The Ground Investigation of the Year category rewards innovation and excellence in site investigation, surveying and monitoring. The judges were looking for evidence of project delivery; partnering capabilities; relationships with clients, project partners, stakeholders and the community; and delivery of growth.
Arup and Concept Site Investigations – Television Centre, Wood Lane, London
The Television Centre project comprises the phased redevelopment of the existing BBC Television Centre in London into a complex of residential and commercial buildings. Geotechnically, the scheme comprises deepening basements, reuse of existing foundations and retaining walls. The project was delivered within a reasonable timeframe by adopting a proactive and flexible approach in overcoming the logistical and access difficulties. The flexibility of the approach meant critical information to inform design and construction planning for the rest of the project was obtained in a safer and more sustainable way.
Atkins, Horizon Nuclear Power and Structural Soils – Wylfa Newydd detailed onshore ground investigation
The Wylfa Newydd project is being developed by Horizon Nuclear Power. Its objective is to build and operate a new nuclear power station using the Advanced Boiling Water Reactor design developed by Hitachi-GE. Horizon commissioned Structural Soils and Atkins to conduct the site investigation. The key to the project was using experienced and competent personnel at all levels with credible experience and who could deliver the project’s requirements for quality, work planning, scope development and definition, site work, in-situ and laboratory testing and interpretation of geotechnical parameters. By working closely together, Horizon, Structural Soils and Atkins successfully met the project milestones of starting on site in March 2014 and delivering the first interpretative report in December 2014.
Centre for Smart Infrastructure and Construction (CSIC), University of Cambridge – Monitoring of a sprayed concrete tunnel lining using distributed fibre optic strain sensors at Crossrail Liverpool Street Station
The scope of the project was to record the effect of cross-passage excavation on the strain distribution within the sprayed concrete lining (SCL) of a tunnel, in order to enable more efficient SCL design and construction. A distributed fibre optic strain (DFOS) sensing system was embedded within the primary SCL thickening of an enlargement chamber in Crossrail’s Liverpool Street Station concourse tunnel. Using Brillouin Optical Time Domain Reflectometer (BOTDR) technology, distributed strain measurements were taken along the embedded cables before, during and after the excavation of cross-passages on both sides of the tunnel. The empirical data provided by the project is being disseminated to stakeholders and presented in scientific fora and publications.
Offshore Wind Consultants (part of the Aqualis Offshore group) – East Anglia Offshore Wind Farm site investigation
The project consisted of an offshore site investigation to inform the foundation design for what will be the largest offshore wind farm in the world if developed. The investigation comprised 24 composite CPT/sampling boreholes within the windfarm and 112 seabed CPTs distributed between windfarm and export cable route, undertaken by two separate vessels during summer 2014. Offshore Wind Consultants says this site investigation was particularly innovative as it involved pile resistance calculations performed live with purpose written simplified software incorporating the “ICP” approach. The boreholes were continued until the on-vessel calculations showed that piles to the depth investigated were sufficient to withstand anticipated design loads, resulting in appropriate and site specific depths and a significant saving of potential site investigation costs for the client.
Parsons Brinckerhoff – Cinderford northern quarter spine road ground investigation, Forest of Dean
Parsons Brinckerhoff’s original scope of works was to undertake a ground investigation, geotechnical design and detailed design of two junctions at either end of the proposed spine road that forms part of the brownfield redevelopment at Cinderford northern quarter, Forest of Dean. Due to external factors, Parsons Brinckerhoff’s commission was substantially extended by the client, to provide these services for the delivery of the entire 1.4km spine road, inclusive of the junctions. The works were delivered under budget and on time despite a substantial scope change driven by client requirements, and a legacy of low quality or missing historical data to aid the design of the ground investigation.
Soil Engineering Geoservices with the Morgan Sindall, Vinci and Bachy Soletanche joint venture – West Ham ground investigation
The investigation was initiated by the Morgan Sindall, Vinci and Bachy Soletanche joint venture (MVB JV) following an encounter with unforeseen ground conditions during construction of the Thames Water Lee Tunnel within the Chalk at depths in excess of 70mbgl. Soil Engineering Geoservices (SEGL) and MVB JV designed the ground investigation to ensure maximum data could be obtained given the highly variable and mixed nature of the geology anticipated. To drill though the sewer, SEGL and MVB JV designed and manufactured a bespoke collaring system for “clean drilling” which prevented migration of effluent and residue from the sewer either downhole or upwards during the drilling process. Total collaboration and a shared understanding of the criticalness of the works contributed to the successful outcome of this project in terms of safety, value, and programme delivery.
United Utilities – Ground investigation for the reuse of a tunnel drive shaft at Anchorsholme Park, Blackpool
The works at Anchorsholme Park, near Blackpool, form part of United Utilities (UU) Fylde Strategy to address environmental issues driven by the EU Bathing and Shellfish Water Directives to improve water quality. The aim of the project is to provide additional storm water storage to the system to reduce the current level of spills. Phase 1 works required improvement of the hydraulic connection to the Fylde Coast Tunnel (FCT) to achieve a spill frequency position. The FCT represents the “main artery” of the sewer network. The ground investigations were used to determine the viability risk and opportunity to recover and modify a temporary shaft, 12A, to facilitate this connection. It was concluded that the risk associated with works in this shaft were too great and too difficult to manage during construction and did not deliver the required benefits within AMP5.
Volker Stevin, Boskalis Westminster and Atkins joint venture – Crag End landslip, Rothbury, Northumberland
The VolkerStevin, Boskalis Westminster and Atkins joint venture designed a supplementary ground investigation to inform geotechnical interpretation and facilitate the design of slope remedial works. Instrumentation was required to monitor slope movement and to measure the piezometric water levels within the slope and record changes in level with time and in response to climatic conditions and rainfall events. The supplementary ground investigation was carefully planned with water pumps and pipework, a Siltbuster water-treatment unit (chemical flocculation), silt netting and straw bales available to appropriately manage the artesian groundwater to prevent pollution of the SSSI, including the River Coquet. An innovative system was designed for installing instrumentation under artesian groundwater conditions by erecting scaffolding to balance the artesian pressures to stop flow, therefore preventing grout washout.
Waterman – Caithness Moray Shetland HVDC connection and Noss Head HDD landing, Wick, Scotland
In August 2014 Scottish Hydro Electric Transmission (SHE Transmission) committed to an upgrade of part of its Transmission network in the north of Scotland. The central element of this upgrade was an underground and subsea high voltage direct current (HVDC) transmission cable connecting Caithness and Moray. The works involved several new techniques for ground investigation, most notably undertaking a trial horizontal directional drill and using BIM to integrate data from various sources into a 3D ground model which can continue to be developed as the main works progress. As lead consultant for the project, Waterman says the investigation represents a pioneering advance in predicting HDD behaviour by utilising BIM to develop a 3D ground model and HDD profile.