Thesis Work - Stability assessment of slender reinforced concrete walls

The owners of the Forsmark and Ringhals nuclear power plants in Sweden have taken a directional decision to extend the operating lifetime of the plants' reactors from 60 to 80 years. An in-depth investigation phase awaits, which will include more detailed  calculations and analysis before investment decision can be made. To extend the operating time, investments are necessary to replace or renovate systems and components, including plant buildings and other infrastructure.

The objective of this thesis is to study how to ensure a safe and sustainable operational lifetime extension of plant buildings and other infrastructure.

Subject:

Stability assessment of slender reinforced concrete walls using multiple analysis tools and EC2 standard generations. Potential analysis methods of interest are:

• Simplified method based on nominal curvature
• Second order linear elastic analysis method based on reduced stiffness value.
• A general fully non-linear analysis method

A study case will be provided. 

Goal:

The following objectives can be defined:

1. To compare the different analysis methods in terms of result and ease of implementation in commercial finite element analysis programs.
2. To evaluate the effect of concrete creep, and study how the effect of creep can be evaluated for existing structures and temporary design situations. 
3. Discuss differences between the EC2:2005 and EC2:2023

This thesis is suitable for one or two students.

The work will be conducted in collaboration with Vattenfall Power Solutions (VPS), which aims to support Vattenfall’s partners in delivering safe and sustainable energy solutions from both a near-term and long-term perspective.

We are looking for a student or students who want to work towards fossil freedom and who are about to graduate from their academic studies. You are also someone who identifies with our principles: Active, Open, Positive, and Safety.

• Education – Applicants should be in the final phase of a Master's degree in Civil engineering, Mechanical Engineering or equivalent
• Scope – 30 credits
• Proficient written and verbal communication skills in English. Knowledge of Swedish is a plus.

• Start date: 2026-01-19 or by agreement.
• Location: Solna
• Application – one file containing your CV and a copy of your transcripts.
• Application deadline: 2025-10-26.
• Contact person and supervisor at Vattenfall: Cristian Sabau, Cristian.sabau@vattenfall.com, +46 70-260 31 23

Diversity and Inclusion – In Everything We Do

We are convinced that heterogeneous teams can outperform homogeneous ones. But we can only unlock the power of diversity when everyone feels included. Read more about our important work on diversity and inclusion at https://careers.vattenfall.com/se/sv/jobba-med-oss/mangfald-inkludering.

About Vattenfall

At Vattenfall, we are determined to enable fossil freedom. To succeed, we must first become fully fossil-free ourselves as one of Europe’s largest energy companies. But that is not enough. To contribute to a fossil-free society, we need to do more than just focus on sustainable energy production.

We believe that enabling fossil freedom requires us to address the challenge from a broader perspective than merely producing energy sustainably.

Join us on the journey towards fossil freedom.

As Vattenfall is part of Sweden’s critical infrastructure, many of our roles are security-classified. This means that, if this position is security-classified, final candidates may be subject to a special security clearance in accordance with the Security Protection Act.

To enable the fossil freedom that drives society forward – this is our purpose. We are looking for talented students who want to help us on our journey towards fossil freedom. By writing a thesis at Vattenfall, you will have a unique opportunity to contribute to our purpose.