软硬互层地铁区间矿山法施工爆破影响范围研究

以福州地铁1号线上达区间为工程背景，运用ANSYS有限元软件对矿山法施工的爆破影响进行了动态模拟。提出3种开挖面至软硬互层交界面距离分别为7，11，15 m时的3种工况，结合隧道的实际断面形式建立计算模型，重点研究爆破开挖对不同工况周围地层位移、主应力以及振速的影响，并提出合理的施工方案。结果表明:采用矿山法开挖至软硬互层交界面距离大于11 m时是安全的，基于此进行爆破施工范围优化，可减少后续盾构掘进难度。

Study on Effect of Blasting Construction Range of Metro Section with Mining Method in Soft and Hard Interaction Stratum

Based on the section between Shangteng and Dadao in Fuzhou metro line one, the blasting effect of construction with mining method is mainly simulated dynamically by the finite element software ANSYS. The distance between the excavation surface and the interface is 7,11,15 m respectively. A calculation model is established combining the actual section form of the tunnel to mainly study the effects of blasting excavation on stratum displacement, stratum principal stress and vibration speed under different conditions. In addition, a reasonable construction program will be made based on the simulation. The conclusion shows that when the distance between the excavation surface and the interface is 11 m, it is safe, based on which,the optimization of blasting construction range is carried out so as to reduce the difficulties of the following shield tunneling.