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Professor Ashraf Osman's Outputs (27)

Weather Impact on DER Long-term Performance: A Formal Verification Approach (2025)
Presentation / Conference Contribution
Santana, M. A., Stefanakos, I., Fang, X., Garg, A., Sun, H., & Osman, A. (2024, November). Weather Impact on DER Long-term Performance: A Formal Verification Approach. Presented at 2024 IEEE PES Innovative Smart Grid Technologies - Asia (ISGT Asia), Bangalore, India

Distributed energy resources (DERs), such as solar photovoltaic (PV) panels, are essential to modern energy systems, providing resilience and producing clean, local energy. However, their long-term performance is vulnerable to environmental factors,... Read More about Weather Impact on DER Long-term Performance: A Formal Verification Approach.

Estimate end bearing resistance of a circular foundation using small strain and large deformation finite element modelling (2024)
Presentation / Conference Contribution
Zhou, S., Zhang, W., & Osman, A. (2024, April). Estimate end bearing resistance of a circular foundation using small strain and large deformation finite element modelling. Presented at 2024 UK Association for Computational Mechanics Conference, Durham, UK

Accurately predicting the end bearing resistance of the foundation is important for its design and application. This research compares the results of a circular foundation end bearing resistance in uniform clay from small strain finite-element (SSFE)... Read More about Estimate end bearing resistance of a circular foundation using small strain and large deformation finite element modelling.

An Apparatus to Monitor Suction Evolution and Water Migration within a Soil Mass for Climate-Adaptive Infrastructure (2023)
Presentation / Conference Contribution
Rana, A., Kumar Sharma, A., Kumar, A., Azizi, A., Muguda, S., Osman, A., & Toll, D. G. (2023, July). An Apparatus to Monitor Suction Evolution and Water Migration within a Soil Mass for Climate-Adaptive Infrastructure. Presented at Geo-Risk 2023, Arlington, Virginia

The present study investigates the potential utility of a capillary barrier system that limits water infiltration into the underlying soil. This was achieved by developing a cylindrical apparatus capable of monitoring matric suction and water content... Read More about An Apparatus to Monitor Suction Evolution and Water Migration within a Soil Mass for Climate-Adaptive Infrastructure.

Rainfall induced deformation on unsaturated collapsible soils (2021)
Presentation / Conference Contribution
Moghaddasi, H., Osman, A., Toll, D., & Khalili, N. (2022, December). Rainfall induced deformation on unsaturated collapsible soils. Presented at Proceedings of the 4th International Conference on Transportation Geotechnics, Chicago, Illinois, on 23-26 May 2021

The stability of transportation infrastructure can be affected by seasonal rainfall infiltrated adjacent excavations and natural slopes. The paper investigates the rainfall-induced deformation of an anchored excavation constructed in unsaturated soil... Read More about Rainfall induced deformation on unsaturated collapsible soils.

Water retention and characteristic curves representing tropical clay soils from Africa (2020)
Presentation / Conference Contribution
Alhaj, K., Biscontin, G., Elshafie, M., & Osman, A. (2020, December). Water retention and characteristic curves representing tropical clay soils from Africa. Presented at 4th European Conference on Unsaturated Soils (E-UNSAT 2020), ONLINE CONFERENCE

Soil water retention curves (SWRCs) form an essential component of frameworks coupling the hydromechanical behaviour of unsaturated soils. The curves describe how suction changes with variables such as degree of saturation, void ratio and volumetric/... Read More about Water retention and characteristic curves representing tropical clay soils from Africa.

