Ground Engineering
From the investigation plan to the foundation recommendation: we investigate the ground, derive characteristic soil parameters and carry out the verifications that the structural engineer and the permitting authority need – as a geotechnical report (ground investigation report) for residential and industrial buildings, energy supply, transport and utility projects.
Send a project enquiryor call: +49 157 88 330112
Investigation and report
The geotechnical report is the outcome of every project. How much investigation it needs is decided beforehand – from the available data, the geotechnical category and the structure.
Optimising the investigation
We set the number, location and depth of the exploratory points so that the results are reliable without paying for unnecessary metres of drilling. The basis is an evaluation of geological maps, borehole archives and terrain models before the first probe goes in.
DIN 4020 · DIN EN 1997-2 · Geotechnical category GC 1–3Cone penetration tests, boreholes, window sampling
We plan the field programme, tender it, supervise the fieldwork and check borehole logs and laboratory results for plausibility. Fieldwork by established partner companies; evaluation and responsibility in our office.
DIN EN ISO 22475-1 · DIN EN ISO 22476-1/-2 · DIN EN ISO 14688-1/-2 · DIN 18196Interpretation of cone penetration tests
Cone resistance, sleeve friction and pore water pressure are normalised, classified and divided into layers using the soil behaviour type index; from these, relative density, oedometer modulus and undrained shear strength are estimated for each layer using empirical correlations and checked against boreholes and laboratory values.
Robertson (1990 / 2009 / 2016) · DIN EN 1997-2 · DIN EN ISO 22476-1Geotechnical report
Ground model, characteristic values, design groundwater level, foundation recommendation, homogeneous zones for the tender, notes on excavated soil, dewatering and risks – in a form that the structural engineer, specialist designers and the authority can use directly.
DIN 4020 · DIN EN 1997-1 · VOB/C DIN 18300Foundations and verifications
The ground model is turned into numbers: bearing pressure and bearing resistance, settlement, stability. Where empirical values are not enough, we carry out numerical analyses.
Geotechnical verifications to Eurocode 7
Bearing failure, sliding, overturning, uplift and hydraulic heave at the ultimate limit state, deformations at the serviceability limit state – with the partial factors to DIN 1054 for the relevant design situation.
DIN EN 1997-1 with NA · DIN 1054Settlement analysis and settlement simulation
Settlements and differential settlements for pad, strip and raft foundations, where required as two- or three-dimensional numerical analysis – for example next to existing buildings or in highly variable ground.
DIN 4019 · Finite element analysisPile design and deep foundations
Pile resistance from shaft resistance and base resistance, pile lengths, group effect and recommendation of the pile system – derived from cone penetration tests and laboratory parameters.
DIN EN 1997-1 · EA-PfähleExcavations and groundwater
Where the excavation base lies below the groundwater table, dewatering determines costs and the duration of the permitting process. That is why we plan excavation and dewatering together.
Excavation design, excavation support and anchors
Earth pressure assumptions, design of sheet pile, soldier pile (Berlin-type) or bored pile walls, strutting and tie-back anchoring, verification of the excavation base against hydraulic heave.
DIN 4124 · EAB · DIN EN 1997-1Dewatering concept and permit application
Design of the groundwater lowering with pumping rate, well layout and radius of influence, prediction of the cones of depression and of settlements in the surrounding area – including the documents for the water-law permit.
§§ 8, 9 WHG · Landeswassergesetz · VOB/C DIN 18305 · Pumping test DVGW W 111Verification of safety against uplift
Safety against uplift of basements, watertight tanks and basins for the design groundwater level, with a recommendation on ballasting, anchoring or watertight concrete construction.
DIN EN 1997-1 · DIN 18533 · WU-RichtlinieInfiltration design
Coefficients of permeability from field and laboratory tests, design of swales, infiltration trenches and soakaways, assessment of the depth to groundwater and coordination with the local water authority.
DWA-A 138-1 · DIN 18130-1 · DIN EN ISO 22282Energy and infrastructure structures
Special structures come with their own verifications – and their own clients, who need different information from a structural engineer for buildings.
Wind turbine foundations
Shallow or deep foundations for wind turbines: bearing pressure and base gapping, bearing failure, settlement and tilt, dynamic and static rotational stiffness, modulus of subgrade reaction – matched against the requirements of the turbine manufacturer and the type certification.
DIBt guideline for wind turbines · Check against the type certificationHDD crossings, microtunnelling and inverted siphons
Longitudinal section with ground model along the drill path, homogeneous zones for the tender, assessment of depth of cover, annular pressure and blow-out risk, information for the drilling contractor, launch and reception pits.
VOB/C DIN 18324 · DIN 18319 · DIN EN 1997-2 · DWA-A 125Road and railway construction and mast foundations
Bearing capacity of formation and subgrade, frost resistance, investigation along routes with chainage, foundations for overhead line towers and for structures in the railway area.
ZTV E-StB · Ril 836 · DIN EN 1997-1Crossing sheet: longitudinal section with ground model
SHEET 3 · HDD CROSSING UNDER A LAKE · EXTRACTDrill path, minimum depth of cover, entry and exit angles and the sequence of strata from the exploratory points on both shores on a single sheet – this gives the drilling contractor the information needed for drill head, drilling fluid and reaming. The sheet also shows what is still missing: the shore exploratory points end above the drill path, and the ground below is marked as not investigated.
Request a geotechnical report
Send us the location and the task – we will propose the scope of investigation and the procedure.
Send a project enquiryGoerzallee 299 · 14167 Berlin
+49 157 88 330112
info@geostudys.com