Study On Smooth Blasting Technology For Subway Tunnel

Qingdao Metro Line 1 Wugui interval submarine tunnel is China's first cross-sea subway tunnel. At present,the world's sea tunnel project is relatively small, similar to the engineering experience is not too much.Application of drilling and drilling method of construction of the submarine tunnel project did not form a complete system. The author of this paper is involved in the key technology of subway tunnel construction in Wagui area of Qingdao Metro Line. In order to make the tunnel safe,efficient and rapid construction, the numerical simulation of the mechanical response characteristics of the surrounding rock is carried out. The smooth blasting technology is applied to the subway tunnel, and the harmful effects of the blasting are put forward. Vibration decay coefficient K, a value of the regression analysis.Achieved the following results:(1) Through the application of ANSYS / LS-DYNA software, the numerical model and the location of the measuring points were established. The influence of the hole spacing, the resistance line and the single hole charge on the rock mechanical characteristics was discussed.(2) According to the combination of rock blasting theory and numerical simulation, combined with the actual situation of the scene will be applied to the subway tunnel blasting technology,forming a reasonable smooth blasting parameters.(3) Combined with the blasting construction of the subway tunnel in the Wagui area of Qingdao Metro Line 1,the noise, fly ash and harmful gas produced by the blasting are analyzed and the concrete control measures are put forward.(4) Based on the least squares method, the vibration velocity of the subway tunnel blasting is analyzed by regression analysis, and the K and a values of the Qingdao subsea tunnel granite and the seabed depth are 30?40m. K = 76.2, ? = 1.46.