Challenge: Rail Embankment Investigation for Stability and Monitoring
GeoEnviro Solutions Ltd (GES) was commissioned to carry out a detailed rail embankment investigation along an active freight branch line. The objective was to assess slope stability and monitor potential groundwater conditions through a combination of borehole drilling, in-situ testing, and long-term piezometer monitoring.
The scope involved the drilling of 23 boreholes across five targeted cross sections to determine the engineering characteristics of cohesive and granular materials within the embankment. The works needed to be carried out without disrupting ongoing freight operations, while also overcoming difficult access and challenging site terrain.
Key project constraints included:
- Long-Term Monitoring Requirements: Piezometers needed to be installed to record groundwater variations over a 12-month monitoring period.
- Live Freight Operations: All works were undertaken during midweek day shifts while freight services continued, requiring strict adherence to operational safety and efficient time management.
- Access on Steep and Vegetated Slopes: Many borehole locations were positioned on challenging gradients with limited direct access.
Solution: Adaptive Investigation with Lightweight Access and Modular Drilling Equipment
GES implemented a safe, efficient, and flexible approach to overcome logistical and operational challenges:
- Lightweight Access Solutions: Aluminium staircase sections were installed to create safe and secure access to each borehole location.
- Modular Window Sample Rigs: Two lightweight modular drilling rigs were used, allowing them to be dismantled and hand-carried between borehole positions and across different investigation sections.
- Comprehensive Sampling and Testing:
- Undisturbed samples of cohesive clay were obtained using U70 steel tubes for high-quality laboratory testing.
- Standard Penetration Tests (SPT) and Hand Shear Vane tests were carried out on-site to provide immediate strength and density data.
- In-situ sand replacement tests and laboratory Shear Box testing will provide further data on the granular material properties of the embankment.
- Piezometer Installations: Three investigation sections included piezometers installed at varying depths to monitor for any perched water within the embankment, enabling seasonal trend analysis over the next year.
Result: Ahead-of-Schedule Completion with Reliable Geotechnical Data
The investigation was completed earlier than programmed, without any incidents, and in full compliance with railway safety requirements. Outcomes included:
- Uninterrupted Freight Operations: Works were planned to ensure no interference with live rail traffic.
- Comprehensive Data Collection: The combined in-situ and laboratory test results will provide robust data to support future maintenance or remedial works.
- Responsible Site Handover: All work areas were left tidy, safe, and free from waste, maintaining GES’s commitment to environmental and operational best practices.
With extensive experience in railway ground investigations, embankment stability assessments, and long-term groundwater monitoring, GeoEnviro Solutions Ltd continues to deliver precision, safety, and quality in complex rail environments.
Looking for rail infrastructure ground investigation specialists?
Contact us for professional in-situ testing, ground investigation, and monitoring services tailored to the rail sector. Interested in more rail-related case studies? Read our case study about Precision Ground Investigation at Malvern Rail Link.
Works were carried out in full compliance with rail safety guidelines issued by Network Rail, ensuring zero disruption to ongoing freight operations.
