Imperial College London

PROFESSOR LIDIJA ZDRAVKOVIC

Faculty of EngineeringDepartment of Civil and Environmental Engineering

Professor of Computational Geomechanics
 
 
 
//

Contact

 

+44 (0)20 7594 6076l.zdravkovic

 
 
//

Location

 

530Skempton BuildingSouth Kensington Campus

//

Summary

 

Publications

Publication Type
Year
to

249 results found

Zdravkovic L, Coop MR, 2024, Editorial, Geotechnique, Vol: 74, ISSN: 0016-8505

Journal article

Cui W, Jing H, Potts DM, Dong L, Pedone G, Zdravkovic L, Yao Yet al., 2024, Time-step constraints in coupled hydro-mechanical finite element analysis of unsaturated soils, Computers and Geotechnics, Vol: 165, ISSN: 0266-352X

In the finite element (FE) modelling of transient coupled problems for soils, the associated equations need to be integrated numerically over a time interval during the solution process. A minimum time-step size has been observed to exist, below which spatial oscillations in the obtained solutions can occur. These oscillations might lead to an accumulation of the resultant errors, eventually leading to invalid final predictions. This paper presents an analytical approach for deriving the time-step constraints for FE modelling of the transient behaviour of unsaturated soils with a fully coupled hydro-mechanical (HM) formulation. The effects of both element type and nonlinear soil properties are accounted for in the derivation. The proposed time-step constraints were subsequently verified through a series of coupled HM FE analyses of unsaturated soils, showing an excellent agreement. The present work shows that, when dealing with unsaturated soils, the minimum time-step size depends on the suction range investigated. This dependency derives from the nonlinear variation of water content and permeability with suction, as demonstrated through a set of comparative studies with three different types of unsaturated clays.

Journal article

Solans D, Kontoe S, Zdravković L, 2023, Comparison of a tailings material and a natural sand in seismic site response analyses, Soil Dynamics and Earthquake Engineering, Vol: 175, ISSN: 0267-7261

This article investigates the seismic response of a tailings sand material in the context of site response analysis. The computed response is contrasted with that obtained for an equivalent deposit consisting of a well-characterised natural sand. Initially, the fundamental properties of both materials are used to interpret and compare their behaviour in the framework of Critical State Soil Mechanics (CSSM). Subsequently, both materials' monotonic and cyclic responses are calibrated for an advanced bounding surface plasticity model. Finally, the impact of different calibration approaches is examined through site response analyses under a strong motion. This process identifies fundamental differences between the two geo-materials, impacting the single elements simulations, especially the accuracy of undrained cyclic triaxial tests. The site response analyses examined herein show the impact of the calibrations adopted for both materials in terms of acceleration response spectra, displacements, and excess of pore water pressures (PWP). Although a relatively deep phreatic surface is adopted, the cyclic resistance and permeability of both materials plays a dominant role in the site response characteristics, controlling the excess PWP generation and hence the non-linear behaviour in the soil deposit. Finally, parametric studies are also conducted to explore the impact of permeability of the sands in the site response.

Journal article

Koronides M, Kontoe S, Zdravkovic L, Vratsikidis A, Pitilakis Det al., 2023, Numerical simulation of SSI free and forced vibration experiments on real scale structures of different stiffness, Soil Dynamics and Earthquake Engineering, Vol: 175, Pages: 1-21, ISSN: 0267-7261

Time domain finite element (FE) analysis is a powerful tool for the study of Soil-Structure-Interaction (SSI) phenomena, but it requires a rigorous calibration of all aspects of the numerical model. This study presents three-dimensional (3D) FE analyses that are calibrated and validated against real scale free and forced vibration experiments on the prototype structure of EUROPROTEAS which is founded on soft alluvial sediments. The proposed calibration procedure exploits data recorded during experiments on structures with different structural stiffness, that mobilised SSI effects at different intensities. Particular focus is placed on the modelling of the soil-foundation interface, where zero thickness elastoplastic interface elements are used to allow foundation separation from the soil. A novel approach to simulate contact imperfections (gaps) between the foundation and the adjacent soil is proposed. The results demonstrate the significant impact of the interface gaps and soil nonlinearity on the response of the examined SSI systems, highlighting the importance of a rigorous model calibration.

