Professor Ashraf Osman's Outputs (9)

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

A simple model for tertiary creep in geomaterials (2019)
Journal Article
Osman, A., Birchall, T., & Rouainia, M. (2020). A simple model for tertiary creep in geomaterials. Geotechnical Research, 70(1), 3-59. https://doi.org/10.1680/jgere.19.00025

This paper presents a constitutive modelling approach to the viscoplastic-damage behaviour of geomaterials. This approach is based on the hyperelasticity framework where the entire constitutive behaviour is derived from only two scalar potentials: a... Read More about A simple model for tertiary creep in geomaterials.

Analysis of a laterally loaded rigid cylinder embedded in an elastoplastic (2019)
Journal Article
Hashem Ali, S., & Osman, A. (2020). Analysis of a laterally loaded rigid cylinder embedded in an elastoplastic. Results in engineering, 5, Article 100062. https://doi.org/10.1016/j.rineng.2019.100062

An analytical approach has been developed to predict the response of a rigid disc embedded in elastoplastic media. The governing differential equations are obtained using the principle of minimizing the potential energy. The displacement components i... Read More about Analysis of a laterally loaded rigid cylinder embedded in an elastoplastic.

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.

Upper bound solutions for the shape factors of smooth rectangular footings on frictional materials (2019)
Journal Article
Osman, A. S. (2019). Upper bound solutions for the shape factors of smooth rectangular footings on frictional materials. Computers and Geotechnics, 115, Article 103177. https://doi.org/10.1016/j.compgeo.2019.103177

Limit analysis of smooth square and rectangular footings is presented in this paper. Three dimensions multi-block collapse mechanism with kinematically admissible velocity field is developed. The rigid blocks in this mechanism are truncated by conica... Read More about Upper bound solutions for the shape factors of smooth rectangular footings on frictional materials.

Analysis of maximum arching conditions in active plane-strain trapdoors in sand (2019)
Journal Article
Osman, A. S., & Jacobsz, S. (2019). Analysis of maximum arching conditions in active plane-strain trapdoors in sand. Computers and Geotechnics, 113, Article 103089. https://doi.org/10.1016/j.compgeo.2019.05.004

The trapdoor problem is a useful model to understand the stress distribution around geo-structures. This paper focuses on evaluating the conditions of maximum arching (minimum loads on trapdoors) developing during the lowering of plane-strain active... Read More about Analysis of maximum arching conditions in active plane-strain trapdoors in sand.

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.

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.