A time-critical ground improvement challenge at a major power generation station in Ireland was successfully resolved using geopolymer injection technology, avoiding conventional excavation works and keeping a complex heavy-lift programme on schedule.
The challenge
A major Irish power station required the construction of a reinforced concrete pad to support a steel mat carrying a load of approximately 350 tonnes. The pad needed to be installed within a tight two-to-three-week programme window.
Site investigations confirmed that the underlying ground consisted of weak, poorly compacted sand fill overlying soft peat. In its existing condition, the ground was incapable of supporting the proposed loads without significant settlement.
Traditional solutions such as piling or cement grouting were considered impractical due to programme constraints. In addition, the operational requirements of an active power station ruled out solutions involving extensive excavation or prolonged site occupation.
Geobear was engaged to improve the ground conditions beneath the proposed pad location, enabling the heavy lift to proceed safely and on programme.
The engineering approach
The project presented an additional challenge. CAT scanning identified the potential presence of buried electrical services, restricting the use of deep intrusive drilling techniques.
To accommodate this constraint, Geobear's engineers revised the treatment design. Rather than targeting the full soil profile, the solution focused treatment within the upper 2.5 metres of the ground.
A specialist geopolymer formulation with an extended cream time was selected to allow greater penetration and distribution within the loose sand fill. The objective was to densify and consolidate the fill material, creating a stiffer load-distribution layer while reducing stress transfer to the underlying peat.
The works were completed over a single weekend using a two-person crew and compact equipment. No excavation, spoil removal or disruption to ongoing power station operations was required.
The results
Post-treatment testing confirmed a substantial increase in ground resistance across the treated area, with measured values indicating more than a twenty-fold improvement compared with pre-treatment conditions.
Equivalent shear strength assessments demonstrated that the required bearing capacity had been achieved consistently throughout the treatment zone.
The concrete pad was installed on schedule, the heavy-lift operation proceeded as planned, and the 350-tonne load was successfully positioned within the project programme. No settlement issues were reported during or after the lifting operation.
Wider applications across power and heavy infrastructure
Although this project focused on a temporary heavy-lift platform, geopolymer injection can be applied across a wide range of power generation and critical infrastructure assets, including:
- Substation and switchgear foundations, where settlement can affect sensitive electrical infrastructure;
- Turbine and generator plinths requiring increased bearing capacity beneath heavily loaded assets;
- Access roads and hardstandings used by heavy construction and maintenance equipment;
- Slab and raft foundations that require re-levelling beneath operational facilities;
- Void filling beneath structures, culverts and ground-bearing slabs affected by erosion, settlement or service migration.
Compared with many traditional foundation solutions, geopolymer injection can also offer significant carbon savings while reducing disruption, programme duration and site footprint.
For asset owners and contractors managing programme-critical projects in operational environments, geopolymer injection provides a fast, low-disruption and technically robust alternative where conventional methods may be impractical.
Delivered by Geobear Ireland | www.geobear.com | richard.dee@geobear.com