The doctoral student worked in two research groups, one in Poland and the other one in Belgium, under the supervision of two supervisors and two auxiliary supervisors. His doctoral dissertation was written in English. His research focused on the potential use of alkali-activated mortars made of by-products obtained from coal and biomass combustion as building composites.

Prof. dr hab. inż. Andrzej Garbacz was the Polish supervisor of the dissertation. His counterpart at L'Université De Liège (ULiege) was Professor Luc Courard. Dr inż. Tomasz Piotrowski and Zengfeng Zhao, PhD, were the auxiliary supervisors. The PhD committee was chaired by Professor Stephanié Lambert (ULiege), with WUT Professor dr hab. inż. Piotr Woyciechowski as co-chair at the WUT. Dr hab. inż. Izabela Hager, Professor of the Krakow University of Technology, and Professor Benoit Bissonnette of Université Laval (Quebec, Canada) were the reviewers.  

Due to the pandemic, the public defence was held online on 8 December 2020 through a special communication channel established between the research institutions. As a result of the decisions taken by the Committee at a session held behind closed doors, Professor Stephanié Lambert, on behalf of the Rector of L'Université De Liège, announced the award of a PhD degree in engineering and technology sciences to mgr. inż. Piotr Prochoń. On 12 January 2021, the Scientific Board of the Civil Engineering and Transport Discipline of the Warsaw University of Technology awarded him the Polish degree of PhD in engineering and technology sciences in the civil engineering and transport discipline.

The PhD dissertation was developed under an agreement on joint supervision (“cotutelle agreement”). Under such an agreement, research is conducted simultaneously at two universities under the joint supervision of two supervisors, one from each university. It can be done upon the request of one of the institutions, the supervisor or the PhD student. A bilateral agreement between the institutions is the minimum requirement for an international PhD to be developed. Each agreement is signed on a case-by-case basis and its terms depend on both universities, the legal systems they operate in and their collaboration needs.

The agreement leads to a doctoral degree being awarded by both universities in parallel. This makes the degree more prestigious and recognizable and also reflects the substantive input of both universities into the education process and research conducted by the young researcher.