The following is an excerpt.

Andria Antoniou was to leave Grenoble to start working as a postdoc at SFI CASA on 16 March, but Covid-19 locked her up in France.

«Unfortunately, I do not have any insights as to how long I have to stay in France», Andria Antoniou tells in an email interview.
Since the second week of March, people in France needed a certificate to go out for groceries or physical exercise. They were only allowed to move within a radius of 1 kilometre from their homes, and cannot stay outdoor for more than one  hour. After 11th May, new rules came into effect. Then, people were allowed to move around without any certificate – within a radius of 100 kilometres. On the question of when people are allowed to travel out of France there is not yet official information.
«At the beginning, the entire first month was difficult for me physically and mentally. But now I am used to spending my evenings and weekends on the couch watching films, drawing or playing music with my ukulele», the new postdoc at CASA tells.

CONCRETE SUBJECTED TO HIGH-INTENSITY LOADING

Her primary field of interest and expertise is in numerical modelling of concrete structures; more specifically, the development of models that describe damage of concrete under extreme loading conditions. In Trondheim, Andria Antoniou is to work closely with Professor Tore Børvik and Researcher Martin Kristoffersen. The project is entitled «Development of test regimes and numerical procedures for concrete subjected to high-intensity loading».
The position caught her interest because it is directly related to the field of her PhD. On top of that, the pioneering research conducted at CASA attracted her as well.

STUDIES IN CYPRUS, GREECE, FRANCE AND ITALY

 Andria Antoniou is from Cyprus. She studied Civil and Environmental Engineering at the University of Cyprus. During the 3rd year of her BSc she attended at the National Technical University of Athens.
She obtained a master’s degree in Earthquake Engineering as an Erasmus Mundus student, both at the University of Grenoble I-Joseph Fourier in France and the Institute for Advanced Study of the University of Pavia in Italy. She says her MSc studies amplified her knowledge in Structural Analysis and Capacity Design philosophy applying force-based, displacement-based and performance-based seismic design approaches.

A MODEL ABLE TO PREDICT ADVANCED DAMAGE STATES

In 2018 she earned her PhD in impact engineering. Her dissertation is entitled «Discrete element modelling of concrete structures under impact». Her project was a collaboration between the laboratory 3S-R (University Grenoble Alpes) and the research centre of EDF R&D (Paris-Saclay).
«The objective of my PhD project was the development of a numerical tool in Europlexus. Europlexus is a fast dynamics software, capable of modelling concrete infrastructures subjected to severe dynamic loadings. This study established a 3D discrete element model able to predict advanced damage states and to obtain realistic micro-cracks and material fragments thanks to its discrete nature», she explains.

A PART OF THE SIMLAB- FAMILY

 She had been working for 6 months as a postdoctoral researcher at University Grenoble Alpes when she applied for the position at CASA. Earlier this winter, she received an invitation to visit Trondheim for a meeting with Professor Magnus Langseth, Professor Tore Børvik and Dr Martin Kristoffersen. Here, she also met with some of the other employees at SFI CASA.
«Everyone was amicable and welcoming. I felt immediately at home. When I received the job proposal from SFI CASA I did not doubt to sign the contract and become a part of this scientific family», she says. «I would also like to mention that I am grateful for all the efforts from the HR team at NTNU who finally found a solution to establish a remote contract during this challenging period of COVID-19».

COMPARING FE- AND DE METHODS

 There is a long list of working tasks waiting for her in Trondheim. She will simulate some pull-out test of reinforced concrete employing Finite Element Method (FEM) and Discrete Element Method (DEM). After that, she will compare the two methods and evaluate their accuracy.
Further, she would like to implement the constitutive model of the DEM that she extended during her PhD, with a detailed steel-concrete bond model. As a postdoctoral researcher, she will also work on an experimental campaign that includes impact and blast experiments on concrete components. The aim is to establish an elaborate database of concrete mechanical properties. Such a base will consistently assess the influence of each concrete constituent and their combination.
Besides, she will extend the previous DEM into a mesoscale reliable numerical tool. This task involves a constitutive model of concrete composition. To validate and apply mathematical models on real scale infrastructure is also on her to-do list.

CURIOSITY ABOUT CONCRETE

«Why did the topic of damage to concrete structures under severe impacts catch your interest from the start»?
«The initial factor was curiosity, born during the first years of my BSc degree. Because, in courses like dynamics of structures; the field of accidental loadings was always briefly mentioned as something that exists but never exhaustively taught. Then, during my MSc thesis, I was looking for a topic for my thesis project. I came across with the Risks, Vulnerability of Structures and Mechanical Behaviour of materials team (RV team) at the laboratory 3S-R. Damage of concrete structures is one of their primary expertise. So, finally, I was introduced to the word of accidental loading on concrete structures and evaluation of damage with accurate constitutive numerical models.

ENSURING THE SAFETY OF THE PUBLIC

«Why do we need this kind of research»?
«Unfortunately, nowadays the accidental conditions such as aircraft or missile impacts on infrastructures lead to a demand for designs to withstand high-intensity loadings. Because of the extreme severity of such loadings, it is necessary to investigate the response of the structure until almost its complete failure to assess its ultimate resistance capacity correctly ensuring the safety of the public».

MISS THE ABILITY TO MOVE FREELY AROUND

For the time being, Andria Antoniou does not have any information on for how long she has to stay in France. She explains that she, after a tough first month, began to cope.
«Before the lock-down, I was barely at home. I was working, doing some sports and meeting my friends. During the weekends I was hiking in the mountains or chilling in a park. Emotionally, it was difficult to spend the entire day at home, not being able to meet friends or to ravel back home to spend Easter with my family. Now, I can perfectly handle staying at home. But still, when the weather is good with bright sunshine, I have a bitter feeling recalling the days when we were free to move around».

Andria Antoniou will work closely with Professor Tore Børvik and Researcher Martin Kristoffersen. Here they are, discussing future plans on Zoom.