With the ability to take on major projects that include the installation of cable and conduits using their trenching and trenchless divisions, splicing, transmission testing, cutover and joining puts Infrastructure Constructions (IC) in the unique position of being one of the few companies in Australia with this capability.
With over fifty personnel on board, six horizontal directional drilling (HDD) machines, a variety of trenching machines, excavators and cable hauling equipment, IC is able to undertake several projects for different clients at the same time, no matter where they might be located.
Communication covers approximately 30 per cent of all IC projects with underground power, water and low pressure sewer taking up the rest. Some of IC’s communication projects have included the relocation of up to 24 km of major communication assets through rugged bushland, 5.5 km of new fibre through highly sensitive bushland for a major mining company, and several major projects involving the installation of multiple conduits using HDD under major road intersection, rivers and escarpments.
IC has also taken on several major communication projects in highly congested areas, where HDD is the main installation method used due to major construction restrictions being put in place. This can be due to several reasons, including being unable to open cut a road due high traffic flow; minimal disturbance allowed to surface structures due to high residential areas, school zones or highly sensitive areas like national parks; and even the high density of existing buried services in the area that make excavation difficult and slow.Article continues below…
It is not rare to see several of IC’s HDD machines lined up down the street or through bushland installing numerous kilometres of communication assets, with each machine installing hundreds of metres of multiple conduits in one bore. These projects can involve both fibre and/or copper cable. A recent project where HDD was used saw ten Ø110 conduits being installed in one borehole over 170 m under a major railway corridor without any surface disruption being caused.
Another project required 1,360 m of Ø50 mm conduit to be installed through suburban streets and park land. All the work constructed in the park was completed with an excavator while the street work was installed using HDD. This eliminated any hazards that could occur especially when installation took place in front of a major shopping centre and school. No long open trenchers were required with only minimal traffic control needed.
One IC project that also relied heavily on HDD was a crossing of a major road intersection that required eight Ø110 mm conduits to be installed over 256 m. This project required the bore to be a minimal of 15 m deep due to future road excavations, as well as the added difficulty of tracking the bore head under a major traffic loop (traffic lights).
When taking on turnkey projects, IC knows that this usually requires both trenching and trenchless techniques. Where these techniques are required along the route is usually defined by the client but in some circumstances this has been discussed on site between the client and the contractor due to the location of existing services, environmental reasons or even ground conditions. In most circumstances when working in open bush land or on a dirt track the open trenching technique is used. When working in these areas consisting of hard rock where only a small conduits or even direct buried is requested, IC utilises a number of excavators fitted with rock wheels. These wheels only cut a 75 mm wide trench down to 1,200 mm deep but can penetrate the rock at a much quicker rate than most other methods, especially when encountering sandstone with ironstone bands, white marble or even granite.
Having one contractor construct a complete project without having to engage outside assistance can be a real bonus for the client. First, the quality of workmanship is more controlled. IC has heard more than their fair share of stories where several different contractors are on site, and one of these contractors produces an unacceptable standard of work – often resulting in an extension to the completion time, as well as extra costs to repair the problem. Both of these are unacceptable and there is no real need for this scenario to ever happen.