
Geoenvironmental Consultants Ltd

Geotechnical Engineering Services & In Situ Testing
Measurement of factors such as groundwater levels, pore water pressures, slope movement and settlement, especially over an extended period, can be vital in assessing long-term risks during ground investigations and determining the best remedial strategy. Implementing cost-effective solutions in geotechnical engineering projects is crucial as it not only ensures safety and sustainability but also leads to significant cost savings for clients. In-situ testing during ground investigations and earthworks is carried out to better characterise the ground conditions and ensure that specifications are being complied with.



Introduction to Geotechnical Engineering
Geotechnical engineering is a crucial aspect of construction and development projects, playing a vital role in ensuring the stability and safety of structures. Geotechnical engineers specialise in the analysis of soil, rock, and groundwater to provide buildable solutions that meet planning requirements. Their expertise is essential in managing geotechnical risks and providing sustainable solutions for clients.
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The field of geotechnical engineering involves the design and construction of permanent geotechnical structures, such as foundations, tunnels, and retaining walls. The primary goal is to ensure the safety and stability of these structures while minimising costs and environmental impact. Geotechnical engineers work closely with other professionals, including civil engineers, architects, and geologists, to provide comprehensive solutions for clients.​
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The importance of geotechnical engineering cannot be overstated, as it has a significant impact on the success of construction and development projects. By providing expert geotechnical services, geotechnical engineers help clients achieve their goals and ensure the long-term sustainability of their projects. Their work is fundamental to the safety and stability of structures, making geotechnical engineering an indispensable part of the construction industry.
Ground engineering principles are fundamental to the practice of geotechnical engineering, providing a framework for understanding the behaviour of soil and rock. Geotechnical engineers apply these principles to design and construct foundations, tunnels, and other underground structures. The principles of ground engineering take into account the properties of soil and rock, including their strength, stiffness, and permeability.
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Geotechnical engineers use ground engineering principles to analyse the stability of slopes and the behaviour of groundwater. This analysis is critical in ensuring the safety and stability of structures, particularly in areas prone to landslides or earthquakes. A thorough understanding of ground engineering principles allows geotechnical engineers to provide effective solutions for clients, addressing potential risks and ensuring the success of construction projects.
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The principles of ground engineering are constantly evolving, with new technologies and techniques being developed to improve the design and construction of geotechnical structures. By staying up-to-date with the latest developments in ground engineering, geotechnical engineers can provide innovative solutions that meet the needs of clients. This continuous advancement in ground engineering principles ensures that geotechnical engineers can address the challenges of modern construction and development projects effectively.
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Geotechnical consultants play a vital role in the development of construction and infrastructure projects, providing expert advice on geotechnical matters. Their primary responsibility is to identify and manage geotechnical risks, ensuring that projects are completed safely and efficiently. Geotechnical consultants work closely with clients to understand their needs and provide tailored solutions that meet their requirements.
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The expertise of geotechnical consultants is essential in ensuring that projects are compliant with relevant regulations and standards. They provide a range of services, including ground investigations, geotechnical design, and construction monitoring. The role of geotechnical consultants is critical in ensuring the success of high-speed projects, such as rail and highway developments.
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By providing expert geotechnical support, consultants can help clients avoid costly delays and ensure that projects are completed on time and within budget. The importance of geotechnical consultants cannot be overstated, as they provide a critical link between the design and construction phases of projects. Their expertise and support are indispensable in achieving the successful execution of construction and infrastructure projects.
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G&J offers a range of geotechnical monitoring and in-situ testing either through our in-house capability or in collaboration with our approved specialist contractors.
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G&J’s in-house capabilities include the following areas:
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Periodic or continuous groundwater level and porewater pressure monitoring, including the use of simple standpipe observation wells, to downloadable ‘divers’, to vibrating wire piezometers;
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Down-borehole inclinometer monitoring to measure ground movement for slope stability assessments;
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Down-borehole extensometer monitoring to measure ground movement for settlement assessments;
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Hand-shear vane testing of cohesive soils, to assess their undrained shear strength;
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TRL Dynamic Cone Penetrometer (DCP) testing to assess the in-situ strength or CBR of shallow soils, and variations within them;
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Soakaway testing to BRE Digest 365 in trial pits or falling head tests in boreholes, to indicate a soil’s permeability.
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G&J can also specify, arrange and supervise:
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Earthworks compliance testing (including core cutter and/or sand replacement tests, plate load tests, CBR testing, Nuclear Density Meter (NDM) testing, and longer-term zone/dummy foundation testing);
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Penetration testing, such as heavy dynamic probing and standard penetration tests (SPT);
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Non-intrusive geophysical surveys such as ground penetrating radar, ground conductivity mapping or resistivity profiles, to help identify variations in the ground, such as changes in geology or the presence of man-made hazards such as old sub-structures or mine shafts;
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Cone Penetration Testing (CPT) to provide almost continuous data on properties such as soil strength and porewater pressure variation with depth;
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Ground settlement monitoring, often performed as part of an earthworks project or when investigating ground subsidence.
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Ground vibration monitoring, typically used to assess the likely effects of site activities such as piling or heavy plant movements on neighbouring properties or structures.
Additionally, G&J provides temporary works design as part of our comprehensive geotechnical services.
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A desk study is an essential component of the geotechnical design process, providing a preliminary assessment of the site conditions. This involves a review of existing data and literature, including geological maps, soil surveys, and environmental reports. The desk study helps geotechnical engineers develop an initial understanding of the site, which is crucial for planning further investigations.
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A site investigation is a more detailed assessment of the site conditions, involving the collection of soil and rock samples and the conduct of in-situ tests. This investigation provides critical data for the geotechnical design, including information on the soil and rock properties. Geotechnical engineers use the data from the desk study and site investigation to develop a comprehensive understanding of the site conditions.
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The desk study and site investigation are critical components of the geotechnical design process, providing a foundation for the development of buildable solutions. By undertaking a thorough desk study and site investigation, geotechnical engineers can identify potential geotechnical risks and develop strategies to mitigate them. The importance of these preliminary assessments cannot be overstated, as they provide a critical foundation for the success of construction and development projects.