拱脚部位受力较大,位移响应最为剧烈,这些部位为结构的薄弱环节,在设计中应采取加强措施。

In order to research the dynamic response characteristics of underground cavity with different spans, numerical simulation of the vertical penetration of the projectile into the underground cavity was carried out by adopting small diameter bomb(SDB) and using ANSYS/ LS-DYNA finite element program. The abtained penetration depth was similar to the depth calculated by emprical formula. The research results showed that when the depth of the underground cavern was 5 meters, the stress at the vault was the largest, and the stress at cavity arch with small span(below 14 meters) was larger, while the stress at cavity spandrel with big span (above 24 meters) was larger. When the depth of the underground cavern was 10 meters, the stress at arch springing was large, the displacement response was the most severe. These parts were the weakness of structure, therefore strengthening measures should be taken in design.