Journal article

Potts D, Zdravkovic L, 2023, Computer analysis principles in geotechnical engineering, ICE Manual of Geotechnical Engineering: Second Edition, Pages: 37-59, ISBN: 9780727766816

This chapter categorises various forms of computational analysis in geotechnical engineering and explains both positive and negative aspects of their performance. The conventional methods of analysis are considered first, followed by some of the main aspects of advanced numerical analysis.

Book chapter

Dominguez-Quintans C, Harb Carraro JA, Zdravkovic L, 2023, A critical assessment of the effect of initial fabric on key small-strain design parameters of slurry-deposited silts and sands, Journal of Geotechnical and Geoenvironmental Engineering, Vol: 149, Pages: 1-16, ISSN: 1090-0241

Whereas moist-tamped specimens of silts and sands are most used in engineering practice to characterize tailings, offshore sediments, and fluvial/alluvial deposits, design parameters derived from moist-tamping data sets can be significantly different from those obtained from slurry or underwater deposition. This study shows that moist-tamped silty and sandy specimens may exhibit phase transformation at stress ratios that are 25% to 50% lower than those observed for slurry-deposited specimens. Conversely, the small-strain stiffness of the moist-tamped specimens tested can be 50% higher than those from slurry deposition. With tailings dams’ performance receiving increased worldwide attention due to recent dam failures in several parts of the world, this study provides new, specific, and concerning insights about the crucial impact that the selection of moist tamping can have on design parameters. More realistic and rigorous laboratory testing procedures involving tailings remain a key requirement for engineering assessments of tailings behavior. A novel slurry-deposition setup is presented that allows underwater reconstitution of silts, sands, and their mixtures, yielding high-quality uniform specimens. Systematic uniformity checks, which are mandatory to avoid segregation of silty materials, are described. A detailed analysis of typical errors affecting initial void ratio evaluation is also presented to ensure that comparisons between different methods are done with the highest degree of confidence possible.

Journal article

Solans D, Kontoe S, Zdravkovic L, 2023, Impact of foundation layer characteristics on the seismic response of a tailings dam, 10th European Conference on Numerical Methods in Geotechnical Engineering, Publisher: International Society for Soil Mechanics and Geotechnical Engineering

The foundation layer thickness and stiffness impact the site response by influencing the fundamental frequenciesand vibration modes in soil structure interaction (SSI) problems. From a practical perspective, the geotechnical characterisation of earthfill dams is typically focused on the borrow materials comprising the dam, while the foundation materials are often under-characterised, with the depth to the bedrock commonly only approximately estimated. In the seismic response of dams, these unknowns may also impact the deformation patterns affecting the overall stability of the dam. A back-analysis of seismic recorded data for an existing tailings sand dam is performed, to determine the thickness and stiffness of the soil foundation layer byfinite element analysis. A cyclic non-linear model (CNL) is employed in the Finite Element analyses which consider different depths to bedrock and soil stiffness profiles. The results suggest satisfactory agreement with the recorded data in terms of acceleration response spectra and amplification ratios and highlight the impact of the foundation layer characteristics on the overall dam response.

Conference paper

Pedone G, Kontoe S, Zdravkovic L, Jardine R, Potts Det al., 2023, A sensitivity study on the mechanical properties of interface elements adopted in finite element analyses to simulate the interaction between soil and laterally loaded piles, 10th European Conference on Numerical Methods in Geotechnical Engineering, Publisher: International Society for Soil Mechanics and Geotechnical Engineering

An increasing number of offshore energy structures have been built recently on driven piles, ranging from jack-et piles with typical length-to-diameter (L/D) ratios of 10-40 to monopiles with far lower L/D ratios. The load-displacementbehaviour of these foundations can be investigated by means of Finite Element (FE) analyses, for instance following the designmethodology developed by the PISA Joint Industry Project (JIP). A challenging aspect of the modelling, for piles loaded eitheraxially or laterally, is the simulation of the behaviour at the soil-pile interface with the adoption of suitable formulations for theinterface elements and with representative mechanical properties. This paper presents a sensitivity study conducted on both theelastic and plastic properties of interface elements adopted in FE analyses of laterally loaded piles driven in chalk. The studybenefited from the extensive field and laboratory test results collected during the ALPACA JIP and the corresponding piletests. The aim of the paper is to provide guidance for numerical modelling on the selection of the most appropriate mechanicalproperties of interface elements to be used in the analyses of soil-pile interaction under lateral loading.

