This award celebrates a scheme with a ground engineering contract value of less than £1M that stands out in terms of its credentials in innovation, quality, sustainability, health and safety and value engineering. Entrants had to explain and provide evidence to demonstrate what exceptional measures were taken to result in the project being delivered above the expected standard. A key element in deciding the winner will be the contribution of the entrant to the overall delivery of a project.
keller hi res
Aarsleff Ground Engineering
Birmingham Resilience Scheme
birmingham resilience scheme
The £300M scheme is one Severn Trent Water’s biggest infrastructure projects and will develop an alternative water supply for Birmingham. A pumping station will pump water along a new 25km pipeline through 1m diameter pipes to treatment works.
Aarsleff installed a bespoke temporary sheet piled cofferdam to facilitate the new pumping station and allowed a dry working area for partner J Murphy to construct the secant piling to the intake structure. Sheet piles were then removed and the entire structure submerged.
Mayfair retrofit basement
mayfair retro fit
A remodelling and refurbishment of seven-storey mid-terrace included the construction of a new single storey basement with swimming pool and hydraulic lift. The sensitive adjoining listed buildings and significant surcharge loading proved challenging for both the temporary and permanent works design.
Internal load bearing walls supported on temporary piles were installed and which doubled up as permanent supports once the basement was complete. The basement retaining structure was formed using contiguous bored pile walls with subsequent hybrid reinforced concrete liner wall.
Aecom, Story and Network Rail
Storm Desmond caused the re-activation of a historic 500,000t landslide on the Settle to Carlisle railway, triggering significant movement of the up line, cess support structure and railway embankment. It was to become one of the largest landslide repair challenges ever tackled in the UK rail industry.
Using a risk-informed and reliability-based design approach, the remedial work involved constructing a piled concrete slab, supported by two rows of contiguous tubular steel piles, with an upstand retaining wall providing support to the track.
Cambrian Rock Cutting Campaign
cambrian rock cutting campaign 2
The Network Rail project addresses issues with rock and soil cutting assets in North Wales where the condition of the rock faces present a significant safety and performance risk to the operational railway. Six sites are being targeted by the campaign and will receive de-vegetation, de-scaling, topographical surveys, ground investigation, asset proofing and stabilisation.
To date approximately 13,000m² of rock slopes have been treated and over 600 rock bolts installed to secure the faces.
B4058 Horsley Hill Slip
b4058 horsley hill slip
When the southbound carriageway on the B4058 in Gloucestershire collapsed at the end of 2013, GI showed the 12m failed zone had been constructed on a wedge of made ground, while the northbound carriageway was constructed on Birdlip Limestone Formation and Bridport Sand Formation. In addition, the footway had dropped by 1m over a 30m length.
The remedial design involved 94 precast “L” sections installed 2m below the carriageway level and anchored into the underlying rock bed.
A90 sheet pile retaining wall
a90 sheet pile retaining wall
For part of the Aberdeen Western Peripheral Route, a temporary works design for a replacement bridge carrying the A90 trunk road over the B979 was undertaken.
An anchored sheet pile retention structure allowed the existing bridge to be cut longitudinally, demolished sequentially and rebuilt in two halves. The retaining wall provided support to the bridge approach embankments, firstly retaining the northbound carriageway, then waling beams and anchors were switched to the opposite side to provide retention to the southbound lanes as the build was completed.
Soil Engineering Geoservices
Shieldhall Tunnel, Titwood Road grouting
Scottish Water’s Shieldhall Tunnel is the biggest upgrade of the authority’s waste water network. Soil Engineering Geoservices was appointed to carry out remediation works to consolidate abandoned mine workings within four different coal seams and an old pit shaft, before tunnel construction began.
A total of 2162t of grout was injected into 381 infill treatment holes, 379 perimeter treatment holes and 22 test holes sunk along the route. In addition, 633t of grout was injected into 32 mine shaft treatment holes to consolidate the pit shaft.
United Utilities and Mott Macdonald Bentley
Upper Chelburn Reservoir
This 200-year-old impounding reservoir near Rochdale was identified to have several potential failures, including suffusion, internal erosion and lack of spillway capacity.
With no original construction records, limited post construction data, and the mixed quality historical borehole sampling returning low quality data, it was decided to use digital technologies to create an interactive 3D model and remove the need for further GI. This enabled targeting of grouting works and pile lengths, the determination of the spillway foundations, effects of landslips and uplift pressures to be managed within the final design.
WSP and Kier Highways
A66 Bassenthwaite Lake Slip
a66 bassenthwaite lake slip
The stabilisation of a 120m length of slope on the A66, towards the northern end of Bassenthwaite Lake in Cumbria was needed after cracks and monitoring confirmed that there was a potential risk of failure of the slope.
Ground investigation, geophysics, remote groundwater monitoring and inclinometers were used to develop the ground model. The solution called for the installation of 1600 self-drilling soil nails on the extremely steep slope and allowed for site adjustments, resulting in shorter nails being used.