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To verify and find issues on the generalised scaling law for dynamic centrifuge tests, a series of centrifuge model tests are conducted under the scheme of the modelling of models technique. In a series of dynamic tests on a flat, saturated sand layer, four different centrifugal accelerations from 5 g to 70 g are applied to the scaled models for which the prototype is uniquely given. With the scaling law, the prototype is scaled down to 1/100. The models are exposed to sinusoidal input accelerations with 0·65 Hz and amplitudes of 2·1 m/s2 and 3·1 m/s2 in prototype scale. For response during shaking, nearly identical accelerations and excess pore-water pressure build-ups are recorded for all the cases in the prototype scale. Discrepancies are found on surface settlements and duration time for dissipation of excess pore-water pressure. The major cause of the discrepancy may be the small value of the shear modulus induced by the low confining stress in model ground under low centrifugal acceleration.

This paper presents recent innovations implemented in the LaRiMiT (Landslide Risk Mitigation Toolbox) webtool. These include an innovative methodology for utilising experts’ scoring of landslide risk mitigation measures directly within the decision support tool, and updating of the tool’s database over structural measures to include many nature-based solutions (NBS) for mitigating landslide risk. Landslides are a common and treacherous natural hazard, and due to the effect of climate change on the frequency and intensity of extreme weather events, climate-driven landslides are expected to become more frequent. This negative trend is a driving factor for developing decision-support solutions for risk mitigation, and the LaRiMiT toolbox and the expert scoring methodology presented in this article contribute to meeting these needs. Selecting suitable structural measures is complicated due to factors such as site-specific conditions, local knowledge and resources, socio-economic constraints, and environmental considerations. LaRiMiT uses user-input attributes of site-specific slope movements combined with expert scoring of the suitability of various mitigation solutions to identify and select appropriate mitigation measures from an extensive database of structural solutions. While the LaRiMiT database initially included only conventional (grey) solutions relying on traditional methods, it has been recently expanded to include nature-based solutions (NBS), which are sustainable techniques for managing erosion and mitigating shallow landslides using vegetation and the use of natural materials. NBS and conventional solutions can also be combined to provide hybrid solutions. The proposed methodology for implementing expert scoring is dynamic and iterative, consisting of statistical pooling of experts’ scores collected via online surveys, and consolidating these into an expert scoring utility embedded in the LaRiMiT web portal engine. An initial application of this methodology has been tested by surveying a set of landslides experts, mostly in Europe, and applying it to the structural measures database in the LaRiMiT tool. Although the number of experts in this initial application is limited, dynamic updating of the scoring allows the tool to continuously improve as additional experts contribute.

The evolution of cities is directly linked to their subsurface: the local geology and hydrogeology alongside the history of human interventions are the basis for the present structure and organisation of cities and affect the prospects for future developments within and above the ground. The underground serves multiple purposes in cities including; providing stability for buildings, providing drinking water and materials, serving as a heat source or retention basin, and accommodating infrastructure and developments. In the face of growth predictions and climate change, interdependencies between urban planning objectives and the subsurface, such as placing infrastructure underground to release surface congestion, remediation of brownfields for development, or prospecting for geothermal energy, become ever more important. This paper reviews current initiatives in industry, policy and research in the UK, which aim for changes in urban subsurface management and governance. It identifies the multitude of planning topics in which the subsurface implicitly features, many of which are commonly only addressed at project level. It highlights that the wider impact of these interventions on underground space and the development of the city is not considered. Consequently, the value of the subsurface for sustainable and resilient development of cities may not be realised.