Conference paper

Koronides M, Kontoe S, Zdravkovic L, Vratsikidis A, Pitilakis D, Anastasiadis A, Potts Det al., 2023, Numerical simulation of soil-structure interaction experiments on shallow founded structures for different mass configurations, 10th European Conference on Numerical Methods in Geotechnical Engineering, Publisher: International Society for Soil Mechanics and Geotechnical Engineering

Soil-Structure Interaction (SSI) phenomena and foundation rocking can modify the structural response signifi-cantly with respect to the response predicted adopting the fixed-base assumption. The importance of SSI and rocking depends,among other factors, on the structural mass and the distribution of static stresses at the soil-foundation interface. Within thiscontext, an experimental campaign was carried out aiming to investigate the SSI effects on the response of a 3m x 3m x 5m steel-framed structure. The prototype structure, called EUROPROTEAS, was founded on a shallow footing at the well-characterisedEuroseistest site, while its mass was either 18Mgr or 9Mgr. The present study simulates free vibration experiments, placingparticular emphasis on soil nonlinearity and soil-foundation interface. A novel approach to simulate gaps at the soil-foundationinterface, foundation rocking and to manipulate interface stresses under static conditions is presented. The three aspects areshown to significantly affect the response, while they are found to be more important for the lighter structure.

Conference paper

Cui W, Wu X, Potts DM, Zdravkovic Let al., 2023, Nonlocal strain regularisation for critical state models with volumetric hardening, Computers and Geotechnics, Vol: 157, Pages: 1-10, ISSN: 0266-352X

The finite element (FE) method may suffer from numerical instability and mesh dependency when modelling the formation of shear bands using strain-softening constitutive models. Nonlocal methods have been shown to be capable of avoiding these numerical issues effectively. This paper proposes a novel generic algorithm for incorporating existing nonlocal methods into the FE formulation of elasto-plastic constitutive models with volumetric hardening laws. Using the example of the modified Cam Clay (MCC) model this paper shows that instabilities are inevitable if the nonlocal plastic volumetric strains are directly used to update the hardening parameter. The paper further proposes a robust regularisation algorithm to overcome this issue. This algorithm has been implemented into a bespoke FE code and its capability in significantly reducing mesh dependency while maintaining numerical stability is verified through a series of numerical analyses of biaxial compression tests for highly overconsolidated clays. The performance of various existing nonlocal methods is also critically assessed.

Journal article

Pedone G, Zdravkovic L, Potts D, Tsiampousi Aet al., 2023, Numerical modelling of unsaturated MX-80 bentonite subjected to two different hydration paths and subsequent loading to high-pressures, 8th International Conference on Unsaturated Soils

Conference paper

Pedone G, Kontoe S, Zdravkovic L, Jardine RJ, Vinck K, Liu Tet al., 2023, Numerical modelling of laterally loaded piles driven in low-to-medium density fractured chalk, Computers and Geotechnics, Vol: 156, Pages: 1-18, ISSN: 0266-352X

