Geophysical and Utility Surveys
Geophysical surveys provide the opportunities to locate and identify variations in the subsurface through non-invasive methodologies. Identification of natural and man-made features such as cavities, buried obstructions, utilities and other geological variations can help to reduce the risk of unforeseen ground conditions for designers and developers.
RSK offers comprehensive geophysical surveying services for the construction industry. Expert knowledge of a wide range of geophysical techniques including ground-penetrating radar, microgravity, electrical resistivity tomography, electromagnetics, seismic and magnetics allow us to offer bespoke survey solutions for a broad range of applications. Our team of highly experienced and skilled professional geophysicists deliver expert advice, design, execution and reporting services.
Our knowledgeable Geosciences team, and subsidiary Central Alliance, with senior staff chartered through the Geological Society, apply state-of-the-art geophysical instrumentation to the identification of subsurface variations associated with man-made and natural ground conditions. We deliver high-quality surveys, extensive equipment resources and an integrated industrial and academic research portfolio with an excellent safety, health, environment and quality (SHEQ) record, so our clients are assured of receiving a comprehensive, high-quality service that upholds industry-leading standards.
Experience and knowledge
Different sites offer wide-ranging opportunities for applying geophysical investigation techniques. From large-scale geological site characterisation for critical infrastructure projects to identifying the presence of a chimney flue for a redevelopment project, our team of geophysical experts can provide advice on when to safely apply geophysical techniques. Thanks to our team’s extensive experience, we can design surveys appropriate to site conditions and apply innovative techniques to locate subsurface voids, from identifying unrecorded historical mine entries to mapping badger sets. We have the skillset to apply a range of geophysical techniques to detect and map discontinuities in subsurface or structure properties and can apply this to a wide range of projects, from locating large-scale faults to identifying cracks in concrete.
Whether its defining the extents of a buried air-raid shelter or tracing the location of a buried electric cable, our team can expertly map all complexities below the surface in the urban environment. We ensure work is completed safely, deploying appropriate techniques in challenging situations, and provide innovative solutions to our clients’ problems. We maintain close links with UK universities, ensuring we are at the forefront of research and development and applying new ideas and methods to the commercial sector.
Team of experts
Our extensive range of in-house services allows us to apply the most appropriate techniques to best identify a target or to characterise a site. Our geophysical team is aligned closely with our geotechnical and allied technical teams meaning that RSK is able to offer fully integrated multidisciplinary site investigation solutions.
Our clients know that when they trust RSK with their geophysical and utility survey requirements, they will receive a high-quality service tailored to their needs. With a responsive, client-focused approach, we endeavour to provide comprehensive surveys, identifying challenges early and producing solutions curated to the requirements of the site.
Ground penetrating radar
Applications of ground-penetrating radar (GPR) are broad and varied owing to the versatility of use in urban environments. GPR is most commonly used to confirm the position of buried utilities, with specific benefits to locate non-metallic utilities that electromagnetic locators cannot detect.
Seismic techniques, including refraction, reflection and multichannel analysis of surface waves, rely on the propagation of an acoustic signal through the ground to determine variations in the subsurface properties. The techniques can be applied well to rural and greenfield environments, and to redevelopment sites and ground stiffness investigations. Seismic techniques can also be deployed within boreholes.
Injecting an electrical current into the ground and measuring the potential difference between varying sets of electrodes allows an image of the subsurface to be compiled. The technique is best applied in a greenfield setting or areas of soft standing and can be used to assess varying geological conditions, including faults, depth to bedrock, and man-made and natural cavities.
This technique can be used to determine the presence of voided or low-density ground. An expert survey design with high-quality data acquisition and processing allow for features such as historical mine workings, collapse and dissolution features, faults and other man-made subsurface structures to be identified.
Often deployed for quick and economical site reconnaissance surveys, electromagnetic techniques and instrumentation provide versatile survey tools to map variable ground conditions. Uses include locating buried infrastructure and obstructions, and mapping variations in shallow geological conditions and variations and extents of made ground and waste.
Safeground utility clearance
Safeground is RSK’s buried infrastructure detection and mapping service. Providing on-site mark-out surveys ahead of ground-breaking activities, Safeground’s aim is to keep the workforce safe by reducing cable strikes and promoting safe digging practices.
PAS128 Utility Mapping
Utilising GPR technologies, RSK can offer PAS-128-compliant utility surveys, often utilising post-processed GPR to ensure that we can deliver information to the highest standards in the PAS guidelines. Drawings can be issued in 2D or 3D as required.
All of our utility drawings integrate record information with on-site survey data, and we always assign quality levels to detected features. This approach allows end-users a greater understanding of, and confidence in, our final deliverables.
Desk-based utility reports
RSK can obtain statutory service records for a site. Providing a full report to list affected and unaffected providers in the context of a combined report, we are also able to digitise records to provide a combined digital record of the searches. Records are delivered in line with PAS 128 recommendations for Level D searches.