Residential Subsidence

Ground Stabilisation, Belfast

Challenge

Severe ground movement caused structural damage, requiring temporary structural support and tenant relocation.

Solution

Geopolymer injection to 2.1m depth stabilised soils and improved bearing capacity without excavation.

2 days

Full stabilisation completed on site

57% increase

Average soil bearing capacity improvement

2.1 metres

Targeted treatment depth achieved

Background

A property in Belfast, owned by a housing authority, experienced significant ground movement beneath the structure. This resulted in visible cracking and progressive structural damage, ultimately requiring the building to be temporarily supported using structural steelwork.

Due to the severity of the movement, the tenant had already been relocated to alternative accommodation prior to remediation works commencing. In many similar cases, however, this step introduces substantial cost, logistical complexity, and disruption for housing providers.

The project presented an opportunity to not only stabilise the structure, but also demonstrate a more efficient and less disruptive alternative to traditional underpinning methods.

Challenge

Technical Challenges

  • Ongoing ground movement impacting structural integrity
  • Requirement to stabilise without further disturbing weakened soils
  • Property already in a compromised condition requiring careful intervention
  • Need to validate improvement in load-bearing capacity post-treatment
  • Social housing context requiring cost and programme efficiency

Solution

Geobear delivered a targeted ground improvement solution using engineered geopolymer resin injection.

Injection tubes were installed externally and internally around the affected structure, allowing precise delivery of geopolymer resin into the underlying soils. The material expanded within the ground, filling voids, compacting weak zones, and increasing overall soil stiffness.

Treatment was carried out to depths of up to 2.1 metres, targeting the active zone of movement beneath the foundation. The process was fully controlled and monitored in real time to ensure uniform improvement and avoid overstressing the structure.

All works were completed using compact equipment, eliminating the need for excavation, heavy machinery, or large-scale site setup.

 

Verification & Performance

Pre- and post-treatment testing was undertaken to quantify the effectiveness of the solution.

Results confirmed:

  • Average increase in soil bearing capacity of approximately 57%
  • Measurable improvement in ground stiffness and load distribution
  • Stabilisation of the structure, addressing the root cause of movement

These outcomes provide confidence that the underlying ground conditions have been successfully improved and that further structural movement risk has been mitigated.

Results

 

Before

wall crack

After

boyd 1

 

Programme & Delivery

The entire stabilisation programme was completed in just two days on site.

This rapid delivery significantly reduced the overall project timeline compared to traditional underpinning, which would typically involve:

  • Excavation in phases
  • Extended curing periods
  • Prolonged structural support requirements

The speed of delivery enables faster progression towards reinstatement and reoccupation.


Social Housing Impact

While the tenant had already been relocated in this instance, the project clearly demonstrates a key advantage of geopolymer injection for housing providers.

In many comparable scenarios, Geobear’s non-invasive approach allows:

  • Tenants to remain in their homes during works
  • Elimination of decanting and temporary accommodation costs
  • Reduced administrative and logistical burden
  • Minimal disruption to residents and neighbouring properties

For organisations such as NIHE, this represents a significant operational and financial benefit.


Carbon & Sustainability

Geobear’s solution avoided the need for mass concrete underpinning and excavation-intensive works.

Key sustainability benefits include:

  • Reduced material usage compared to traditional methods
  • Elimination of spoil removal and associated transport emissions
  • Lower overall carbon footprint through rapid, targeted intervention
  • Minimal site disturbance and reduced environmental impact

Outcome

The property has been successfully stabilised, with improved ground conditions verified through testing and the risk of further movement mitigated.

The works are supported by a 10-year guarantee, providing long-term assurance to the client. With stabilisation complete, the property can now progress towards reinstatement and return to service significantly faster than would have been possible using conventional repair methods.

Let’s talk about your home

Every home is unique. Our experts are ready to listen and provide answers tailored to your specific property and concerns.

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