Chalk’s sensitive, variable nature poses difficulties for foundation designers. It can present as weak rock and yet be de-structured to very weak putty by dynamic or high-pressure loading. The development of multiple offshore wind farms at north European chalk sites led to the recent ALPACA Joint Industry Programme, which undertook intensive material characterisation and large-scale field testing at St Nicholas at Wade (SNW), Kent, UK to capture and better understand the behaviour of piles driven in fractured low-to-medium density chalk. Noting that lateral loading response is a vital design concern for monopile and jacket supported structures, this paper focuses on 3D Finite Element (FE) modelling of ALPACA’s monotonic lateral loading field tests on open-ended driven tubular steel piles. The brittle chalk is modelled with a strain-softening Mohr-Coulomb model combined with nonlocal regularisation, calibrated meticulously against the ALPACA characterisation dataset. A second, simpler modelling approach, adopting a perfectly-plastic Mohr-Coulomb model, is also explored as a simplified practical alternative. Both approaches can match field lateral capacity and bending moment distributions, after taking due account of pile installation and chalk fracturing effects. The analyses indicate how robust, accurate and cost-effective lateral loading design may be approached for low-to-medium density fractured chalks.

Journal article

Petalas AL, Tsiampousi A, Zdravkovic L, Potts DMet al., 2022, Numerical investigation of the performance of engineered barriers in controlling stormwater runoff, Geomechanics for Energy and the Environment, Vol: 32, Pages: 1-15, ISSN: 2352-3808

In this paper, 2-dimensional, hydro-mechanically coupled finite element analyses are conducted to assess the performance of an engineered barrier, constructed from natural geomaterials, aimed at reducing flood risk in urban environments. The barrier consists of an unsaturated compacted soil layer with water holding properties and a drainage layer of a coarse granular material, that acts as a capillary break, and is constructed on top of the natural soil, in this case London clay. The barrier is vegetated so that its water storage capacity is renewed after each rainfall event. Sophisticated boundary conditions are used to simulate the effect of precipitation and evapotranspiration. The evolution of the rainfall infiltration and runoff rate is simulated both for a treated soil column with an engineered barrier and an untreated one consisting solely of in-situ London Clay. The percolation rate of rainfall water from the bottom of the barrier is also estimated. This comparison highlights the effectiveness of the engineered barrier in reducing the risk of fast flooding, in preventing excessive deformations and in protecting underground infrastructure during wetting and drying cycles. The effect of the hydraulic properties and geometry of the barrier is investigated by means of an extensive parametric analysis. Finally, recommendations for the design of barrier systems are made.

Journal article

Solans D, Kontoe S, Zdravkovic L, 2022, Comparison of the monotonic and cyclic response of tailings sands with a reference natural sand, 4rth International Conference on Performance-based Design in Earthquake Geotechnical Engineering, Publisher: Springer

This article considers the monotonic and cyclic behaviour of a tailings sand material, tested over a wide range of confining pressures and relative densities. The collated experimental data are used to interpret the behaviour of this material in the framework of Critical State Soil Mechanics (CSSM) and to calibrate an advanced bounding surface plasticity model. The response of this man-made material is then contrasted, within the same framework, to that of Toyoura sand, which is a well-characterised reference natural sand.This process aims to identify the principal behavioural differences between the two types of geo-materials and the implications that these may have on the calibration process of an advanced constitutive model. Ultimately, the process also supports the numerical modelling of Tailings Storage Facilities under both monotonic and cyclic/earthquake loading.

Conference paper

Koronides M, Kontoe S, Zdravkovic L, Vratsikidis A, Pitilakis D, Anastasiadis A, Potts Det al., 2022, Numerical simulation of real-scale vibration experiments of a steel frame structure on a shallow foundation, 4rth International Conference on Performance-based Design in Earthquake Geotechnical Engineering

Conference paper

Tkahashi H, Zdravkovic L, Tsiampousi A, Mori Net al., 2022, Destabilisation of seawall ground by ocean waves, Geotechnique: international journal of soil mechanics, ISSN: 0016-8505

Seawalls are constructed by covering and protecting the sloping seashore ground with concrete plates or blocks. Their purpose is to sustain high waves induced by strong winds and prevent ground erosion, but they often collapse,mobilising different modes of failure, including that of the ground. Nonetheless, limited research has been conducted on ground failure caused by high waves. In this study, a series of novel centrifuge model tests was first conducted to investigate the failure mechanisms of seawalls due to wave propagation, focusing on the failure of the ground. Finite element analyses were subsequently conducted to explore the failures observed in the model tests and to provide further insight as to the state of the ground leading to failure. Two failure modes were demonstrated to prevail: floating of the covering panel and sliding failure of the ground. Additionally, of the possible causes of failure, the following three were identified in the current study: increased unit weight and reduced suction from wetting; enhanced seepageforce under the panel and around the toe block during backwash; water pressure on the back of the panel and the landward side of the toe block during backwash.

