Foundation design and construction for store in Zagreb, Croatia

Construction of a new Ikea store in Zagreb, Croatia required a foundation solution to address the poor ground conditions on site, including the risk posed by seismic events, as well as meeting the strict limits on differential movement. This paper describes how adoption of a displacement pile technique avoided generating large volumes of spoil that would otherwise require disposal, easing logistics at the site. The technique also avoided pile bore instability in the poor ground conditions with high groundwater levels. Provision of instrumentation on the piling rig, recording a range of parameters during pile installation, provided an effective control on the acceptability of each working pile constructed. By completing a number of test piles prior to the main piling works, which were also undertaken by the instrumented rigs, site-specific limits on the rig-recorded parameters were determined, enabling a check on the acceptability of each pile constructed.