A soil reinforcement project in the Port of Tilbury in Essex, supplied by Burdens, a leading distributor of underground drainage and civil engineering materials, has been completed in a record time of two weeks.
A 1m thick cellular foundation mattress solution was created by Tensar International which specialises in ground stabilisation and soil reinforcement, in order to strengthen part of the Port’s foundations. Due to its long-standing relationship with Tensar and understanding of ground engineering, Burdens was able to supply the materials in time for the berth to be quickly re-opened.
Burdens offers expertise, as well as choice, on the latest solutions needed for ground stabilisation and soil reinforcement whilst also holding the largest distribution stocks in the UK of geotextiles and geogrids, with a selection of up to 10,000 rolls. After it won the Port of Tilbury project, Tensar approached Burdens for its technical and design guidance on the most suitable geotechnical materials.
The Port of Tilbury is located on the River Thames and is the principal port for London. It handles a variety of bulk cargo, timber, cars, and container traffic and remains and is also the main UK port for handling the importation of paper.
Earlier in the year, the soil foundations of Berth No 1, which was used for the storage of aggregates, had been overloaded and failed. The owner needed to get the berth reopened as soon as possible and therefore commissioned consultant Haydn Evans to design a stable, practical and cost effective solution over the soils.
The main contractor, Tamdown Group installed the mattress which was fabricated on site using Tensar’s Uniaxial and Triax® Geogrids. These geogrids are backed by over three decades of technical research and experience, and have been utilised around the globe. The geogrid mattress was filled with 6F2 granular capping fill, which results in a very stiff layer able to mobilise more bearing capacity from the foundation soils compared to simple horizontal soil reinforcement layers. It also helps control differential settlement, increasing bearing capacity. By partnering with Burdens on the project, Tensar was confident that the materials used were to the highest of industry standards, reinforcing the quality of its unique solution.
The Geogrid solution has a design life of 120 years. Alan Long, Trading Director, Burdens, said: "As land usage becomes increasingly critical, there is a requirement for higher geotechnical standards and we can assist speciﬁers in joining up the disparate elements of a geotechnical solution which adheres to such standards. When we were asked to support the project we were willing to do everything we could to get such an integral London port back in operation. We’re proud to have been involved in such a successful venture."
Due to the nature of the project Haydn Evans consulted Tensar, world leaders in soil reinforcement and ground stabilisation to come up with a geosynthetic based solution which resulted in the foundation mattress. The mattress was fabricated on site using Tensar’s simple polymer jointing rods (bodkins) creating stable diamond shaped cells over a footprint of approximately 60 by 63 metres. Finally a High Vis layer was placed just over the filled mattress and below a final granular capping layer in order to warn against any future excavation of the structure below.
John Dixon, Tensar’s Area Civil Engineer explains: "Working with weak or variable ground usually presents considerable challenges for the contractor in many construction projects. However, our use of technology and industry knowledge in ground stabilisation aims to improve performance as well as providing significant cost and environmental savings too. Due to the nature of the soft alluvial soils by the River Thames, which in this case also had only residual strength due to pre-shearing, we had to deal with challenging soil parameters, which made it a complicated and interesting project to respond to. It was the collaboration of a group of experienced and professional companies, including Burdens which enabled it to be fulfilled to such a tight timeframe."
Burdens is a leading distributor of underground drainage and civil engineering materials with more than 80 years of experience servicing the industry. It maintains its leading position through its national network of branches, providing stock in depth and utilising specialist delivery and handling equipment.