Journal article

Sailer E, Taborda D, Zdravkovic L, Potts DMet al., 2022, A novel method for designing thermo-active retaining walls using two dimensional analyses, Proceedings of the Institution of Civil Engineers: Geotechnical Engineering, Vol: 175, Pages: 289-310, ISSN: 1353-2618

Thermo-active retaining walls are geotechnical structures employed as heat exchangers to provide low carbon dioxide heating and cooling to buildings. To assess the thermo-mechanical response of such structures, finite-element (FE) analyses are typically carried out. Due to the presence of heat exchanger pipes, the temperature distribution along the width of the wall is not uniform, implying that these problems are three-dimensional (3D) in nature. However, performing 3D FE analyses including elements to model the heat exchanger pipes to simulate the advective conductive heat transfer as well as thermo-hydro-mechanical coupling to reproduce the non-isothermal soil response accurately requires considerable computational effort. In this work, a novel approach to simulate thermo-active walls in 2D analyses was developed, which requires the sole use of thermal boundary conditions. This approach was found to reproduce average wall behaviour computed in 3D to a high degree of accuracy for numerous wall geometries, a wide range of thermal properties of soil and concrete, and different thermal boundary conditions along the exposed face of the wall. In addition, out-of-plane effects recorded in 3D analyses were assessed and an accurate simplified procedure to account for these when performing 2D analyses was developed.

Journal article

Koronides M, Kontoe S, Zdravkovic L, Vratsikidis A, Pitilakis D, Potts D, Anastasiadis Aet al., 2022, 'Numerical simulations of field soil-structure interaction experiments on a shallow founded steel frame structure, 3rd international Conference on Natural Hazards & Infrastucture

Conference paper

Pedone G, Tsiampousi A, Cotecchia F, Zdravkovic Let al., 2022, Coupled hydro-mechanical modelling of soil-vegetation-atmosphere interaction in natural clay slopes, Canadian Geotechnical Journal, Vol: 59, Pages: 272-290, ISSN: 0008-3674

Soil-vegetation-atmosphere interaction is long known to induce significant pore pressure variations at shallow depths and associated superficial slope movements. Recent findings suggest that the effect of this interaction may also extend to large depths in natural clay slopes. Multiple examples of weather-induced deep landslide mechanisms can be found in the Southern Apennines (Italy), where slopes are often formed of fissured clays. The relationship between the activity of these landslides and the hydro-mechanical processes due to soil-vegetation-atmosphere interaction was investigated herein by means of a two-dimensional coupled hydro-mechanical finite element analysis. A constitutive model capable of simulating the behaviour of highly overconsolidated clays, in both saturated and unsaturated states, was adopted in the analysis, in conjunction with a boundary condition capable of reproducing the combined effects of rainfall infiltration, evapo-transpiration and run-off. The results of the analysis corroborate the connection between weather conditions, pore pressure variations and slope movements in natural clay slopes. The importance of reproducing adequately the geological history of a natural slope in order to define its current state is also demonstrated.

Journal article

Cui W, Potts DM, Pedro AMG, Zdravkovic Let al., 2021, Numerical assessment of the effects of end-restraints and a pre-existing fissure on the interpretation of triaxial tests on stiff clays, Geotechnique: international journal of soil mechanics, Vol: 71, Pages: 765-780, ISSN: 0016-8505

