Project Overview
Moore Construction delivered piling and retaining works for the Mitre 10 Timaru expansion, supporting the development of new retail and garden centre facilities.
The project required the formation of a large excavation platform to enable construction, with ground conditions comprising deep loess soils overlying basalt and historic gravels.
Engineering Solution
A continuous bored pile retaining wall was selected to provide stability for excavation works, while maintaining integrity of the surrounding ground and adjacent structures.
The system incorporated drilled piles tied together with reinforced concrete capping beams and shotcrete infill panels to create a continuous structural wall.
Piling Works
The project involved the installation of 116 bored piles with diameters ranging from 750mm to 900mm and depths between 6 and 12.5 metres.
- Drilling using Geax EK110 piling rig
- Tremie concrete placement for all piles
- Reinforcement cage installation into each pile
A test pile was completed early in the programme to confirm ground conditions and validate construction methodology prior to full production works.
Construction Methodology
Piles were installed in a hit-and-miss sequence to maintain stability of the surrounding ground mass and manage interaction between adjacent piles during construction.
Excavation & Site Development
The retaining system enabled excavation of approximately 6.5 metres in depth in key areas of the site, facilitating the expansion of the building footprint and development of the new structure.
