Optimising Site Investigations using a Risk-Based Approach

Michael P. Crisp

May 20, 2019

It is well accepted that, in civil engineering construction projects, the largest element of financial and technical risk generally lies beneath the ground. Indeed, structural foundation failure, construction over-runs and delays can often be attributed to inadequate and/or inappropriate site investigations.

Unfortunately, geotechnical engineers have, at their disposal, limited guidance when designing the extent and nature of site investigations. Almost exclusively, the scope of geotechnical investigations is not governed by what is needed to characterise appropriately the subsurface conditions but, rather, is driven by budgetary constraints. A pressing need is to arm geotechnical engineers with a series of guidelines that link the scope of a site investigation to ground variability and the probability that the foundation will be under-designed, resulting in some form of failure, or over-designed, resulting in the foundation being larger and more costly than needed. This presentation outlines research currently being undertaken to develop such guidelines, focusing on the design of shallow and deep foundations in variable ground using the probabilistic techniques of random field theory and Monte Carlo simulation.

Resources

SIOPS (site investigation optimisation for piles using statistics) is a versatile command-line tool for optimising geotechnical site investigations, allowing the user to quickly analyse the performance of a wide range of investigations. Download on Github

Relevant papers, related to this presentation, can be found on ResearchGate.