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Conference paperVire A, Spinneken J, Piggott MD, et al., 2014,
MODELLING OF WAVES AND WAVE-STRUCTURE INTERACTIONS USING NON-LINEAR NUMERICAL MODELS
, 11th World Congress on Computational Mechanics (WCCM) / 5th European Conference on Computational Mechanics (ECCM) / 6th European Conference on Computational Fluid Dynamics (ECFD), Publisher: INT CENTER NUMERICAL METHODS ENGINEERING, Pages: 2138-2148 -
Journal articleForzoni A, Storms JEA, Whittaker AC, et al., 2014,
Delayed delivery from the sediment factory: modeling the impact of catchment response time to tectonics on sediment flux and fluvio-deltaic stratigraphy
, Earth Surface Processes and Landforms, Vol: in press -
Conference paperXutong L, Bell RE, Wrona T, et al., 2014,
Drilling a virtual core in the Gulf of Corinth
, MAGELLAN Plus/NERC UKIODP Workshop -
Book chapterVire A, Jiang J, Piggott MD, et al., 2014,
Towards the Numerical Modelling of Floating Offshore Renewables
, Fluid-Structure-Sound Interactions and Control, Editors: Zhou, Yang, Huang, Hodges, Publisher: Springer Berlin Heidelberg, Pages: 413-417, ISBN: 978-3-642-40370-5 -
Conference paperZdravkovic L, Potts DM, Tsiampousi A, 2014,
Obtaining factors of safety from a finite element analysis of unsaturated soils
, 6th International Conference on Unsaturated Soils (UNSAT), Publisher: CRC PRESS-TAYLOR & FRANCIS GROUP, Pages: 553-559 -
Conference paperMeasham PG, Taborda DMG, Zdravković L, et al., 2014,
Numerical simulation of a deep excavation in London Clay
, Delft, 8th European Conference on Numerical Methods in Geotechnical Engineering, NUMGE 2014, Publisher: Taylor and Francis - Balkema, Pages: 771-776The requirement for accurate modelling of the small-strain stiffness behaviour of soils in numerical analysis has been driven by the need to establish serviceability limit states for geotechnical structures. A common approach when tackling this problem is to employ a non-linear elastic constitutive model coupled with an appropriate failure criterion. The latter establishes the shear strength of the material and allows the evaluation of plastic deformations at large strains, while the former typically reproduces the effect of stress and strain levels on the shear and bulk stiffness of the soil. This paper evaluates distinct strategies for reproducing the stiffness of a material within the context of a new small-strain stiffness model. After introducing the constitutive model and describing its key features, a procedure to determine its parameters is proposed and demonstrated for London Clay. Subsequently, the relative impact of the different methods of interpreting the effect of changes in strain path direction on the stiffness of the material is investigated by performing finite element analyses of a deep excavation in London Clay. © 2014 Taylor & Francis Group, London.
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Conference paperHughes T, Taborda DMG, Zdravkovíc L, et al., 2014,
Predicting the settlement of footings on sand using a bounding surface plasticity model
, Delft, 8th European Conference on Numerical Methods in Geotechnical Engineering, NUMGE 2014, Publisher: Taylor and Francis - Balkema, Pages: 675-680Despite having been the subject of extensive research, the prediction of load-settlement response of footings on sand deposits currently yields relatively poor and unreliable results. This paper aims at providing insight into this problem by examining the ability of a bounding surface plasticity model to predict the response of four distinct footings on Perth sand, which were tested as part of an international prediction event. Given the complexity of the chosen constitutive model and the relatively limited ground information available, emphasis is placed on the calibration procedure. In particular, the contributions of specific components of the constitutive model, such as the ability to simulate stiffness degradation at small deformation levels and the adopted formulation for the plastic hardening modulus, are investigated in a parametric study. Axisymmetric finite element analyses demonstrate that the response of the footings measured in the field is adequately simulated using the selected constitutive model. © 2014 Taylor & Francis Group.
