The British Geological Survey (BGS) has launched a new range of engineering geology maps which aim to assist in the preparation of tenders, the planning of groundworks and the compilation of ground investigation desk studies.
The maps developed under the BGS Civils brand provide information on the engineering properties of the ground to a depth of 2m.
The BGS Civils suite includes eight national maps at 1:50000 scale, each addressing a key issue faced when planning ground engineering projects.
The strength map indicates the engineering strength of rocks and fine soils, and densities of coarse soils in accordance with BS5930:2015. The discontinuities map, describes features (bedding, layers, foliation) in the rock that could lead to a reduction in strength and provides information about how the ground may break up, for example, whether it is fractured, bedded or massive.
The excavatability map indicates suitable zones for excavation and indicates the type of tool (hand, ripping or blasting tools) needed to dig to 2m depth. The bulking map describes the likely range of increase in volume of the material following excavation from its in situ location. The use as engineering fill map indicates whether excavated material is suitable to be re-used as engineered fill.
The corrosivity and sulfate-sulfide maps provide information about the potential aggressive ground soil conditions, while the resistivity map indicates the electrical earthing properties of the ground.
BGS Civils is a series of digital GIS datasets based on the digital geological map of Great Britain, DiGMapGB-50, which contains descriptive information about the lithological type and variability of each geological unit. This information, coupled with geotechnical data (BGS National Geotechnical Database), information from the literature and expert knowledge, was used to re-attribute DiGMapGB-50 with descriptions relating to the above themes.
BGS Civils is currently supplied by the British Geological Survey as GIS shapefiles and, on request, through a secure web viewer.
The BGS hopes that the data will also be used by developers and entrepreneurs to develop new apps and software to deliver the data to users.