Advanced liquefaction mitigation for critical infrastructure
Soil liquefaction occurs when loosely packed, water-saturated sands or silts experience rapid cyclic loading that increases pore-water pressure until the soil behaves like a fluid. The consequences—tilting structures, cracked pavements, damaged utilities—are catastrophic for any asset built on susceptible ground.
Traditional liquefaction mitigation methods (e.g., stone columns, deep soil mixing, vibro-compaction) often require large, heavy equipment and are best applied before construction. Retrofitting existing sites—particularly beneath buildings, pavements, or critical assets—can be extremely disruptive, time-consuming, and expensive. Many conventional solutions are not feasible where access is restricted, structures are already in place, or downtime must be minimised.
Soil liquefaction occurs when loosely packed, water-saturated sands or silts experience rapid cyclic loading that increases pore-water pressure until the soil behaves like a fluid. The consequences—tilting structures, cracked pavements, damaged utilities—are catastrophic for any asset built on susceptible ground.
Geobear liquefaction mitigation
provide a targeted, low-impact alternative. By injecting an expanding geopolymer beneath or within liquefiable strata, the process simultaneously compacts the soil skeleton and creates inter-particle bonding that limits excess pore-pressure generation.
Applicable to
- Critical facilities and lifelines – power stations, substations, pipelines.
- Transport corridors – rail embankments, bridge approaches, airport aprons.
- Waterfront structures – quays, seawalls, reclaimed land.
- Industrial and residential foundations in seismic zones.
Key effects
- Increases relative density (Dr) by 10–25 %.
- Raises shear-wave velocity (Vs) and cyclic resistance ratio (CRR), cutting liquefaction potential.
- Forms drainage barriers that slow pore-pressure rise during seismic shaking.
Targeted injection
mall steel tubes (12–16 mm) are installed to reach liquefiable layers, typically 3–10 m bgl.
Controlled expansion
The injected geopolymer expands gently, compacting saturated sand and forming low-permeability reinforcement bulbs.
Rapid stabilisation
Within minutes the material hardens, creating a composite matrix of soil + geopolymer with higher stiffness, lower compressibility, and reduced drainage path length.
Design and Verification
Design follows Eurocode 7 (EN 1997-1) for ground improvement and Eurocode 8 (EN 1998) seismic requirements. Analytical modelling and site-specific testing ensure that treated soils achieve the targeted Factor of Safety against Liquefaction > 1.3.
|
Parameter |
Typical Improvement |
Verification Method |
|
Relative density (Dr) |
+15 – 25 % |
CPT / SPT correlation |
|
Undrained shear strength (Cu) |
+100 – 200 % |
Vane / CPTu tests |
|
Shear-wave velocity (Vs) |
+30 – 50 % |
MASW / cross-hole seismic |
|
Cyclic resistance ratio (CRR) |
Up to 1.8 × initial value |
Simplified Seed–Idriss method |
|
Post-event settlement reduction |
60–80 % |
FEM / empirical models |
Field and centrifuge studies show that geopolymer-treated zones maintain effective stress even after hundreds of load cycles, preserving bearing capacity where untreated soils liquefy.
Case evidence and research highlights
Laboratory triaxial tests
on geopolymer-stabilised sands show pore-pressure generation < 25 % of untreated samples after 20 cycles.
Centrifuge modelling
indicates treated ground maintains > 80 % of pre-loading stiffness post-shaking.
Field monitoring in Asia and Europe and USA
demonstrates permanent density increase and no liquefaction during moderate seismic events.Key advantages for contractors and asset managers
Choosing the Geobear solution provides a distinct set of advantages for projects on liquefaction-prone sites, directly addressing the limitations of older techniques.; they include:
Minimal site disruption
Our process is carried out using small, mobile equipment. There is no need for major excavation, spoil removal, or large piling rigs, allowing other site operations to continue uninterrupted.
Speed of treatment:
The geopolymer cures to 90% of its full strength in just 15 minutes. This allows for rapid treatment of large areas, compressing project schedules by up to 70% compared to traditional methods.
Ideal for difficult access & existing assets
Our ability to operate with a small footprint makes our solution perfect for retrofitting existing structures, working inside buildings, or on sites with restricted access where heavy machinery cannot go.
Lightweight, high-strength material
The injected geopolymer is incredibly strong yet lightweight. This strengthens the ground without adding significant overburden, a critical consideration when treating weak underlying soils.
Verified performance
The improvement is immediate and can be verified in real-time with post-treatment CPT testing, providing engineers and clients with complete confidence and a clear audit trail of the works.
Sustainable & environmentally inert
The Geobear solution requires less energy and material transport than traditional methods. The cured geopolymer is environmentally neutral and does not leach chemicals into the ground.
Partner with Geobear on your next project
Our in-house engineering team works collaboratively with primary contractors and consulting engineers to design bespoke, value-engineered solutions for liquefaction mitigation
