The design and specification of foundations, earthworks, retaining structures or reinforced slopes requires a strong background in Civil Engineering and Engineering Geology to ensure the best solution is established for each project considering the Conceptual Ground Model and the proposed development. This allows the formulation of efficient, cost effective and robust design advice for clients, design engineers and construction teams.
ESP consistently work in a wide range of complex geological and hydrogeological environments, and our sound investigation methodologies and extensive experience allows a detailed understanding of how the ground will behave in response to varying project specific development designs. This includes areas where anthropogenic influence (e.g. coal mining, docklands, former metal processing works etc.) has resulted in spatially variable ground models and geotechnical hazards.
Our team includes Chartered Engineers and Geologists who are experts in providing traditional and alternative foundations solutions including those where challenging conditions require ground improvement techniques (including the stabilisation of mine workings). Our projects have included raft foundations on low strength ground, ground treatment, deep basements and piled foundations.
For road/rail projects, ESP have developed and checked the long-term stability of proposed designs or prescribed remedial measures for failing existing structures in accordance with British and European standards (including EC7). We have also specified earthworks to achieve required structure performance and this has included the re-use of site won materials.
Specification of retaining walls and reinforcement/stabilisation measures for soil/rock cuttings and embankments has enabled developments by mitigating long term stability risks and achieving/improving any spatial requirements.
Examples of ESP Geotechnical Engineering experience includes:
- Remediation of failed road cutting at Stembridge and in Swansea;
- Earthworks specification for highway improvements in Worcestershire;
- Geotechnical Design Closure Report for large cutting in fold complex and large embankment over low strength peat and clays with shallow groundwater in Cross Hands;
- Geotechnical Design Report for numerous schemes in Wales and England for Highways;
- Geotechnical Design Report including pile design in thick low strength Wind Blown Sands and glacial soils for proposed Swansea University Development;
- Surcharging and band drain design at Weston Super Mare and Barry;
- Plot specific foundations designs for a housing development across spatially variable ground conditions;
- Numerous slope stability assessments including highways and active railway embankments and bridges showing signs of failure and provision of remedial design options;
- Design of treatment works for underground mine workings and mine entries.
- Emergency works on housing schemes where remedial underpinning was necessary.
- We have undertaken Regulation 33 Geotechnical Assessments in accordance with the Quarries Regulations in existing quarries or opencast mines.
- Working platform design for mobile plant.
Project Example: Economic Link Road, Cross Hands
Following the completion of investigation and treatment of historical mine working across Phase 2b of the new Economic Link Road in Cross Hands (Llandeilo Road to Norton Road), ESP have been appointed to undertake the next phase of works to determine the nature and extent of underground coal mine workings within the ‘Big’ coal seam.
The initial stages comprise systematic drilling within of proposed road footprint in accordance with a methodology agreed with the Coal Authority. This is to determine the nature, depth and extent of the mine workings and assessment of the potential subsidence risk to the proposed road. This will be followed by ground treatment to stabilise the mine workings and ultimately validation to verify the success of the remedial works.
Project Example: Stability Design of High Rock Slopes, Fyndaff Opencast
ESP previously provided specialist stability design of high rock slopes and geotechnical assistance on this legacy Coal Mining project in South Wales. The Fyndaff opencast mine lies on the northern edge of the South Wales coalfield and exhibits major faulting and folding (as can be seen in the photo inset) within the economic coal seams.
Project Example: Piling Platform Design, Cardiff
ESP were instructed in the design of a piling platform in an area of variable ground conditions, including areas of reportedly organic-rich soils and contamination, which was being remediated. An understanding of the ground conditions beneath the platforms and the consideration of these conditions was crucial in generating the appropriate, bespoke Conceptual Ground Model (CGM) for the project. From this CGM, appropriate design values were determined and the working platform design completed.
A selected list of example projects can be found on our Projects and Technical page.