Publications associées à Unified stress framework for modelling unsaturated subsoil behaviour

A novel fatigue life prediction methodology based on energy dissipation in viscoelastic materials, synergistic effects of stress level, stress ratio, and temperature

Thomas Keller, Abdolvahid Movahedirad, Lulu Liu

This work introduces a new methodology to predict the fatigue life of viscoelastic materials by considering the creep effect on fatigue behavior under the concurrent effects of stress level, stress ratio, and temperature. The model established based on the ...

2024

Adolescent Stress-Induced Ventral Hippocampus Redox Dysregulation Underlies Behavioral Deficits and Excitatory/Inhibitory Imbalance Related to Schizophrenia

Maria del Carmen Sandi Perez, Dogukan Hazar Ülgen, Thamyris Silva

Background and hypothesis: Redox dysregulation has been proposed as a convergent point of childhood trauma and the emergence of psychiatric disorders, such as schizophrenia (SCZ). A critical region particularly vulnerable to environmental insults during ad ...

2024

Experimental and analytical investigation of shear-reinforced concrete and dowel action

Marko Pejatovic

Codes of practice can be overly conservative, particularly for the shear resistance of reinforced concrete beams with shear reinforcement when large loads act close to supports. This thesis addresses the topic by proposing a refined design approach based o ...

EPFL2024

Frictional weakening leads to unconventional singularities during dynamic rupture propagation

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Federica Paglialunga, Mathias Alexandre David Lebihain

Earthquakes i.e. frictional ruptures, are commonly described by singular solutions of shear crack motions. These solutions assume a square root singularity order around the rupture tip and a constant shear stress value behind it, implying scale-independent ...

2024

Influence of fiber orientation on the tensile behavior of UHPFRC and reinforced UHPFRC under static and fatigue loadings

Jian Zhan

Ultra-high performance fiber reinforced cementitious composite (UHPFRC) is a modern class of cementitious building materials. Because of its superior mechanical properties and durability, it is increasingly used globally to rehabilitate, strengthen and mod ...

EPFL2024

Pore-pressure coefficients for unsaturated soils: generalized effective stress approach

Lyesse Laloui, Alessio Ferrari, Angelica Tuttolomondo

Geotechnical problems with total stress changes occurring rapidly relative to the soil consolidation time can be conveniently addressed using an effective stress-based approach. For saturated states, analytical formulations of pore-pressure coefficients ad ...

CANADIAN SCIENCE PUBLISHING2023

'connEcted caesarean section': creating a virtual link between MOthers and their infanTs to ImprOve maternal childbirth experieNce - study protocol for a PILOT trial (e-motion-pilot)

Sandra Maria Marcadent, Karine Lepigeon, Fiona Corbaz, David Desseauve

IntroductionOne-third of mothers rate their childbirth as traumatic. The prevalence of childbirth-related post-traumatic stress disorder (CB-PTSD) is 4.7%. Skin-to-skin contact is a protective factor against CB-PTSD. However, during a caesarean section (CS ...

BMJ PUBLISHING GROUP2023

Psychosomatic response to acute emotional stress in healthy students

Adriana Arza Valdes

The multidimensionality of the stress response has shown the complexity of this phenomenon and therefore the impossibility of finding a unique biomarker among the physiological variables related to stress. An experimental study was designed and performed t ...

FRONTIERS MEDIA SA2023

A fully-coupled highly-parallelized geomechanical simulator for assessing induced seismicity

Jean-François Molinari, Guillaume Anciaux, Nicolas Richart, Brice Tanguy Alphonse Lecampion, Emil Gallyamov

Induced seismicity caused by anthropogenic modification of the subsurface effective stress state has been observed in a number of industrial applications -- from hydrocarbon extraction (e.g., Groningen [1]), drilling waste-water disposal (e.g., [2]) to the ...

2023

Single-Well Pore Pressure Preconditioning for Enhanced Geothermal System Stimulation

Marie Estelle Solange Violay, Barnaby Padraig Fryer, Mathias Alexandre David Lebihain

The stress state is an important parameter in terms of both earthquake nucleation and rupture. Here, a new stimulation technique is proposed for Enhanced Geothermal Systems (EGSs), which have previously been burdened with a number of high-profile incidence ...

