Geotechnical Engineering

Excavation sequences and support installation

Anything can be calculated today, the question is, whether the method is appropriate and what features need to be abstracted. Furthermore, a correct and technically profound interpretation of the calculated results is essential for a reliable design of complex underground structures. Based on 50 years of tunnelling and underground infrastructure experience, AMBERG defines the correct analysis method, relevant questions to be asked and integrates the entire process into the overall design process.

The custom – tailored analysis is performed with highest competence and efficiency, and the answers to the questions are prepared in an easy-to-understand, logical way. The special knowledge of AMBERG employees allows the seamless transfer from complex geometries from 3D BIM-Models into the numerical modelling software. This allows detailed and efficient geotechnical analysis and supports the design and goes hand in hand with the BIM Modelling.

Services

Semmering Base Tunnel – numerical model of the shaft head caverns SBT 1.1

Model Building

2D and 3D Modelling of complex underground structures (caverns, underground stations, tunnel intersections, etc.) with AutoCAD and Rhino
Modelling of weakness zones and geological features
Seamless geometry transfer from the 3D-BIM-Model into the meshing module with Griddle (Rhino Plugin from Itasca)
Geometry and mesh Clean-up and De-Featuring of existing 3D-Models
Import of external loads from 3rd party structures (foundations, piles, cables)
Inclusion of support (shotcrete, rock bolts, etc.)
Multi-Stage models and complex excavation sequences
Custom-developed scripts for various detailed tasks are used: excavation sequence automatization, parameter studies, back analysis and results evaluation.

Semmering Base Tunnel – numerical model of the cavern expansion at shaft foot SBT3.1

Discontinuous numerical analysis

Data acquisition via remote sensing equipment (photogrammetry) and reliable and fast determination of all relevant structural information (joint orientation, persistence, spacing et cetera)
Check of potential block failure due to the presence of unfavourably orientated discontinuities
Analysis of cases where the failure mechanism can’t be identified reliably beforehand, and the stress-in duced failure is in direct interaction with the present discontinuities
Transfer of structural data (persistence, orientation, frictional properties) of the discontinuities into the model
Application of advanced modelling techniques (prob abilistic joint networks) based on the remote sensing results
Support design and validation (shotcrete, rock bolts) according to technical standards

Brenner Base Tunnel – numerical model of the emergency station St. Jodok

Continuous numerical analysis

Identification of critical areas and stress concentrations in the rock (e.g., weakness zones, remaining pillars, areas of increased interference)
Determination of all relevant field variables (stress, strain, displacements etc.)
Support design and validation (shotcrete, rock bolts)
Displacements, surface settlements and influences on 3rd party structures (buildings, tunnels, streets, etc.)
Experience with all state-of-the-art constitutive laws (Mohr-Coulomb, Hoek-Brown, Hardening Soil, etc.)
In-house implementation of custom tailored, empirical constitutive laws (brittle failure according to Diederichs and Martin, etc.)
Verification of serviceability
Development of monitoring concepts (comparison of calculation and measurement data), their validation and back analysis

Competence

Extensive expertise
Top experts in Rock Mechanics and numerical modelling
Advanced modelling and simulation tools (ROCSCIENCE, ITASCA, RHINO, Plaxis)
Experience with solving complex non-standard problems
Advanced library of evaluation tools: we don’t deliver colourful, meaningless plots, but palpable and interpretable data

Benefits

Applied know-how customised to your requirements and infrastructure project
Integration of BIM Modelling with geotechnical analysis and support design
Optimisation of complex underground structures
Reduction of construction cost
Determination of specific monitoring concepts

Selected references

Project

Semmering Base Tunnel, Austria

Services

Modelling and numerical investigation of the shaft head caverns in construction lot SBT1.1 and of the cavern expansion at shaft foot in lot 3.1: Design of rock support, verification of serviceability

Client

ÖBB INFRA

Project

Tunnelbana Stockholm, Sweden

Services

Modelling and numerical investigation of the complex underground construction circumstances with implementation of the complex fault zone structure: Design of rock support, sensitivity analysis regarding the fault zone influence, verification of serviceability, development of optimal construction sequence, numerical discontinuity analysis and permanent support validation, compilation of the relevant monitoring variables to be observed.

Client

WSP

Project

Brenner Base Tunnel – Construction lot H51, Austria

Services

Modelling and numerical investigation of the emergency station St. Jodok

Client

BBT SE

Project

Hydropower plant Grimsel 3, Switzerland

Services

Modelling and numerical investigation of powerhouse and transformer caverns.

Client

KWO (Kraftwerke Oberhasli AG)