Customer:Horncastle Group
Value: £1,710,000
VHE were appointed to undertake earthworks on a site adjacent to the former runway of BAE Systems in Brough, Humberside.
Following a competitive tender VHE were appointed to undertake the earthworks for a proposed housing development. The works are the first phase of a multi-phase extension to the Brough development masterplan.
A total of over 234,000 cubic meters of earthworks was undertaken, including topsoil excavation; the creation of a surface water storage lagoon with bunds and planted wetland areas including the daylighting of a sewer with outfall and headwalls.
As soils were variable, materials were managed on site throughout the project based on geotechnical properties and their suitability for engineering this included site won clays, sands and gravels from the storage lagoon excavations, reduced level dig in future phase areas and importation using tipper wagons from an off-site source.
Much of the earthworks was undertaken during periods of heavy rainfall, resulting in the material from source being well above the optimum moisture content limits of the initial classification tests undertaken by a UKAS accredited laboratory. Moisture modification was considered and samples were taken to VHE headquarters where bench trials were undertaken in our laboratories of differing additives to bring materials within acceptable limits for compaction to achieve 95% of MDD as required within the specification.
Throughout the project the earthworks required geotechnical validation through a grid of plate testing, CBR, Dynamic cone penetration and mexicone testing on each layer of placement together with sand replacement testing and nuclear density testing for compaction compliance.
VHE provided a mini mobile laboratory to monitor stabilisation performance to control the percentage of additive. Moisture content results pre and post modification were able to be provided to the site team daily.
Constant close volumetric calculations were required by our surveyors and engineers to ensure a balancing of materials on site between processed site soils, reworked post surcharge volumes, stockpiling and recovery of natural materials from the borrowpits and off site imports.
Due to the location of surrounding residential areas, main line railway and River Humber works required careful management of water during heavy rain and environmental monitoring.