Ground Improvement at Heathrow Airport

Introduction

Heathrow Airport is one of the busiest airports in the world, serving millions of passengers every year. In 2022, Geobear was commissioned to provide a ground improvement solution at Terminal 3 (T3) of the airport, with the objective of facilitating a vertical expansion that would have otherwise required a time-consuming concrete reconstruction beneath foundation pads. The traditional method would have taken up to two months to complete, but Geobear’s innovative solution was four times faster, taking only two weeks to complete.

Satellite view of airport

Location of site

Challenges

The project presented a number of challenges, including the need to carry out the work in a live airport environment without disrupting airport operations or affecting passenger safety. The Geobear team also had to contend with the presence of buried services and other utilities, which required careful planning and execution.

Solution

Geobear’s in-house design team used PLAXIS to accurately model and design a solution that met the client’s requirements. The team used geopolymer injection to increase the load-bearing capacity of the foundation pads, without the need for excavation. This approach was not only faster but also more sustainable, as it eliminated the need for the disposal of excavated material.

Plaxis design solution

Results

Injection tubes in place

Cored holes with injection tubes inserted

The project was completed successfully within the client’s specified timeframe and budget, and with no disruption to airport operations. Geobear’s solution increased the load-bearing capacity of the foundation pads by up to 70%, providing a solid base for the vertical expansion of the terminal. The use of geopolymer injection also had significant sustainability benefits, reducing the project’s carbon footprint by up to 60%.

Conclusion

Geobear’s innovative ground improvement solution at Heathrow T3 demonstrated the company’s commitment to sustainability, innovation, and excellence in design. The project not only delivered outstanding results for the client but also contributed to the reduction of the project’s environmental impact. The success of the project has further strengthened Geobear’s reputation as a leading provider of ground engineering solutions in the UK and beyond.

Client Testimonial

Our project greatly benefited from the professional geotechnical design and execution services provided by Geobear.  As structural engineers on this vertical expansion project, the building’s existing foundations needed strengthening.  We had initially proposed to increase the area of the existing concrete pad foundations – which was going to be a costly and challenging construction.  After consultations with Geobear’s geotechnical designers and reviewing the existing ground conditions with them, we were able to use one of their innovative solutions – inject grout polymer beneath the existing foundations to support the expansion.  This was a huge success to the project saving cost, time and was more sustainable.  Geobear also monitored the building’s movement and assisted the contractor during grouting to eliminate execution error and advise on the extent of grout required.  The end results were very impressive and successful. Throughout the design and construction process Geobear was a pleasure to work with.  We would highly recommend them and would like to see their innovative, less invasive solutions used more often.

Steve Pinnegar, C&S Director, BakerHicks

To learn more about the technical requirements and solution please contact Geobear Technical Director Dr Mohamed Wehbi – [email protected]