Methodology
The construction methodology of the combi-wall piles was unusual due to restricted impact driving and the presence of a hard caltite layer within the underlying strata. Oversized holes were drilled, the tubes forming the combi-wall dropped into the bores and the annulus between the bore and the tube filled with sand. This led to difficulties analysing the combi-wall, particularly assessing the level of movement of the wall once the dock was dewatered.