Orica Case Study: Managing blast vibration whilst increasing tunnel advance rates

Orica works with customers across the globe to solve the unique challenges faced at their operations.
Toyota City is located in north-central Aichi Prefecture, Japan. With low lying areas of Toyota City prone to flooding, Kajima Corporation was contracted to excavate the Anei River tunnel in order to increase drainage capacity. With granite rock too hard for excavation, blasting was the obvious solution; however, the tunnel ran directly beneath a residential area.
Orica proposed the use of the eDev™ II Electronic Blasting System combined with Orica’s SHOTPlus™ T software for design, modelling and vibration analysis. The Multi Deck Blasting technique was also used to allow Kajima to blast through the most sensitive areas of the project with half the number of blasts that might have been required using the conventional blasting technique, thus minimising delays to both neighbours and construction activities, wiping months off the project’s critical path.