Soil water retention curves representing tropical clay soils from Africa (2019)
Presentation / Conference Contribution
Alhaj, K., Biscontin, G., Elshafie, M., & Osman, A. (2019, December). Soil water retention curves representing tropical clay soils from Africa. Presented at 17th African Regional Conference on Soil Mechanics and Geotechnical Engineering, Cape Town, South Africa

Centrifuge modelling of pile pull-out tests in expansive soil (2019)
Presentation / Conference Contribution
Smit, G., Jacobsz, S., Gaspar, T., & Osman, A. (2019, December). Centrifuge modelling of pile pull-out tests in expansive soil. Presented at Proceedings of the 17th European Conference on Soil Mechanics and Geotechnical Engineering ECSMGE, Reykjavik, Iceland

Designing foundations of wind turbines in expansive soils present a challenge. Piled foundations are often used to mitigate some of the problems associated with construction on expansive soils. Swelling clays frequently occur in an unsaturated state... Read More about Centrifuge modelling of pile pull-out tests in expansive soil.

Preparations for field testing for the performance validation of piled wind turbine foundations in expansive clays (2019)
Presentation / Conference Contribution
da Silva, T., Haigh, S., Elshafie, M., Jacobsz, S., Day, P., & Osman, A. (2019, December). Preparations for field testing for the performance validation of piled wind turbine foundations in expansive clays. Presented at Proceedings of the 17th African Regional Conference on Soil Mechanics and Geotechnical Engineering., Cape Town, South Africa

Field-testing of piles in an expansive clay is required for the validation of the design criteria for wind turbine foundations in such soil profiles. The test programme includes lateral load tests to investigate the horizontal stiffness of the soil a... Read More about Preparations for field testing for the performance validation of piled wind turbine foundations in expansive clays.

Numerical analysis of cavity propagation in deep trapdoor experiments (2019)
Presentation / Conference Contribution
Osman, A., Jacobsz, S., & Purchase, C. (2019, December). Numerical analysis of cavity propagation in deep trapdoor experiments. Presented at Proceedings of the 17th European Conference on Soil Mechanics and Geotechnical Engineering ECSMGE, Reykjavik, Iceland

Large areas of the economically important Gauteng Province of South Africa are underlain by extensively weathered dolomite bedrock in which sinkholes are a common occurrence. Deep trapdoor experi-ments were conducted in the geotechnical centrifuge to... Read More about Numerical analysis of cavity propagation in deep trapdoor experiments.

An expansive clay for centrifuge modelling (2019)
Presentation / Conference Contribution
Gaspar, T., Jacobsz, S., Smit, G., & Osman, A. (2019, December). An expansive clay for centrifuge modelling. Presented at Proceedings of the 17th European Conference on Soil Mechanics and Geotechnical Engineering ECSMGE, Reykjavik, Iceland

This paper explores the development of an expansive soil which can be repeatedly reproduced for use in centrifuge models to investigate soil-structure interaction problems involving expansive soils. The study considered two materials, namely a sand-b... Read More about An expansive clay for centrifuge modelling.

An overview of research activities and achievement in Geotechnics from the Scottish Universities Geotechnics Network (SUGN) (2015)
Presentation / Conference Contribution
Leung, A., Anastasopoulos, I., Augarde, C., Barreto, D., Brennan, A., Brown, M., Connolly, D., Coombs, W., Davies, T., Gao, Z., Ivanovic, A., Kenny, M., Knappett, J., Lombardi, D., McDougall, J., Medero, G., Muir Wood, D., El Mountassir, G., Osman, A., Pytharouli, S., …Zielinski, M. (2015, September). An overview of research activities and achievement in Geotechnics from the Scottish Universities Geotechnics Network (SUGN). Presented at 16th European Conference on Soil Mechanics and Geotechnical Engineering, Edinburgh, UK

ABSTRACT: Design of geotechnical systems is often challenging as it requires the understanding of complex soil behaviour and its influence on field-scale performance of geo-structures. To advance the scientific knowledge and the technological develop... Read More about An overview of research activities and achievement in Geotechnics from the Scottish Universities Geotechnics Network (SUGN).

