Ground Developments Ltd (GDL) is involved in a project to develop land at Hillside Halls, Yarrow Terrace, in the city and their deep soil mixing is providing a solution to challenging ground conditions being experienced on the site. The site was formerly a quarry, and remediation is needed to the land of depths around 17 metres.

Andrew Warneford, projects director for GDL, said: “The former quarry at Hillside Halls was backfilled in the 1950s in an uncontrolled manner. This presented a significant issue for the proposed development because these soils were likely to settle significantly when a load was imposed by the new housing, roads and sewers.

“Naturally, excess settlement below the proposed structures is unacceptable to the client, their engineer and statutory bodies. Our designed solution to improve the formation by means of deep soil mixing delivers an increased soil bearing pressure and eliminates the potential for excess settlement.”

Following the improvement of the formation soils with the deep soil mixing technique, GDL is using its soil stabilisation and earthworks solution to upfill the site to design levels, which will provide a structural earthworks platform to allow for a nominal depth, standard stiffened foundation.

GDL’s deep soil mixing technique is fully tested, and delivers uniform ground improvement and a sound design platform. In addition, it is a cost-effective alternative to traditional piling techniques.

Kevin Mackenzie commercial director, added: “The specialist apparatus that we operate means that we have the capability to deliver cost-effective solutions for the difficult soil conditions that we often come across in Scotland.

“We are the only company in Scotland which has the resources and expertise to provide specialist deep soil mixing solutions. Indeed we are one of only a couple of companies with this expertise in the UK. This project aligns with our business ethos of being the enabling contractor of choice for difficult and challenging sites.

“We have deployed our deep soil mixing techniques for a number of our clients, but this is one of our largest projects to date. In the coming year we intend to actively pursue other applications for the use of this specialist technique, specifically on projects with poor formation at depth and were strict settlement criteria needs to be met.”