Geotechnical Investigation, Highways
Introduction:
We were instructed to undertake an assessment at three town centre sites in Bromsgrove, Worcestershire, as part of a highways improvement scheme designed by Burroughs and on behalf of Worcestershire County Council. The three sites were located in the heavily trafficked and pedestrianised Bromsgrove town centre, requiring complex planning of both the site investigation procedures and Health and Safety measures for both workers and members of the public. Our factual and interpretive reports were in accordance with HD22-08 (Highways Agency, 2008).
Details:
Our input comprised desk study reviews (preliminary sources study) of the individual sites and geotechnical investigation to obtain the engineering characterisitcs and properties of the shallow soils, along with assessment of potential risks posed by contamination.
The investigations generally comprised hand excavated inspection pits, the measurement of in-situ CBR values (using DCP equipment), and the collection of cores through the existing highway.
The town centre location of the sites posed significant restraints on the geotechnical investigation, including risks from vehicular traffic and a dense network of underground utility services. The proximity of the works to members of the public and related risks required the adoption of extensive health and safety measures. We identified variable ground conditions across the sites including geotechnical risks posed by potentially compressible strata and extensive underground services. Furthermore, the sites were identified as being highly sensitive to pollution, being located on a Principal Aquifer and within an aquifer Source Protection Zone.
Our factual and interpretive reports were in accordance with HD22-08 (Highways Agency, 2008).