Modelling infrastructure installation
Deformations alter the pore pressures and the strength and stiffness of the soil. Understanding and predicting the installation effects is critical when considering the quality and long-term reliability of infrastructure. New models developed as part of the EU-funded project 'Modelling installation effects in geotechnical engineering' (GEO-INSTALL) will enable engineers and scientists to consider the effects of installation in practical geotechnical problems. Researchers studied installation effects with analyses utilizing finite element and material point methods (MPM). MPM is a new mesh-free particle-based method with some similarities with the finite element method. GEO-INSTALL made major advances in constitutive soil models, considering static, cyclic and dynamic loading, by developing and implementing new user-defined models for clays and sands. Combining these models with MPM, enabled scientists to model issues such as sand liquefaction. The team developed a new finite element technique for modelling periodic ground improvement (installations at regular intervals to improve foundation soil) exploiting so-called a volume averaging technique. The model is currently being validated against field test results. Embedded pile models have been improved and the algorithms are incorporated in PLAXIS finite element software for geotechnical professionals. Most civil engineering applications, such as excavations and construction of foundations for buildings and infrastructure require careful analysis of deformations and stability. The advances made to modelling software, simulating large deformations, will greatly enhance our possibilities to account for installation effects, improving the effectiveness and reliability of geotechnical constructions.
Keywords
Infrastructure, structural elements, installation effects, piles, soil, deformations, constitutive models, finite element method, material point method, volume averaging, PLAXIS