CASE STUDY: DRILLING and GROUTING, GLASGOW ZOO
Project: Artificial consolidation of a redundant mineral tunnel
Location: Glasgow
Client: Miller Homes, Scotland
Project Overview
A large-scale, phased housing development was planned for a site in Glasgow. The ground needed stabilising before any of the development's ground works could begin.
A redundant mineral tunnel, measuring some 3m x 3m had to be consolidated. The depth was 20m from ground level and the length of the tunnel section was 200m from the opening.
Our approach was to probe drill to understand the tunnel cavity in more detail. How deep was it? Was it filled at all? We then used these same drill holes to inject our fluid grout.
In order for the tunnel to remain stable and to ensure the grout didn't just 'leak' away we had to use some new methods. We put a stopping stone wall into the tunnel using a mixture of grout and gravel to effectively seal it off to the desired length. Once this was in place we then injected 3,000 tonnes of mixed fluid grout into the cavity.
The drilling and grouting techniques used have ensured that the artificial consolidation has been successful and so further works on site can go ahead. We were on site, as per the programme, for five weeks.
We injected approx 3,000 tonnes of a mixed fluid PFA and OPC grout
Rig: Soilmec 401
