Staging – DMCivil

Author: Paul

  • DM Civil Concrete Capability

    DM Civil Concrete Capability

    Since DM Civil was founded in 1976, concrete work has often featured as a component in any contract, if not the key scope of works. Our company has built concrete elements and structures including:

    • Pre-cast and insitu-cast vehicle and pedestrian underpasses
    • Pre-cast and insitu-cast boat ramps
    • Insitu-cast storage dam spillways
    • Insitu-cast trunk watermain valve pits
    • Insitu-cast industrial and municipal use building structures
    • Insitu-cast main sewer access chambers
    • Precast stormwater main drain bridges
    • Precast road bridges
    • Insitu-cast ground tanks

    Potable water retaining ground tanks have been build by DM Civil since the 1990’s when the Araluen Golf Course Estate storage tanks were constructed in Roleystone. Since then, we have constructed the base ring beam and associated works for the Carabooda 60 megalitre main water supply, the Coral Bay 800 kilolitre water supply main tank and the Dalwallinu town supply ground tank.

    The Dalwallinu 2 megalitre ground tank and associated works was constructed for Water Corporation in 2018. The 20m diameter tank was cast insitu with 6m high walls, cast in 3 lifts and covered with a concrete roof. The roof was constructed using precast beams and panels, supported by precast columns, which were topped with an insitu-cast sloping cap. The construction was subject to strict quality assurance measures to ensure longevity of the asset and to comply with drinking water standards.

    The Dalwallinu ground tank construction comprised the following steps:

    • Bulk earthworks for the tank foundation by removal of unsuitable material and replacement with clean sand fill to subgrade level;
    • Installation of MSCL outlet pipework below the tank base;
    • Forming and pouring a concrete block trial mix for testing prior to tank construction;
    • Placement of a mass concrete blinding layer as a firm and level access to the tank area and for installation of the tank base steel reinforcement and wall starter bars;
    • Forming and pouring the tank base with 40MPA special mix concrete;
    • Placement and propping of wall formwork first lift including injection tubes for hydrophilic seal material;
    • Fixing of first lift reinforcing steel including incorporation of a stainless steel manway code welded to the reinforcement;
    • Forming and pouring second lift of wall including surface treatment of first lift top edge to ensure a waterproof seal;
    • Forming and pouring third lift of wall to 6.0m level including formed top pockets to incorporate roof beam and surface treatment of second lift top edge to ensure a waterproof seal;
    • Craning into place over starter bars, RC columns that were precast on site and propping in place and injecting epoxy grout in tubes incorporated during the precasting process;
    • Craning into place precast Delta Beams to bear on the third wall lift pockets and the precast RC columns;
    • Craning into place precast Delta Core panels to span between beams with subsequent grout fill to perimeter units;
    • Pouring a single roof slab of the Delta Beams and Panels to form a homogeneous cover over the tank;
    • Fixing the ventilator units and access hatched into the concrete roof;
    • Fixing of the tank external stainless steel tank filling pipework and the internal fibre reinforced plastic (FRP) pipework and supports;
    • Construction of the FRP internal and external access ladders and security screens;
    • Filling and leak testing of the tank for commissioning.

    DM Civil has now commenced construction of a similar design of ground tank located at Lakelands on the northern side of central Mandurah. The 850 kilolitre tank is being built to Water Corporation standards to the same design as the Dalwallinu tank, but with a reduced capacity. Our experience on the Dalwallinu project will be used to ensure that the same high standards are maintained for this project and that our workforce continues to gain and retain the skills and expertise for this scope of works.

  • DM Civil Tesmec Trenching Rock Saws

    DM Civil Tesmec Trenching Rock Saws

    DM Civil is pleased to present our refurbished Tesmec trenching rocks saws. Both machines have been operating reliably in our fleet since 2010. Our Tesmec TRS1300 ‘Super’ is an 80 tonne machine driven by a 600 horsepower Cat C16 engine. Cut widths can be varied from 675mm to 950mm. The later model Tesmec TRS 1475 is a 100 tonne machine also driven by a 600 horsepower Cat C16 engine. Cut widths can be varied from 675mm, 1,050mm or 1,250mm. DM civil has re-engineered the booms to allow maximum reach, in order to produce up to 3.5m depth of cut, to an alternative shortened configuration with 2.5m depth of cut. The adjustment is achieved by removing a 1.0m long bolted box section and rejoining the boom. The drive chains are then shortened to suit the new length. The shorter boom lengths are designed to provide a steeper angle of attack for the rotating cutting pads, thereby providing more leverage for the trenching operation with corresponding faster production.

    Due to the stringent requirements on site for the coming campaign, our machines have been broken down to expose all guards and mechanisms to allow for complete inspection and cleaning to meet the most stringent quarantine standards. Pressure blasting, steam cleaning and some full component replacement has taken place over a 3 month period.

    Both machines have been grit blasted and repainted, including guards, cowlings, railings and other attachments, which were removed for the process. Track and roller guards were individually detailed, and track rollers replaced with new in most cases.

    The cabins were stripped out of all trim and the steel shells repainted. Rewiring and fitting of new GPS units, opposite side-view cameras and instrumentation upgrades were carried out while the cabs were bare. The side view cameras now provide additional vision on the opposite side of the machine for increased safety in addition to the ground based spotter. The cabin trim internals including sound and heat insulation and operator chair have been renewed to meet quarantine requirements.

    The remote site also presents challenges in reliability and the requirement for timely repairs in the event of a breakdown. A suite of spare parts will be available on-site and will include main drives, spoil conveyor belt, radiator, GET’s and GET keepers.

    Our rock saws have been used from the Great Southern region to the Darling Scarp, Perth metropolitan, the Mid-West, Goldfields, North West Cape and the Pilbara. Each area has its own challenging rock types including sedimentary, metamorphic and igneous. The former are generally able to be removed at reasonable production rates, while the removal of granitic rock depends on the degree of weathering and fracture pattern. This degree of weathering is also influenced by the depth of cut required.

    Operation and maintenance of trenching rock saws is a key element in the capacity to guarantee production. The standard site crew required for both machines consists of an operator and a ground based spotter, who continually monitors conditions around the machine, including potential interaction with other vehicles. This may include operating a trailer mounted water source for dust suppression and cooling of drive mechanisms. The spotter is in contact with the operator by two way radio and visually around the cab and the opposite side two way camera.

    The benefit to the client in engaging DM Civil to trench for pipelines and services in hard ground or even pindan sands, is efficiency. That is value for money. In moderate to hard ground conditions, the usual requirement for provisional rock payment allowance can be limited to only high strength unweathered igneous rock.