Comparison of tunnel blast design models

Blast design has direct influence on the time consumption and construction cost of drill and blast tunnels. Two tunnel blast design models based on parallel hole cut, NTNU blast design model and Swedish blast design model, are discussed and evaluated in this article. Both models suggest smooth blasting and in both models cut design depends on drill hole length and empty hole diameter. For lifter and stoping holes the Swedish model gives higher burden values, indicating a lower number of holes. Generally, The NTNU model gives longer uncharged length which indicates lower explosives consumption.