Conventional laboratory triaxial tests apply axisymmetric boundary conditions to a cylindrical sample which has an axisymmetric geometry. For a homogeneous sample this implies that the deformed shape of the sample should maintain an axisymmetric geometry during the test. Consequently, the sample should deform in a barrelling mode and if slip planes develop they should define a cup and cone-like failure surface. However, in many triaxial tests such behaviour is not observed, especially as failure is approached when a planar slip surface develops. Such a deformation mode is not axisymmetric. One reason for this behaviour is that a fissure pre-exists in the sample. Employing hydro-mechanically coupled three-dimensional finite-element analyses, this paper investigates the influence of a single fissure in a triaxial sample of stiff clay on its behaviour throughout the test, focusing on the fissure position, orientation, strength and stiffness, in conjunction with the sample's end-restraints (rough or smooth). The effects are quantified in terms of the sample's overall stiffness and strength, indicating that the presence of a fissure can affect the very small strain stiffness, and that it has a significant effect on the strength of the sample, demonstrating that the conventional methods used to interpret laboratory tests may give unconservative results. The results also show a significant effect of the conditions at the top and bottom surfaces of the sample, where in particular the lateral restraint and rough ends introduce ‘bending’ in the sample.

Journal article

Zdravković L, Potts DM, Taborda DMG, 2021, Integrating laboratory and field testing into advanced geotechnical design, Geomechanics for Energy and the Environment, Vol: 27, Pages: 1-21, ISSN: 2352-3808

Contemporary geotechnical design often requires the use of advanced numerical analysis, if it is to take account of the complex nature of many geotechnical problems. One crucial aspect of such analyses is the realistic representation of the facets of soil behaviour that are dominant in any given problem, which in turn requires a careful selection of an appropriate constitutive model and derivation of model parameters from the available, and often disparate, experimental data. This paper uses the authors’ experience of advanced numerical analysis and constitutive modelling to emphasise the importance of close integration of the process involved with interpreting experimental data with the process of selecting and calibrating advanced constitutive models, in successfully predicting the response of geotechnical structures.

Journal article

Gawecka K, Cui W, Taborda D, Potts D, Zdravkovic L, Loukas Aet al., 2021, Predictive modelling of thermo-active tunnels in London Clay, Geotechnique: international journal of soil mechanics, Vol: 71, Pages: 735-748, ISSN: 0016-8505

Thermo-active structures are underground facilities which enable the exchange of thermal energy between the ground and the overlying buildings, thus providing renewable means of space heating and cooling. Although this technology is becoming increasingly popular, the behaviour of geotechnical structures under additional thermal loading is still not fully understood. This paper focuses on the use of underground tunnels as thermo-active structures and explains their behaviour through a series of finite element analyses based on an existing case study of isothermal tunnels in London Clay. The bespoke finite element codeI CFEP is adopted which is capable of simulating the fully coupled thermo-hydro-mechanical behaviour of porous materials. The complex coupled interactions between the tunnel and the surrounding soil are explored bycomparing results from selected types of coupledand uncoupled simulations. It is demonstratedthat: (1) the thermally-induceddeformation of the tunnel and the ground are more critical design aspects than the thermally-induced forces in the tunnel lining, and (2) the modelling approach in terms of the type of analysis, as well as the assumed permeability of the tunnel lining, have a significant effect on the computed tunnel response and,hence, must be chosen carefully

Journal article

Potts DM, Cui W, Zdravković L, 2021, A coupled THM finite element formulation for unsaturated soils and a strategy for its nonlinear solution, Computers and Geotechnics, Vol: 136, ISSN: 0266-352X

This paper presents a coupled thermo-hydro-mechanical (THM) finite element (FE) formulation which is capable of accounting for the effects of temperature change on the behaviour of unsaturated soils. Both vapour flow and density variation are taken into account in the development of this formulation. The full derivation procedure is provided and the adopted assumptions are stated and explained. To improve the efficiency of the nonlinear solution process while maintaining the accuracy of the prediction, a novel approach for determining iterative corrections when modelling coupled transient problems with the Newton-Raphson algorithm is established and presented here. The performance of the proposed FE formulation and of the new strategy for iterative corrections in a nonlinear solver is subsequently demonstrated and verified by simulations of laboratory experiments on unsaturated compacted bentonite, showing good agreement between the numerical and experimental results.

