UK soil parameters and EC7 factors
Illustrative Values Only: These parameters are for preliminary assessment and must be verified against site-specific investigation data before use in detailed design.
Made Ground
Heterogeneous fill material, composition varies significantly
Alluvium
River-deposited sediments, typically soft to firm clays and silts with sand/gravel lenses
River Terrace Deposits
Gravel and sand deposits from ancient river systems
Glacial Till (Boulder Clay)
Ice-deposited material, typically stiff to very stiff clay with gravel, cobbles and boulders
London Clay
Stiff to very stiff fissured clay, Eocene age
Lambeth Group
Variable sequence of clays, silts, sands and gravels (formerly Reading/Woolwich Beds)
Thanet Sand
Dense to very dense fine sand, Palaeocene age
Chalk
Soft to hard limestone, Cretaceous age. Properties vary with grade (A-D)
Mercia Mudstone
Weak to moderately strong mudstone, Triassic age
Coal Measures
Interbedded mudstones, siltstones, sandstones and coal seams, Carboniferous age
Sand (Generic)
Generic sand parameters - use site-specific data where available
Gravel (Generic)
Generic gravel parameters - use site-specific data where available
Clay (Generic)
Generic clay parameters - use site-specific data where available
Silt
Fine-grained soil with intermediate properties between sand and clay
Peat
Organic soil with very high compressibility
Select a soil type to view parameters