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Conference paperTsiampousi A, Vitsios I, Zdravkovic L, et al., 2014,
Effect of previous stress history and vegetation on the coefficient of earth pressure at-rest, K<sub>0</sub>, in London clay
, 8th European Conference on Numerical Methods in Geotechnical Engineering (NUMGE), Publisher: CRC PRESS-TAYLOR & FRANCIS GROUP, Pages: 209-214- Author Web Link
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- Citations: 1
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Journal articleNeal WD, Appleby-Thomas GJ, Collins GS, 2014,
Meso-scopic deformation in brittle granular materials
, 18TH APS-SCCM AND 24TH AIRAPT, PTS 1-19, Vol: 500, ISSN: 1742-6588- Author Web Link
- Open Access Link
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- Citations: 7
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Journal articleBell RE, Jackson CA-L, Whipp PS, et al., 2014,
Strain migration during multiphase extension: observations from the northern North Sea. In press
, Tectonics -
Journal articleJackson CA-L, Rodriguez CR, Rotevatn A, et al., 2014,
Geological and geophysical expression of a primary salt weld; an example from the Santos Basin, Brazil. In press
, Interpretation -
Conference paperBell RE, Duffy O, Jackson CA-L, et al., 2014,
Long term (> 250 Ma) and long length-scale (>300 km) strain migration along a rift border fault
, Geometry and Growth of Normal Faults -
Conference paperBell RE, Jackson CA-L, 2014,
Are current models for normal fault array evoltion applicable to natural rifts?
, Geometry and Growth of Normal Faults -
Journal articleKamal RH, Coop MR, Jardine RJ, et al., 2014,
The post-yield behaviour of four Eocene-to-Jurassic UK stiff clays
, GEOTECHNIQUE, Vol: 64, Pages: 620-634, ISSN: 0016-8505- Author Web Link
- Open Access Link
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- Citations: 31
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Book chapterMannie AS, Holgate NE, Jackson CAL, 2013,
Get outside
, 52 Things You Should Know About Geology, Publisher: Agile Geoscience, Pages: 30-31, ISBN: 0987959425 -
Journal articleMcPhillips D, Bierman PR, Crocker T, et al., 2013,
Landscape response to Pleistocene-Holocene precipitation change in the Western Cordillera, Peru: 10Be concentrations in modern sediments and terrace fills
, Journal of Geophysical Research: Earth Surface, Vol: 118, Pages: 2488-2499, ISSN: 2169-9011The landscape response to climate change is frequently investigated with models because natural experiments on geologic timescales are rare. In Quebrada Veladera, in the western Andes Mountains, the formation of alluvial terraces during periods of high precipitation presents opportunities for such an experiment. We compare drainage-average erosion rates during Pleistocene terrace deposition with Holocene rates, using cosmogenic 10Be samples for seven pairs of quartz sand taken from the trunk and tributaries of Quebrada Veladera and adjacent terraces. Each pair consists of sediment collected from the modern channel and excavated from an adjacent fill terrace. The terrace fill was deposited at ~16 ka and preserved an isotopic record of paleoerosion rates in the Late Pleistocene. Modern sands yield 10Be concentrations between 1.68 × 105 and 2.28 × 105 atoms/g, corresponding to Holocene erosion rates between 43 ± 3 and 58 ± 4 mm/kyr. The 10Be concentrations in terrace sands range from 9.46 × 104 to 3.73 × 105 atoms/g, corresponding to paleoerosion rates from 27 ± 2 to 103 ± 8 mm/kyr. Smaller, upstream tributaries show a substantial decline in erosion rate following the transition from a wet to dry climate, but larger drainage areas show no change. We interpret this trend to indicate that the wetter climate drove landscape dissection, which ceased with the return to dry conditions. As channel heads propagated upslope, erosion accelerated in low-order drainages before higher-order ones. This contrast disappeared when the drainage network ceased to expand; at that point, erosion rates became spatially uniform, consistent with the uniformity of modern hillslope gradients. Key Points Landscape response to climate change evaluated with 10Be erosion rates Wetter climate associated with rapid erosion in smaller, upstream drainages Drier, Holocene climate associated with spatially uniform erosion rates ©2013. American Geop
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Journal articleCiesla FJ, Davison TM, Collins GS, et al., 2013,
Thermal consequences of impacts in the early Solar System.