2023

Transcriptomic analysis reveals mitochondrial pathways associated with distinct adolescent behavioral phenotypes and stress response

Maria del Carmen Sandi Perez, Dogukan Hazar Ülgen, Thamyris Silva

Adolescent individuals exhibit great variability in cortical dynamics and behavioral outcomes. The developing adolescent brain is highly sensitive to social experiences and environmental insults, influencing how personality traits emerge. A distinct patter ...

2023

Drained Clay-Pipe Interface Resistance at Low Normal Stresses and Elevated Temperatures

Roba Houhou

Offshore pipelines that transport hydrocarbons under high pressure and high temperature are usually thermally insulated to maintain an elevated temperature and prevent any heat loss to the surroundings. However, the temperatures at the outer-wall of the pi ...

AMER SOC CIVIL ENGINEERS2023

Microscopic Digital Image Correlation Analysis of Strain Distributions in Stainless Steel 316L Induced by Multiaxial Cyclic Loading

Elif Cansu Kursun

Fatigue damage in materials results in localized strain at the microstructural level. In many engineering components of the cooling circuits of nuclear power plants, where austenitic steels are used, the material experiences multiaxial cyclic loading, eith ...

EPFL2023

Bounding the localized to ductile transition in porous rocks: implications for geo-reservoirs

Marie Estelle Solange Violay, Gabriel Gérard Dominique Meyer

Porous rocks have long been the focus of intense research driven by their importance in our society as host to our most essential resources (oil, gas, water, geothermal energy, etc), yet their rheology remains poorly understood. With increasing depth, poro ...

2023

Influence of pore-scale heterogeneity on the precipitation patterns in Microbially Induced Calcite Precipitation (MICP)

Ariadni Elmaloglou

The principle of tailoring material properties to improve the mechanical behaviour of soils through compaction or cement grouting dates to the 60s. The increasing trends of urbanization worldwide require new solutions for the development of resilient and s ...

EPFL2023

Crack tip kinematics reveal the process zone structure in brittle fracture

John Martin Kolinski, Chenzhuo Li, Xinyue Wei

When brittle hydrogels fail, several mechanisms conspire to alter the state of stress near the tip of a crack, and it is challenging to identify which mechanism is dominant. In the fracture of brittle solids, a sufficient far-field stress results in the co ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Elastic limit tensile stress of UHPFRC: Method of determination and effect of fiber orientation

Eugen Brühwiler, Emmanuel Denarié, Jian Zhan

This paper discusses the influence of fiber orientation on elastic limit tensile stress of ultra-high performance fiber reinforced cementitious composites (UHPFRC). An original model relating elastic limit tensile stress to fiber orientation is proposed, a ...

2023

Three-dimensional stress state during dynamic shear rupture propagation along frictional interfaces in elastic plates

Jean-François Molinari, Roozbeh Rezakhani

The state of stress in plates, where one geometric dimensions is much smaller than the others, is often assumed to be of plane stress. This assumption is justified by the fact that the out-of-plane stress components are zero on the free-surfaces of a plate ...

ELSEVIER2022

Opposite effects of stress on effortful motivation in high and low anxiety are mediated by CRHR1 in the VTA

Maria del Carmen Sandi Perez, Olivia Zanoletti, Jocelin Grosse, Marie-Isabelle Guillot de Suduiraut, Ioannis Zalachoras, Simone Astori, Mandy Meijer

Individuals frequently differ in their behavioral and cognitive responses to stress. However, whether motivation is differently affected by acute stress in different individuals remains to be established. By exploiting natural variation in trait anxiety in ...

2022

Negative Associations of Stress and Anxiety Levels With Cytotoxic and Regulatory Natural Killer Cell Frequency in Chronic Tinnitus

Patrick Karl Alois Neff

BackgroundDepression and anxiety are known to be associated with stress-induced changes in the immune system. Bothersome tinnitus can be related to stress and often co-occurs with depression and anxiety. This study investigates associations of psychologica ...

Frontiers Media2022