###Contact mechanics of geomaterials
Project ID: 2228bd1100 (You will need this ID for your application)
Research Theme: Engineering
UCL Lead department: Civil, Environmental and Geomatic Engineering (CEGE)
Lead Supervisor: Beatrice Baudet
Project Summary:
Geomaterials commonly encountered, such as natural soil grains or rock fill used in dams, have complex shapes and often rough texture. Both will affect their inter-particle contact behaviour and therefore their mechanical response at the engineering scale. Models for granular soil and rock behaviour on the other hand often disregard their particulate behaviour, treating them like continuum materials such as steel, although much research has focused on simulating individual discrete particles but generally represented by spheres with simple expressions of the contact between them. While the most advanced research today aims at developing discrete element soil models using more realistic shapes, thanks to advanced imaging techniques allowing better particle shape description and enhanced computational capacity, the texture scale is usually neglected. This is because of the experimental difficulty of characterising surface roughness and the real contact area between particles, a continuing subject of research for materials scientists because of the experimental complexities. As a result, classic contact models have been modified to include roughness, but they tend to be simplistic and were developed for metals and engineered surfaces and therefore not easily applied to geomaterials. With this project, it is proposed to go beyond those models by investigating the real contact area between particles and the mechanics at the contact, experimentally and numerically. Key collaborations with partners in imaging or physics will allow performing those complex measurements: the contact area and deformation at the contact will be measured by testing two particles in contact while x-ray CT scanning (Grenoble University), surface roughness and contact area will be quantified using interferometry (Imperial College) and micro-fluorescence (Amsterdam University). The information will be used to inform discrete element modelling at UCL. A student with a good BEng/MEng in civil or mechanical engineering will be required to carry out experiments and develop numerical models.