Blar i NTNU Open på emneord "VDP::Andre geofag: 469"
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Conceptual models for rock burst and energy transformations in strain burst
(Chapter, 2020)The occurrence of a rock burst event depends on two requisites: the secondary stresses after rock excavation must be beyond the rock strength and there are excessive energy releases from the rock mass in addition to the ... -
Cyclic oedometer swelling tests on rocks from North-Central Luzon, Philippines
(Chapter, 2020)Tunnels passing through swelling rocks are subjected to stability problems as moisture changes affect the material properties of the rocks. The drying out process during construction may cause local contraction stresses ... -
Design of unlined pressure tunnels in Norway – limitations of empirical overburden criteria and significance of in-situ rock stress measurements
(Chapter, 2020)A key requirement for unlined pressure tunnels is confinement, i.e. that the minimum principal stress must exceed the internal water pressure. Failure to meet this requirement can cause hydraulic jacking of the rock mass, ... -
Different mechanisms of Arctic first-year sea-ice ridge consolidation observed during the MOSAiC expedition
(Peer reviewed; Journal article, 2023)Sea-ice ridges constitute a large fraction of the ice volume in the Arctic Ocean, yet we know little about the evolution of these ice masses. Here we examine the thermal and morphological evolution of an Arctic first-year ... -
Numerical simulation of pore pressure in rock joints during pressure transient in an unlined hydropower tunnel
(Chapter, 2020)Recent experimental result shows that pressure transients of both short and long time periods; i.e. water hammer and mass oscillation; can travel into the rock mass of an unlined hydropower tunnel through rock joints. It ... -
Performance of a fully grouted GFRP rock bolt under combined pull and shear loading
(Chapter, 2020)Glass Fiber Reinforced Polymer (GFRP) rock bolts is gaining attention, as an alternative to steel bolts, for permanent rock support in civil underground infrastructures like road tunnels. GFRP holds many advantages for ... -
Quantifying false bottoms and under-ice meltwater layers beneath Arctic summer sea ice with fine-scale observations
(Peer reviewed; Journal article, 2022)Kartlegging av ferskvannslag og dannelse av falsk bunnis under sjøisen ved sommarsmelting i sentrale Polhavet Sjøisen i Polhavet er i rask endring. Den er blitt mye tynnere i løpet av de siste tiårene, havet og atmosfæren ... -
Shale Creep as Leakage Healing Mechanism in CO2 Sequestration
(Journal article; Peer reviewed, 2017)Experiments on shale specimens targeted creep deformation in order to investigate whether this mechanism could be relied upon to close fractures and stop leakage near injection wells. Uniaxial compression tests were conducted ... -
Snowmelt contribution to Arctic first-year ice ridge mass balance and rapid consolidation during summer melt
(Peer reviewed; Journal article, 2023)Sea ice ridges are one of the most under-sampled and poorly understood components of the Arctic sea ice system. Yet, ridges play a crucial role in the sea ice mass balance and have been identified as ecological hotspots ... -
Temporal evolution of under-ice meltwater layers and false bottoms and their impact on summer Arctic sea ice mass balance
(Peer reviewed; Journal article, 2023)Nåtidens endringer av havisen i Polhavet medfører ikke bare tynnere is og redusert isutbredelse, men også endringer i utbredelsen av eldre, flerårig is. Gjennom de siste 20 årene har andelen med flerårig havis, havis som ...