Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Modern Geotechnical Codes of Practice and New Design Challenges Using Numerical Methods for Supported Excavations
Eurocode 7 (EC7), which is the geotechnical engineering design standard in Europe, introduces the concept of partial safety factors and distinguishes between Serviceability Limit State (SLS) and Ultimate Limit State (ULS). While EC7 allows the use of Finite Element Methods (FEM) for ULS, there is limited guidance in a number of issues. The thesis focuses on a number of constitutive models of increasing complexity and both the characteristic and design values of the model parameters are derived for the London Clay and a soft Marine clay. The challenges associated with factoring the undrained shear strength when using total and effective stress parameters are discussed. The use of FEM for ULS design of supported excavations, is highlighted using simple excavation examples and two deep excavation case histories; the Moorgate Crossrail Station and the Exhibition Road Building of the Victoria & Albert Museum. The different factoring combinations and strategies, required by EC7, are compared in terms of the calculated design internal structural forces, illustrating that the use of more advanced models can have significant advantages. Moreover, comparisons are made between the design prop loads calculated from the FEM and a number of empirical methods. The HYD limit state, as described in EC7, relates to the upward flow of water through the soil towards a free surface. The HYD verification, using FEM, can be performed with two approaches; the soil block approach by calculating the equilibrium of a rectangular soil block and the integration point approach by checking that the equilibrium is satisfied at each integration point. Thorough comparisons between the two approaches using benchmark geometries illustrate the benefits of using more advanced approaches for such stability verifications.
Modern Geotechnical Codes of Practice and New Design Challenges Using Numerical Methods for Supported Excavations
Eurocode 7 (EC7), which is the geotechnical engineering design standard in Europe, introduces the concept of partial safety factors and distinguishes between Serviceability Limit State (SLS) and Ultimate Limit State (ULS). While EC7 allows the use of Finite Element Methods (FEM) for ULS, there is limited guidance in a number of issues. The thesis focuses on a number of constitutive models of increasing complexity and both the characteristic and design values of the model parameters are derived for the London Clay and a soft Marine clay. The challenges associated with factoring the undrained shear strength when using total and effective stress parameters are discussed. The use of FEM for ULS design of supported excavations, is highlighted using simple excavation examples and two deep excavation case histories; the Moorgate Crossrail Station and the Exhibition Road Building of the Victoria & Albert Museum. The different factoring combinations and strategies, required by EC7, are compared in terms of the calculated design internal structural forces, illustrating that the use of more advanced models can have significant advantages. Moreover, comparisons are made between the design prop loads calculated from the FEM and a number of empirical methods. The HYD limit state, as described in EC7, relates to the upward flow of water through the soil towards a free surface. The HYD verification, using FEM, can be performed with two approaches; the soil block approach by calculating the equilibrium of a rectangular soil block and the integration point approach by checking that the equilibrium is satisfied at each integration point. Thorough comparisons between the two approaches using benchmark geometries illustrate the benefits of using more advanced approaches for such stability verifications.
Modern Geotechnical Codes of Practice and New Design Challenges Using Numerical Methods for Supported Excavations
Katsigiannis, Georgios (Autor:in)
28.11.2017
Doctoral thesis, UCL (University College London).
Hochschulschrift
Elektronische Ressource
Englisch
DDC:
621
Robust geotechnical design of braced excavations in clays
| Online Contents | 2014
Robust geotechnical design of braced excavations in clays
| British Library Online Contents | 2014
Practical Robust Geotechnical Design of Supported Excavations—A Case History of Excavation in Taiwan
| British Library Conference Proceedings | 2017