The drill and blast method in tunnelling involves drilling a series of holes in a precise pattern, then filling them with explosives to break and remove rock. The design of the drill and blast pattern is crucial, as it determines the effectiveness and safety of the operation. It factors in rock type, tunnel size, and desired fragmentation. Proper sequencing and timing of blasts are essential to minimise vibration, control overbreak, and maintain the tunnel's structural integrity. Follow us at tu

Covering blasting with blasting mats or soil helps control fly rock and air overpressure by containing the energy and debris generated during the blast. Blasting mats absorb and disperse the shockwave, reducing the likelihood of fly rock projectiles being ejected from the blast site. Additionally, soil cover acts as a barrier, absorbing energy and preventing the propagation of air overpressure waves beyond the blast area, thereby minimizing the impact on surrounding structures and environments.