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.
LKAB’s Kiirunavaara Mine is a large, underground, sub-level caving mine that has been seismically active since approximately 2008. With this seismic activity comes associated vibrations. These vibrations can be felt on surface in the town of Kiruna, which is currently located close to the mine on the hangingwall side. The mine is undergoing a national permitting process concerning a desired increased production rate. An important question for this process is: will the increased production rate result in changes to vibrations in the town due to seismicity?
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.
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.
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.
The development of a subsea tidal turbine requires specific research work concerning the design of the foundation in contact with the seabed. This design stage can be simplified by the use of numerical modelling and more particularly by using discrete modelling. HydroQuest asked Cathie Associates to check their previous calculations regarding the behavior of a single steel foundation pin in a granitic rock mass by using Itasca’s discrete numerical approach and follow the forces applied to the pin as well as the state of the damaged zone around the tip during penetration.
As part of phase four in the extension of the ANDRA Meuse/Haute-Marne Underground Research Laboratory, a safety niche (called GT1) will be over-bored into a larger section, then extended. The tunnel axis is 16 m from an auxiliary shaft (named PX). Two perpendicular drifts, called GLN and GLE, connect these 2 excavations.
Junction Dam (2018)
Built between 1959 and 1961, Junction Dam is a double-curvature concrete arch dam located on Silver Creek in El Dorado County, California, just downstream from where Little Silver Creek and South Fork Silver Creek merge. The dam is in a relatively narrow canyon with steep sides and retains the Junction Reservoir.
Boliden Tara Mines is Europe’s largest zinc mine, with an annual production of 2.6 million tones of ore, and has been in operation since 1977. This project was part of the required planning application to the authorities regarding crown pillar extraction in the norther portion of Boliden Tara Mines. It was conducted in two phases – first a continuum model was analyzed in FLAC3D, which was then followed by a discontinuum modelling in 3DEC with included faults.
A baked anode is a complex material, that results from the mixing and baking of different petrol coke grains, with different size distributions, with a pitch. A preliminary study (ICSAS16-CST-MFG-35143-01) developed a PFC2D model accounting for the microstructure of a baked anode, using the Bonded Particle Model (BPM).
Open pit mining often result in high rock slopes, sometimes combined with difficult rock conditions. This is further augmented by large blasting rounds resulting in high vibrations. Reinforcement of pit slope walls is also difficult and many times associated with high costs and loss of production. Bench slope stability is vital for a safe working place for all personnel in the mine as well as for avoiding production loss. Itasca Consultants AB is providing technical, on-site rock mechanics expertise to several open pit mines in northern Sweden.
The Kevitsa open pit mine has been in operation since 2012 and was acquired by Boliden in 2016. A new strategic plan is currently being developed to investigate an increase in production. In conjunction with this, the geotechnical slope design parameters for the final pit depth, including a possibly deeper pit, need to be analyzed.
In the framework of the development of a subsea tidal turbine, the design of the foundations has to be optimal. Cathie Associates, on behalf of HydroQuest, wanted us to investigate the penetration of a single steel foundation pin in a granitic rock mass by using a discrete numerical approach and follow the state of the damaged zone around the tip during penetration.
The city of Kiruna is partly located on the hanging wall side of the LKAB Kiirunavaara Mine. In the long-term perspective, it is not possible to have any residential buildings or infrastructure within the fracture zone and cave zone resulting from mining. An urban transformation process for the Kiruna city center is thus currently underway. The current prognosis is empirical based on observations since the early 1960s until today.
In the context of a wine cellar extension project, a 20cm thick concrete slab is to be constructed on a soil reinforced by rigid inclusions. Itasca France has been called by the design office to verify the mechanical resistance of the concrete slab and assess its settlement under a uniform load.