Background

BAM Ritchies were appointed to carry out a ground investigation at Waller’s Ash Cutting in Hampshire to inform the design and renewal of the rock cuttings on the approach to, and beyond, Waller’s Ash Tunnel.

The scope of work included geological mapping and a geomorphological survey to characterise the site’s complex chalk geology. GeoAccess were engaged by BAM Ritchies to complete this aspect of the works, using rope access expertise to capture detailed on-site geological observations that would be critical to design development.

Method

A two-person rope access geotechnical team was deployed, comprising an IRATA-trained Geotechnical Engineer and a Level 3 Supervisor.

Over three days, the team completed mapping at seven drop locations on both the high-mile and low-mile sides of the tunnel. Rope access techniques allowed safe and direct examination of exposed slopes, enabling in-situ descriptions and detailed geological logging.

The site geology consisted of Superficial Deposits overlying the Newhaven Chalk Formation. Chalk exposures were described in accordance with CIRIA C574 (Page 94), while drift materials were logged following BS5930:2015+A1:2020. Data collected in the field was then compiled and developed into a detailed rock cutting examination report.

Innovations & Solutions

GeoAccess used rope access techniques to safely inspect vertical and overhanging chalk cuttings that would otherwise have been inaccessible. This approach enabled cost-effective, rapid, and high-resolution data collection for BAM Ritchies without the need for scaffold or heavy plant equipment.

Results & Conclusion

The inspection enabled accurate geological characterisation of Waller’s Ash Cutting, supporting BAM Ritchies in developing a robust renewal design.

GeoAccess’ experienced rope access engineers combined field expertise with previous examination records to improve site efficiency and reporting accuracy.

This project highlights GeoAccess’ position as a trusted partner in geotechnical mapping, slope stability assessment, and rock cutting inspections for major UK infrastructure renewal schemes.