Characteristics of Vibration Waves Measured in Concrete Lining of Excavated Tunnel during Blasting in Adjacent Tunnel

The effect of a blasting vibration from an excavating tunnel on adjacent excavated is great importance for the stability and security twin tunnels. Due to relatively small distance between face concrete lining tunnel, impact could be significant should considered in practical project. In order control scales during excavation one minimize one, research based field-blasting tests performed tunnels presented this study. particle velocities caused by were measured analysed six rounds blasts. According waves, it was clear that peak velocity (PPV) each blast always induced cut blasting, therefore, maximum due mainly dependent blasting. PPV all blasts 15.55 cm/s, corresponding tensile stress 1.44 MPa observed lining, which smaller than strength accordance with one-dimensional elastic-wave theory. Moreover, attenuation waves varied different regions, they utilized demonstrate characteristics blasting; e.g., region along direction 1.12 1.79 times larger those opposite direction, difference increased increasing source. side close other tunnel. However, two aforementioned regions similar when measuring point source more 6 m longitudinal Furthermore, used evaluate improve designs tunnelling drill-and-blast method.