Groundforce props at Chatham: design, monitoring and risk notes for basement works
Reviewed by Joe Ashwell
First reported on The Construction Index
30 Second Briefing
Groundforce Shorco modular hydraulic props are being used by Lashi Contractors to support a 35m by 46m, up to 6m-deep basement excavation for a 61-apartment development for Callisto Homes in Chatham, formed within a secant-piled wall and concrete capping beam. To deal with the sloping site and stepped capping beam, Groundforce dispensed with a waling beam and instead cast corbels into the capping beam, installing six knee-braced MP50, MP150 and MP250 props, including 23m-long MP250s with 813mm-diameter tubes. With a Victorian property on shallow foundations immediately adjacent, three braces carry Senceive wireless load monitoring via 3G gateway, providing continuous load data and SMS alerts if preset thresholds are exceeded.
Technical Brief
- Corbels cast into the capping beam remove the need for a perimeter waling beam.
- Knee-braced configuration concentrates support in corners, reducing clashes with permanent works and ground floor slab.
- MP250 props use 813 mm-diameter tubes to control deflection and buckling over their 23 m length.
- Temporary works design was jointly developed by Groundforce Shorco, Lashi Contractors and the client’s temporary works designer.
- Senceive wireless load cells in prop pins stream continuous force data via a 3G gateway to remote monitoring.
- SMS alerts trigger when prop loads exceed pre-set thresholds, enabling rapid response before movements affect the Victorian property.
- Adjacent Victorian structure on shallow foundations drove stringent stability criteria and continuous load surveillance on three braces.
Our Take
Groundforce Shorco’s use of long-span MP250 props here echoes its work on the deeper 30 Marsh Wall and Clore Manor basements, signalling that its modular hydraulic systems are becoming a default choice for complex urban excavations in the UK rather than just flagship London jobs.
With only six props covering a roughly 35m by 46m, up-to-6m-deep box, the design leans heavily on high-capacity members, which typically reduces on-site congestion and speeds follow-on trades compared with denser, lower-capacity propping layouts seen in some other basement schemes in our database.
The wireless monitoring on three knee-braces adjacent to a neighbouring building aligns with Groundforce Shorco’s recent safety-focused tooling (such as SheetMaster 2.0), and suggests that live load data is now being treated as a standard risk-control measure on constrained residential sites rather than a specialist add-on.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
Related Articles
Related Industries & Products
Construction
Quality control software for construction companies with material testing, batch tracking, and compliance management.
Mining
Geotechnical software solutions for mining operations including CMRR analysis, hydrogeological testing, and data management.
CMRR-io
Streamline coal mine roof stability assessments with our cloud-based CMRR software featuring automated calculations, multi-scenario analysis, and collaborative workflows.
HYDROGEO-io
Comprehensive hydrogeological testing platform for managing, analysing, and reporting on packer tests, lugeon values, and hydraulic conductivity assessments.
GEODB-io
Centralised geotechnical data management solution for storing, accessing, and analysing all your site investigation and material testing data.