A5019501349- Soil and Unsaturated Flow
- Landslides and related hazards
- Geotechnical Engineering and Soil Mechanics
- Geothermal Energy Systems and Applications
- Rock Mechanics and Modeling
- CO2 Sequestration and Geologic Interactions
- Grouting, Rheology, and Soil Mechanics
- Hydraulic Fracturing and Reservoir Analysis
- Climate change and permafrost
- Drilling and Well Engineering
- Groundwater flow and contamination studies
- Geotechnical Engineering and Soil Stabilization
- Geotechnical Engineering and Analysis
- Geotechnical and Geomechanical Engineering
- Dam Engineering and Safety
- Geotechnical Engineering and Underground Structures
- Microbial Applications in Construction Materials
- Integrated Energy Systems Optimization
- Landfill Environmental Impact Studies
- Solar Energy Systems and Technologies
- Tree Root and Stability Studies
- Hydrocarbon exploration and reservoir analysis
- Seismic Imaging and Inversion Techniques
- Concrete and Cement Materials Research
- Spacecraft and Cryogenic Technologies
École Polytechnique Fédérale de Lausanne
2016-2025
ETH Zurich
2019
Virginia Tech
2017
Johnson Foundation
2017
King Abdulaziz University
2013-2016
Georgia Institute of Technology
2013-2014
University of California, Davis
2013-2014
Duke University
2006-2013
University of Vermont
2011
Université Libre de Bruxelles
2011
Consideration of soil as a living ecosystem offers the potential for innovative and sustainable solutions to geotechnical problems. This is new paradigm many in engineering. Realising this requires multidisciplinary approach that embraces biology geochemistry develop techniques beneficial ground modification. paper assesses progress, opportunities, challenges emerging field. Biomediated geochemical processes, which consist reaction regulated by subsurface microbiology, currently being...
The geothermal use of concrete geostructures (piles, walls and slabs) is an environmentally friendly way cooling heating buildings. With such structures, it possible to transfer energy from the ground fluid-filled pipes cast in then building environments. To improve knowledge field behaviour a pile subjected thermo-mechanical loads studied situ. aim study increased on due thermal effects. maximum increment applied order 21°C mechanical load reached 1300 kN. Coupled multi-physical finite...
Abstract The paper presents the results of an experimental study thermal effects on mechanical behaviour a saturated clay. was performed CM clay (Kaolin) using temperature‐controlled triaxial apparatus. Applied temperatures were between 22 and 90°C. A comprehensive program carried out, including: (i) shear tests at ambient high for different initial overconsolidation ratios; (ii) consolidation temperatures; (iii) drained heating ratios. obtained provide observations concerning wide scope...
Abstract The effective stress principle, conventionally applied in saturated soils, is reviewed for constitutive modelling purposes. assumptions the applicability of Terzaghi's single are recalled and its advantages inventoried. possible frameworks applicable to unsaturated soil reassessed a comparative manner, specifically Bishop's stress, independent variables approach generalized framework. latter considerations lead definition unified context, suitable soils under different saturation...
This paper presents the results of a comprehensive experimental study desiccation fine-grained soils. Air drying initially saturated soil slabs in controlled conditions is investigated by performing three kinds tests: free tests, constrained tests (prevented shrinkage), and crack pattern tests. Strains, suction, water content, geometry are investigated. Results reveal that unconstrained exhibits two stages: domain with large, mostly irrecoverable deformations degree saturation close to 100%,...
Energy piles are an effective and economic means of using geothermal energy resources for heating cooling buildings, contributing to legislative requirements renewable in new construction. While such have been used around 25 years with no apparent detrimental effect, there is limited understanding their thermo-mechanical behaviour. This paper synthesises the results from three published field studies illustrates some engineering behaviour during cooling. Simplified load transfer mechanisms a...
There is currently a lack of established calculation methods for the geotechnical design heat exchanger piles, although technology experiencing fast expansion. Instead quantifying effects temperature changes on static behavior common practice to apply large overall security factor. This done be side safety with respect thermal effects. The few existing in situ experiments show that applying load induces significant change stress-strain state pile. paper presents numerical analysis method...
