Overview 

Mainmark was engaged by CML to deliver specialist ground improvement works as part of the refurbishment of platforms 3 and 4 at Tottenham Hale station, a key north‑east London transport hub, providing interchange between National Rail (Greater Anglia and Stansted Express) and the Victoria line.

Working within tight possession windows, Mainmark deployed its Teretek® engineered resin injection solution to improve ground conditions beneath 77 new foundation locations, supporting the installation of GRP platform structures.

Challenge

The project required ground improvement to achieve a minimum bearing capacity of 75kPa beneath newly installed platform foundations. Key challenges:

• Treatment across 77 discrete foundation pads with consistent performance criteria

• Delivery within restricted rail possession over a bank holiday blockade

• Coordination with multiple contractors delivering concurrent works

• Requirement for post-treatment validation of soil strength

Solution 

Teretek® engineered resin injection system, designed for precision ground improvement in constrained rail environments, included an injection grid spaced at 1–2 m centres across each foundation footprint, with treatment extending to 2 m below formation level.

Small-diameter holes (16–20 mm) were drilled using handheld equipment. Injection tubes installed to deliver resin at controlled depths.

Ground improvement achieved through controlled permeation into granular soils, compaction via volumetric expansion, and void filling along weak zones.

Monitoring and Validation

• Monitoring and control: Real-time laser level monitoring (±0.5 mm) was used, with uplift controlled to 1–3 mm per location and digital QA/QC capturing injection volume, flow rate, and depth.

• Validation testing: DCP testing (Pagani DPM30, 30 kg hammer) was carried out at 100 mm intervals on 10% of foundations, with pre- and post-injection results confirming improvement.

The fast-reacting resin enabled consistent delivery, with parameters adjusted to maintain control and performance.

Outcome

Works were completed within planned possession windows, delivering improved soil strength and bearing capacity, enhanced ground conditions across all 77 pads, and controlled, verifiable densification, with no excavation required.

Raj Sharma, Contracts Manager at CML says:

'Mainmark provided a highly professional and technically capable service throughout the works at Tottenham Hale Station. Their design input, engineering expertise, and proactive weekend support were key to delivering a practical, cost-effective solution without compromising quality or programme'

Rail Sector Value

• Delivery in short-duration blockade windows

• Minimal working footprint (<150m² operational zone)

• Non-intrusive methodology eliminating need for excavation

• High level of process control / data transparency

• Reduced coordination risk with parallel trades

Sustainability and  Asset Performance

• No spoil generation or material disposal

• Reduced plant usage and associated emissions

• Lower embodied carbon compared to traditional dig-and-replace methods

• Improved long-term ground performance

• 50-year material durability warranty supporting asset lifecycle extension

Planning a rail infrastructure project?

Talk to our team about how our ground strengthening solutions can help reduce risk, improve programme certainty, and deliver long-term performance. Call 0800 975 0507