Strategy

Geotechnical engineering based on sound scientific and engineering principles will produce safe, economic, sustainable structures that are fit for purpose. The behaviour of soils is a function of the composition, structure, fabric and properties. The greatest risk is associated with the ground investigation and ground modelling. Ground is spatially and temporally variable making it difficult to form a complete picture of the ground conditions. Ground models including topographical, geomorphological, geological, hydrogeological and geotechnical models based on prior information and results of multi-stage ground investigations are used to manage risk. Design can be based on deterministic analyses assuming the worst case scenario to allow for uncertainty or risk based design which combines the uncertainty and complexity of the ground with the consequence of the failure of the structure. Numerical analyses using complex constitutive models allows the ground response to be explored to optimise the design and understand and reduce risk. The success of this approach is very dependent on the quality of the ground model to understand the ground conditions. This is especially the case with problematic soils. A strategic approach incorporates a multi stage ground investigation, development of appropriate ground models, representative properties based on a probabilistic analyses and use of numerical methods to optimise the design and reduce the risk.