GEOEDUCATION – A Guide to Site Investigations

The nature of the ground upon which a well-designed structure sits is ultimately key to its success.

That’s according to HBPW Geoenvironmental Engineer, Elin Griffiths. “The design of a structure which is economical and safe to construct, with durability and low maintenance costs, depends upon an adequate understanding of the nature of the ground earmarked for the development. This understanding comes from an appreciation of the distribution of the materials in the ground, and their properties and behaviour under various influences and constraints during the construction and lifetime of the structure. An adequate and properly structured site investigation is, therefore, an essential part of any civil engineering or building project.”

She said that inadequate site investigations might be the result of a lack of awareness of those hazards associated with the ground, inadequate focus on finance, insufficient time or a lack of geotechnical expertise.

“The approach adopted for a site investigation, its extent and the techniques used, will all depend upon site-specific circumstances, and the experience and judgement of those involved,” she added. “It is usual for the site investigation to be a phased exercise and the following four phases might run consecutively, or even have long periods between them:-

Phase 1 —Preliminary Risk Assessment/ Desk Study and Reconnaissance Survey

Phase 2 —An intrusive investigation, this may comprise boreholes, trial pits, penetration tests, laboratory tests and geophysical methods with a report which includes the identification of problem areas that require additional investigation and consideration.

Phase 3 —Design of a remediation strategy (if required) or clarification of particular technical requirements to provide adequate information for design and construction.

Phase 4 — Validation and Monitoring of remediation during the construction phase.

“It is essential that the information obtained from each phase is assessed to ensure that the original objectives of the site investigation are satisfied. Changes to the scope of the investigation, or design proposals, might be needed in the light of any unexpected findings. At HBPW we offer a holistic approach to site investigation to ensure that clients get exactly what they need.”

Want to know more? Elin can be at HBPW Geotechnics on 01777 869 896 or via email at e.griffiths@hbpwconsulting.co.uk.