Research purposes: The purpose is how to use the blasting subsurface excavat ion method for the metro shallow tunne l nearly under- passing ground high- rise bu ild ing on the prem ise of ensuring the safety o f ground building and construction security.
Research conclusions: Application of the upper and low er section bench method and tak ing measures of absorption o f v ibration along w ith fo llow ing the non - m illisecond detonato r blast sequence can effectively control the se ism ic effect caused by the tunneling w ith blasting subsurface excavation, achieve the tunneling footage and ensure the safety o f the ground bu ild ing. By contro lling the reasonab le parameters o f tunne ling foo tage of a cycle and theM ax. charge volume,the ground v ibration velocity induced by blasting can be controlled w ith in the standard lim it o f 2 cm / s to the g round building w ith the w a ll rock 's recovery depth less than 10 m, and it can avo id the secondary d isaster to the g round building. The eng ineering practice indicates under the condition of h igh strength of thew a ll rock, applicat ion o f shortdistance contro l b lasting techno logy no t only can ensure the crash ing degree of the w a ll rock and be easy to tag slag to achieve h igh utilizat ion rate of explosive ho le, but also can avo id the over- excavat ion and under- excavation when excavating the tunnel boundary due to the cu tt ing effect o f the v ibra tion- reduct ion hole to ensure the smoo thness of the boundary excavat ion and the stability of the w all rock.