New Parallel Runway at Brisbane Airport

Background

The new parallel runway at Brisbane airport is not only a critical component in Brisbane Airport’s Master Plan, but it is also the completion of long term planning that originates back to the 1970s. With an approximate cost of $1.3 billion, Brisbane’s new runway is considered as Australia’s largest aviation construction project to date. This new 3.3km runway is a key piece of infrastructure that will help enable the continued growth of Brisbane as well as becoming one of Australia’s most crucial domestic and international transfer airport. Importantly, this runway will enable Brisbane Airport to meet higher demands of the community it serves, now and for future generations.

With phase two of the runway project beginning in 2016, one critical large scale wind and erosion control project was introduced. This project would later come to provide and cover the foundations for the significant areas of the 360-hectare runway site. Moreover, due to the scale of the project as well as the various earthworks and environmental concerns involved, meticulous planning was required for the project to not only ensure regulations and standard were met, but to also ensure potential health, safety, and environmental risks were realized, managed, and mitigated.

Source: Brisbane Airport Corporation

Learn more about Brisbane airport’s new parallel runway project here.

Challenges

With Brisbane airport partnering with Skyway (a joint venture between CPB Contractors and BMD) for this new parallel runway, various accountabilities were divided between these two organisations. Due to the specific challenges of the project, GRT was contracted by CPB Contractors for this wind and erosion project. Furthermore, the high complexity of this large scale runway project introduced many moderate and heavy vehicles (i.e. trucks, excavators, bulldozers, etc.). These vehicles would operate on the 360-hectare project site which included more than 5,000,000 m3 of earthworks projects. Consequently, these vehicles would introduce severe dust problems that would affect the effective operation of the airport as well as the many workers and vehicles working on site.  These severe dust problems would also be generated in much greater volumes due to the constant operation of vehicles travelling on the project site.

In addition, various environmental challenges were determined to be associated with the runway project as it was located in a sensitive environmental region in Moreton Bay. These environmental challenges would impose specific requirements to GRT for the product supply and application. Furthermore, due to natural environmental constraints like erosion, more than 11 million m3 of sand was required for preloading in various areas of the project site.

As the sand dredging process completed during the first phase of the runway project (2012 to 2015), it was determined that the sand stockpiles in place for preloading have been located on-site for the more than four years. As a consequence, the majority of the sand dredged were determined to have weak structural integrity, making preloading a high potential point of failure during the project’s phase two. To mitigate the potential of preloading failure, surface stabilisation was identified as the corrective action. 

Preloading: the process of loading up poor ground with material to consolidate it.

Since phase two of the $1.3 billion new parallel runway project was estimated to be completed in roughly four years (2016 to 2020), the inclusion of several storm seasons as well as high rainfall events were considered within the design and planning of the project. These potential high rainfall and storm events were considered to cause surface degradation as well as the transportation of unwanted substances into the construction of the runway. If unwanted substances were to be discovered at any point during the project, additional costs and time would indefinitely be utilised to resolve the issue which would consequently increase the total cost of the project. With this in mind, the GRT team was tasked to supply and apply an effective product that would consider all project requirements as well as the challenges and environmental concerns involved.

Solutions

GRT: Enviro-Binder 

Due to the large scale of the project, the GRT team was required to complete an area assessment on the projected runway site to determine the most suitable product/s considering both the environmental and economic impact this product may potentially develop after application. It was determined that the best methodology of controlling erosion was to stop erosion at the source prevent it occurring in the first place. 

Furthermore, environmental constraints and concerns were further considered through the implementation of increased sustainable procedures. As the total estimated required product for the runway project was 320,000 litres, sustainable procedures were accomplished in the form of utilising reusable 23,000-litre bulk bladders for transportation instead of the common 1,000-litre intermediate bulk containers (IBCs). By utilising six reusable bulk bladders for transportation and product containment IBC waste and landfill waste were eliminated. These sustainable procedures helped reduce the associated waste by more than 98%.

The various project requirements and constraints made the unique GRT: Enviro-Binder the recommended product for Brisbane airport’s new parallel runway as it:

• Was a uniquely developed product that followed the ideal of “STOP EROSION AT THE SOURCE – DON’T CATCH SEDIMENT”
• Provided exceptional wind erosion control immediately after application
• Met the strict environmental criteria imposed by the Brisbane Airport and partner companies, CPB Contractors and BMD
• Required minimal maintenance unlike conventional methods
• Allows adaptability for product dilution (between 0.02 and 0.2 litres per square metre) depending on the erosion/dust risk that the area is facing

GRT: Enviro-Binder is a film-forming, polymer emulsion sprayed on or worked into the surface of rail embankment to provide a waterproof, durable, surface that prevents erosion. 

Benefits

The GRT: Enviro-Binder treated runway and associated construction sites delivered high performing results that were expected from the product:

• Reliable management of wind and erosion issues
• Long-lasting erosion control results
• Sustainable – close to zero waste option provided
• Immediately effective upon product application
• Limited the need for sediment fences onsite
• Minimal preparation for the production application
• Waterproof product; not affected by high rainfall or storm seasons
• Cost-effective results