Journal article

Sailer E, Taborda DMG, Zdravkovic L, Potts DM, Cui Wet al., 2021, Thermo-hydro-mechanical interactions in porous media: implications on thermo-active retaining walls, Computers and Geotechnics, Vol: 135, Pages: 1-16, ISSN: 0266-352X

Thermo-active structures exchange heat with the ground to provide thermal energy to buildings. Consequently, the ground is subjected to changes in temperature, inducing thermo-hydro-mechanical (THM) interactions within the soil. To provide insights into the origin and manifestations of the main mechanisms taking place in complex fully THM-coupled finite element (FE) analyses, simple, one-dimensional problems are firstly analysed in this paper and compared to analytical expressions developed for determining thermally-induced excess pore water pressures in undrained problems with different displacement restraints. Subsequently, various dimensionless parameters are established to evaluate the impact of varying ground properties on the observed THM interactions and their evolution with time. Finally, the findings from simple one-dimensional problems are verified in the context of THM modelling of thermo-active retaining walls, where the structural response of walls is shown to be highly transient and influenced by different phenomena prevailing over different periods involving thermal expansion of soils, volumetric deformations due to pore water generation and dissipation, and interactions with mechanical boundary conditions. The results also highlight the importance of performing fully coupled THM analyses and of a correct estimation of the hydraulic and thermal properties to guarantee a safe design of thermo-active structures.

Journal article

Petalas A, Tsiampousi A, Zdravkovic L, Potts Det al., 2021, Numerical investigation of the performance of engineered barriers in reducing flood risk, 3rd Pan-American Conference on Unsaturated Soils

Conference paper

Zdravkovic L, Cui W, Gawecka K, Liu RYW, Potts DM, Sailer E, Taborda Det al., 2021, Numerical Modelling of Thermo-Active Piles, PIling 2020

Conference paper

Zhou D, Zdravkovic L, 2021, Numerical analysis of Double-O-Tube shield tunneling in Shanghai, 10th International Symposium on Geotechnical Aspects of Underground Construction in Soft Ground (IS-Cambridge), Publisher: ROUTLEDGE, Pages: 475-481

Conference paper

Zdravkovic L, Taborda DMG, Potts DM, 2020, Effect of interface conditions on the response of laterally loaded monopiles in sand, 4th International Symposium on Frontiers in Offshore Geotechnics

Conference paper

Byrne BW, McAdam RA, Beuckelaers WJAP, Burd HJ, Gavin K, Houlsby GT, Igoe DJP, Jardine RJ, Martin CM, Potts DM, Taborda DMG, Zdravkovic Let al., 2020, Cyclic laterally loaded medium scale field pile testing for the PISA project, 4th International Symposium on Frontiers in Offshore Geotechnics

Conference paper

Sailer E, Taborda D, Zdravkovic L, Potts Det al., 2020, Simplified methods for designing thermo-active retaining walls, 2nd International Conference on Energy Geotechnics (ICEGT2020), Publisher: EDP Sciences, Pages: 06011-06011, ISSN: 2267-1242

Thermo-active retaining structures are geotechnical structures employed to provide thermal energy to buildings for space heating and cooling through heat exchanger pipes embedded within the concrete structure. Consequently, the design of these structures needs to consider both the long-term energy efficiency as well as the thermo-mechanical response in terms of stability and serviceability. Transient finite element analyses can be carried out to evaluate the behaviour of thermo-active walls, where the heat exchanger pipes are explicitly modelled, thus requiring three-dimensional (3D) analyses. However, performing long-term 3D finite element analyses is computationally expensive. For this reason, in this study, new approaches are presented that allow the thermal or thermo-mechanical design of thermo-active walls to be carried out by performing two-dimensional (2D) plane strain analyses. Two methods, which are based on different design criteria, are proposed and their performance in replicating the three-dimensional behaviour is assessed. Furthermore, the factors affecting the 2D approximations for the two modelling approaches are evaluated, where particular emphasis is given to the influence of the simulated boundary condition along the exposed face of the retaining wall.

Conference paper

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://wlsprd.imperial.ac.uk:80/respub/WEB-INF/jsp/search-html.jsp Request URI: /respub/WEB-INF/jsp/search-html.jsp Query String: respub-action=search.html&id=00157663&limit=30&person=true