Chevrons Wheatstone Project is one of Australia’s largest resource projects. It will include an onshore facility located at Ashburton North Strategic Industrial Area, 12km west of Onslow in Western Australia’s Pilbara region.
The project aims to extract Liquid Natural Gas (LNG) from the Wheatstone and surrounding gas fields approximately 200km north of the build site at Onslow.
The multi-billion dollar project is currently under construction with Bechtel as the lead design and build contractor.
During the initial geotechnical investigation, a potential liquefiable layer of soil (Unit 2b) was identified below the proposed LNG Tanks site.
The purpose of the trial was to assess if driving closed and open ended steel tube piles and inclusions through this layer would provide sufficient densification of Unit 2b to mitigate the potential for liquefaction to occur during a seismic event.
CMW Geosciences (CMW) scope of work included driveability assessments, a crane pad stability assessment and QA/QC monitoring of the pile driving trial.
The QA/QC monitoring involved a CMW representative being on site for the duration of the piling and testing programme to record and review driving characteristics. CMW was also responsible for directing and managing CPTu and pore pressure dissipation testing prior to, during and at the completion of the piling works.
The trial was completed well within the nominated timeframe and achieved the desired outcome whereby the CPTu and dissipation records indicated that the potential for liquefaction of Unit 2b had been effectively mitigated.