Behaviour of the pile–soil interface is important to correctly predict response floating piles in terms displacement and lateral friction. Regarding energy piles, which couple structural roles deep foundations with principle shallow geothermal energy, interfaces influenced by seasonal daily cyclic thermal variations. Accordingly, goal this paper experimentally investigate at different temperatures. This experimental campaign aims analyse (i) mobilization shear strength soil–pile that induced...
The behaviour of a pile subjected to thermo-mechanical loads was studied in situ with the aim quantifying thermal influence on bearing capacity heat exchanger piles. To accomplish this, situated building under construction equipped pipe system inject into it using special pump. Load cells, deformation gauges, and thermometers were installed evaluate during seven tests coupled loads. temperature variations applied order 15°C mechanical load reached 1300 kN. results permitted quantification...
Abstract The complete determination of soil water retention curves requires the sample volume to be measured in order calculate its void ratio and degree saturation. During drying pressure plate apparatus, cracks often appear altering deformation evaporation patterns. Consequently, this causes a significant scatter measurement when using displacement method. This paper proposes simple method avoid cracking, by limiting friction adhesion boundary effects, allow for unrestrained shrinkage...
MX-80 bentonite used in engineered barrier systems would be subjected to wetting and drying cycles. To assess the response of material under such circumstances, a comprehensive experimental characterisation water retention behaviour compacted granular was performed this study. A new methodology is proposed investigate constant volume condition for specimens prepared at different dry densities. The hydraulic paths, including cyclic variations content. As result, an irreversible modification...
A full-scale experimental site with four energy test piles was built on the campus of Swiss Federal Institute Technology in Lausanne, Switzerland. This used to investigate interaction effects within a group piles. First, ground constraints were evaluated by testing without any structure top. Next, each pile individually tested once overlying built, which provided information structural and allowed quantification pile–structure–pile interactions. Finally, simultaneously heated quantify...
The operation of energy piles in summer can expel excess heat the buildings into ground by use a pump. Despite having been implemented for decades, design still relies heavily on empiricism, as there is limited understanding about heating effects pile capacity. A series centrifuge model tests aluminum medium dense saturated sand reported this study to investigate settlement patterns well capacities single piles. In total, four in-flight load under three different temperatures, namely 22, 37,...
The behaviour of conventional pile groups (e.g. closely spaced) that are subjected to mechanical loads has been shown be different from the single isolated piles. so-called ‘group effects’ responsible for this and must considered an optimal design foundations. In recent years, energy piles have potential work as both structural supports geothermal heat exchangers, thus thermal loads. An increasing amount research investigated previously unexplored impact on thermo-mechanical However, no...
We introduce the application of microbial-induced calcite precipitation via ureolytic soil bacterium Sporosarcina Pasteurii in freeze-dried form, as a means enhancing overall MICP efficiency and reproducibility for geotechnical engineering applications. show that execution urea hydrolysis CaCO3 persist "cell-free" mechanism upon complete breakdown rehydrated cell clusters. Further, strength stiffness parameters bio-cemented sands are determined. Medium-grained sand yields compressive...
Summary This paper presents a dynamic fully coupled formulation for saturated and unsaturated soils that undergo large deformations based on material point method. Governing equations are applied to porous while considering it as continuum in which the pores of solid skeleton filled with water air. The accuracy developed method is tested available experimental numerical results. has been investigate failure post‐failure behaviour rapid landslides slopes subjected rainfall infiltration using...
The paper presents an experimental and modelling approach for the soil-water retention behaviour of two deformable soils. objective is to investigate physical mechanisms that govern properties propose a constitutive framework curve accounting initial state compaction deformability A granular soil clayey were subjected drying over wide range suctions so residual saturation could be attained. Different densities tested each material. curves (SWRCs) obtained are synthesized compared in terms...
Summary Energy geostructures are rapidly gaining acceptance around the world; they represent a renewable and clean source of energy that can be used for heating cooling buildings de‐icing infrastructures. This technology couples structural role with supply, using principle shallow geothermal energy. The exploitation represents an additional thermal loading, seasonally cyclic, which is imposed on soil structure itself. Because primary piles stability superstructure, this aspect needs to...