The EGIP consortium, comprising Babcock, Morgan Sindall and Costain, is responsible for upgrading the railway system between Edinburgh and Glasgow. Part of this work is the installation of overhead electric power gantries through the Glasgow’s Queen Street Station tunnel so that standard electric trains can run along the whole line. Currently, the tunnel is not tall enough, so the floor of the tunnel needs excavating to make it deeper. Structural Soils was tasked with carrying out the site investigation work to ensure so that when this is done there will be no problems with groundwater or lack of wall support.
Structural Soils director, Jon Bassett, explains, “We had been planning hard for this project since early December. There are so many logistics that you need to think about.
“For 34 hours back to back, we drilled boreholes in the floor of the tunnel and core holes though the roof and walls. We also installed remote groundwater monitoring equipment (vibrating wire piezometers). Everything, including the drilling rig, had to be moved to each location on rails and lifted on and off each time we drilled a borehole.”