Summary
We were contacted to protect 38 homes situated within a large residential housing estate in South Glasgow, constructed across a former limestone quarry. The properties were identified by the engineers as showing cracking/distortion in excess of 15 mm due to house subsidence. Geobear were contacted to provide a solution to the problem that would stabilise the ground beneath the houses and result in minimal disturbance to the residents.
Objectives
In total over 900 linear metres of walling (both internal and external) required treatment, which required ground stabilisation to a depth of 4.00 m. Pre and post treatment dynamic penetrometer testing was to be completed at 5.00 m intervals along all the walls, with the on-site engineer signing off properties when an increase in bearing capacity of the treated soils had been achieved. The ground conditions encountered were made ground/in-filled materials to in excess of 20 m below ground level.
Technology Applied
The ground stablisation was achieved by injecting geopolymers into the shallow soils which would also improve the bearing capacity. The work took 16 weeks to complete all 38 houses and the tenants could stay in their homes throughout the process.
Outcome
All post-treatment dynamic cone penetrometer tests recorded an increase in bearing capacity allowing all properties to be signed off as completed within the 16 week deadline. The client chose to use the Geobear systems due to the minimal disruption for the elderly residents that would be caused by our works, along with the speed at which the properties could be successfully treated.
