The Melbourne Metro Stations will be built as trinocular caverns, where three overlapping tunnels will be mined by roadheaders to create a platform width that will be around 19m – one of the widest metro platforms in the world.
Two temporary acoustic sheds up to 20m high enclose construction sites within the CBD to minimise the impact on residents, businesses and the local community, from the construction of the stations. A system of louvres on the outside of the acoustic sheds help to control clean air flow into the tunnel. The ventilation system was also designed for environmental noise limits while balancing required air flow into the tunnel.
Since construction began, Grydale has designed, manufactured and supplied the following dust collection systems, in line with the ventilation design:
CBD North – 4 x JMS-60-MES (60m3s, mobile, electric, drag skid units).
CBD South – 5 x JMS-60-MES (60m3/s, mobile, electric, drag skid units). CBD South had further space constraints, so these units were customised to have four roof-mounted fans to provide a reduced footprint so dust collectors can be located within the acoustic shed.
Parkville – 1 x JMS-30-MDT (30m3/s, mobile, diesel, track unit) and 3 x JMS-10-MES (10m3/s, mobile, electric, drag skid unit) were rented to provide short-term dust extraction at source.
Tunnel Cross Passages – 2 x JMS-10-MEC-XP (10m³/s, mobile, electric, castor wheel units). These units were designed for the tight space constraints of tunnel cross passages. The castor wheels allow units to slide onto the platforms in the cross passages for the duration of construction.
Rental Units – 3 x JMS-30-MDT (30m³/s, mobile, diesel, track units) have been utilised for dust extraction within backend works at various project work sites.