, Meteoritics and Planetary Science, Vol: 48, Pages: 2559-2567, ISSN: 1086-9379 -
Journal articlePutnam AE, Schaefer JM, Denton GH, et al., 2013,
Warming and glacier recession in the Rakaia valley, Southern Alps of New Zealand, during Heinrich Stadial 1
, Earth and Planetary Science Letters, Vol: 382, Pages: 98-110, ISSN: 0012-821XThe termination of the last ice age featured a major reconfiguration of Earth's climate and cryosphere, yet the underlying causes of these massive changes continue to be debated. Documenting the spatial and temporal variations of atmospheric temperature during deglaciation can help discriminate among potential drivers. Here, we present a 10Be surface-exposure chronology and glaciological reconstruction of ice recession following the Last Glacial Maximum (LGM) in the Rakaia valley, Southern Alps of New Zealand. Innermost LGM moraines at Big Ben have an age of 17,840 ± 240 yrs, whereas ice-marginal moraines or ice-molded bedrock surfaces at distances up-valley from Big Ben of 12.5 km (Lake Coleridge), ~25 km (Castle Hill), ~28 km (Double Hill), ~43 km (Prospect Hill), and ~58 km (Reischek knob) have ages of 17,020 ± 70 yrs, 17,100 ± 110 yrs, 16,960 ± 370 yrs, 16,250 ± 340 yrs, and 15,660 ± 160 yrs, respectively. These results indicate extensive recession of the Rakaia glacier, which we attribute primarily to the effects of climatic warming. In conjunction with geomorphological maps and a glaciological reconstruction for the Rakaia valley, we use our chronology to infer timing and magnitude of past atmospheric temperature changes. Compared to an overall temperature rise of ~4.65°C between the end of the LGM and the start of the Holocene, the glacier recession between ~17,840 and ~15,660 yrs ago is attributable to a net temperature increase of ~4.0°C (from -6.25 to -2.25°C), accounting for ~86% of the overall warming. Approximately 3.75°C (~70%) of the warming occurred between ~17,840 and ~16,250 yrs ago, with a further 0.75°C (~16%) increase between ~16,250 and ~15,660 yrs ago. A sustained southward shift of the Subtropical Front (STF) south of Australia between ~17,800 and ~16,000 yrs ago coincides with the warming over the Rakaia valley, and suggests a close link between Southern Ocean frontal boundary pos
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Book chapterHolgate NE, Mannie AS, Jackson CAL, 2013,
As easy as 1D, 2D, 3D
, 52 Things You Should Know About Geology, Editors: Hall, Publisher: Agile Geoscience, Pages: 18-19, ISBN: 0987959425 -
Journal articleJackson CAL, Lewis MM, 2013,
Physiography of the North Permian Basin margin: new insights from 3D seismic reflection data
, Journal of the Geological Society, Vol: 170, Pages: 857-8603D seismic reflection data from the Egersund Basin, offshore Norway image geomorphic features that record mid-Permian, footwall degradation of basin-bounding fault systems. This ancient landscape was subsequently flooded during the pan-European, Late Permian transgression of the North Permian Salt Basin, and was fossilised beneath Zechstein Supergroup evaporites. We provide the first conclusive evidence for pre-Zechstein normal faulting in the Egersund Basin, indicating that extensional strain was shared between Permian and Late Jurassic-to-Early Cretaceous rift events.
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