Aaro were engaged to construct a multiplate tunnel inside the existing escape tunnel due to the existing structure exceeding its maximum load capacity by 15% and was in danger of collapsing.
The additional multiplate tunnel was used to reinforce the current escape tunnel bringing it back to its load rating reinstating the escape tunnel for operation.
This was completed during operation of the conveyor and around live services allowing the site to maintain production and operation during construction.
Access was tight making it difficult to install the plates but with additional lifting aids and some innovative thinking the crew were able to install the multiplate safely around the live services.
The scope of works included:
- Supply of labour, materials and specialised plant
- Removal of concrete invert
- Installation of tunnel plate / multiplate
- Shotcrete sealing ends
- Cementitious grout fill into cavity between tunnel plates
- Concrete invert reinstatement
