Geotechnical design challenges associated with construction of the new AMCOR paper mill in Botany, NSW

The new Amcor B9 paper mill in Botany, NSW, involved the design and construction of pile and slab foundations, temporary and permanent retaining structures, deep excavations, dewatering and ground improvement. There were numerous technical and design challenges, including tight settlement tolerances, significant cyclic loads, adjacent heritage structures and uncontrolled fill material. Construction staging meant that settlement sensitive infrastructure was constructed simultaneously with and adjacent to dewatering, excavation and dynamic ground improvement activities. Geotechnical design included the derivation of realistic and workable soil parameters from a combination of laboratory testing and insitu soil testing. Analysis and design was carried out using a combination of empirical calculations, slope stability, settlement and finite element software, while movement monitoring was carried out to compare predicted and actual displacements.