Data Acquisition Software for Controlling Serial Ports with Cloud Data Storage (2014)
Presentation / Conference Contribution
Asquith, J., & Toll, D. (2014, July). Data Acquisition Software for Controlling Serial Ports with Cloud Data Storage. Presented at 2nd International Conference on Information Technology in Geo-Engineering, Durham, UK

A common requirement of laboratory and field data collection is for automated data logging software to control instrumentation and report on the results. Large projects may require a range of different instrumentation each with its own preferred meth... Read More about Data Acquisition Software for Controlling Serial Ports with Cloud Data Storage.

Data Acquisition and Control Software for Automated Resistivity Measurements (2014)
Presentation / Conference Contribution
Toll, D., & Hassan, A. (2014, July). Data Acquisition and Control Software for Automated Resistivity Measurements. Presented at 2nd International Conference on Information Technology in Geo-Engineering, Durham, UK

Automated multi-electrode resistivity systems now allow rapid and efficient data acquisition of electrical resistivity measurements to address a wide range of hydrogeological, geotechnical and environmental problems. In this work, a flexible data acq... Read More about Data Acquisition and Control Software for Automated Resistivity Measurements.

Modelling tertiary creep in geomaterials using a continuum damage mechanics approach (2014)
Presentation / Conference Contribution
Osman, A., & Birchall, T. (2014, August). Modelling tertiary creep in geomaterials using a continuum damage mechanics approach. Presented at International Symposium on Geomechanics from Micro and Macro, Cambridge, UK

Tertiary creep is often observed in soft rocks and it represents a problem in a mining environment. Tertiary creep behaviour appears due to progressive micro cracking of the material and would result in a loss of strength and stiffness, which may eve... Read More about Modelling tertiary creep in geomaterials using a continuum damage mechanics approach.

On the formulation of thermodynamically-consistent viscoplastic-damage constitutive models (2013)
Presentation / Conference Contribution
Birchall, T., & Osman, A. (2013, March). On the formulation of thermodynamically-consistent viscoplastic-damage constitutive models. Presented at CM13: International Conference on Computational Mechanics., Durham, UK

This paper illustrates the formulation of viscoplastic-damage constitutive models using the framework of hyperplasticity. The entire constitutive behaviour is derived from only two scalar potentials; a free energy potential and a dissipation potentia... Read More about On the formulation of thermodynamically-consistent viscoplastic-damage constitutive models.

Modelling creep in rocks using hyper-plasticity approach (2012)
Presentation / Conference Contribution
Birchall, T., & Osman, A. (2012, December). Modelling creep in rocks using hyper-plasticity approach. Presented at Annual conference of the Association for Computational Mechanics in Engineering, Manchester, England

Dynamic response of a laterally-loaded infinite rigid cylinder embedded in a saturated poroelastic medium (2010)
Presentation / Conference Contribution
Osman, A., & Hussein, M. (2010, December). Dynamic response of a laterally-loaded infinite rigid cylinder embedded in a saturated poroelastic medium. Presented at The International Society for Computing in Civil and Building Engineering (ISCCBE), Nottingham, England

In this paper, an analytical solution for the response of a rigid cylinder embedded in a full-space poroelastic medium subjected to a dynamic lateral load is derived. The problem is idealised as a two-dimensional problem. The solution is obtained usi... Read More about Dynamic response of a laterally-loaded infinite rigid cylinder embedded in a saturated poroelastic medium.

Numerical investigation of the behaviour of suction caissons in structured clays (2010)
Presentation / Conference Contribution
Panayides, S., Rouainia, M., & Osman, A. (2010, December). Numerical investigation of the behaviour of suction caissons in structured clays. Presented at Second International Symposium on Frontiers in Offshore Geotechnics (ISFOG II), University of Western Australia (UWA), Perth

This paper investigates the ultimate capacity of suction anchor foundations, using an advanced constitutive model. The paper explores the effect of changing the aspect ratio of the caisson on the undrained load-carrying capacity of the bucket foundat... Read More about Numerical investigation of the behaviour of suction caissons in structured clays.