The Swedish Nuclear Fuel and Waste Management Company (SKB) is planning to extend the short-lived radioactive waste repository with five 275 meters long and one 240 meter long vault. Since the extension could lead to damage on the existing facility, Itasca designed a temporary support system to prevent loose rock.
Wind farm construction requires large cranes to lift massive wind turbine structures over 300 feet tall and exceeding 160 tons. Installing these structures requires many crane “walks”, moving the heavy cranes around 50 miles along soil surfaces of varying strengths. Moving the cranes quickly is critical to installation economics, but this must be done safely by ensuring soil strength stability to avoid sinking or toppling the crane. Conventional best practices require cone penetrometer tests (CPTs) and performing numerical modeling to establish a safe path for moving the cranes requires on the order of four to six weeks. Itasca developed a rapid bearing capacity prediction tool using Python scripts, FLAC3D, and machine learning to provide near real-time feedback on the soil bearing capacity at a location, allowing enhanced crane walk planning.
The objective of the project is to predict the scaling evolution of rock mass effective elastic properties for conditions relevant to the POSE (Posiva’s Olkiluoto Spalling Experiment) niche surroundings at ONKALO, the Finnish site for underground storage of nuclear waste.
In this project, the effects of deformation and rotation with regards to the pile length were observed. Specifically, four piles of a pile bridge were driven through an intermediate sandy layer and may have encountered a local anomaly (Figure 1). A safe assumption was to consider the anomaly to be clay. Additionally, the benefit of any additional helping elements to balance the stiffness distribution of the pile under the pile cap was evaluated.
In general, analysis performed on wind turbine foundations focus on the effects of the foundation’s rotational stiffness and deformation for a range of overturning moments. This project stage focused on the performance of the foundation and, given the local soil condition, its bearing capacity. To evaluate the behavior of the soil-structure interaction, a detailed numerical model of the concrete foundation and its steel reinforcement (i.e., rebar) was built and analyzed in FLAC3D.
SKB is interested in developing a 3D discrete model to predict spalling on the excavation boundaries of underground repositories for the long-term storage of spent nuclear fuel. This project provided a quantitative assessment of modeling spalling using PFC3D to study both lab- and tunnel-scale behavior.
The open pit mine is part of a Greenfield exploration project. Itasca Consultants GmbH in corporation with Itasca Chile were contracted to develop a stability design of the pit. The analysis has been performed using Itasca’s three-dimensional distinct element code, 3DEC (Itasca, 2016).
The road construction department of district Steinfurt, a district in the north of the coal mining area in the Ruhr region, is planning the construction of the new road K 24n. The road axis runs through an area partly affected by old mining operations. These mining operations took place between 1880 and 1921.
Long-term storage of spent fuel is critical to the nuclear energy industry. The Swedish Nuclear Fuel and Waste Management Company (SKB) is developing an approach for the storage of spent nuclear fuel in an underground repository in competent crystalline rock. In order to better understand the spalling damage process, an in-situ test involving the drilling of two boreholes was performed in Äspö diorite at SKB’s underground hard rock laboratory in Äspö. Tests and monitoring were performed on the pillar that separated the boreholes. In order to further investigate the damage process, Itasca performed numerical modeling using PFC3D and FLAC3D.
As part of the EU Horizon 2020 ENIGMA ITN project, ICSAS, the CNRS, and SKB proposed a PhD project entitled “Flow and transport in fracture networks: reducing uncertainty of DFN models by conditioning to geology and geophysical data”, to develop and test a methodology for rock characterization that would help in the decision-making process for an adequate location of the nuclear waste canister burying.
Itasca conducted a seismic performance evaluation of the trestle‐wharf section of the OPC Puerto Cortes Container Terminal, located in Honduras. A FLAC3D analysis of the soil is performed, including the piles and deck of the terminal. This is a fullycoupled, dynamic, soil‐structure, time‐history analysis that quantifies the performance and potential risks for the structure and slope. The Finn model – Byrne formulation was utilized using data from investigation boreholes.
For the construction of the diaphragm‐walls of a cut & cover tunnel in sand‐fill, Itasca Consultores S.L. has been analyzing the stability of the slurry walls of an excavation panel
The development and mining of a deeper seam in a coal mine, located in southern Siberia is planned. ITASCA was tasked with assessing the minimum support pressure and maximum unsupported distance between shield and coal face required to ensure stability of the roof. Also the stress state, displacement field and excavation damaged zone in the roof of the seam were analyzed.
For over five years, Itasca Chile SpA (Itasca) has developed and continuously updated, the 3D numerical groundwater flow model for this open pit mine in Chile. The model is primarily used to estimate pore pressure distributions for past, present, and predictive stages of the pit excavation. These are subsequently used for 3D slope stability analysis. With the new and updated model, new predictions for future stages were made, and new mining and drainage plans were evaluated from a hydrogeological point of view.
In the context of the Greater Paris works, the VINCI-SPIE group builds a future metro station underneath the CNIT centre in Paris, for the westward extension of RER E (EOLE). The West Pre-Station is particularly complex due to its excavation phasing and the presence of many surrounding structures, including among others the T2 tramway line and several foundations.