Complex systems and circular cities
The circularity of the built environment can be analyzed through different levels or scales, from the micro-level (i.e., building materials and products) to the macro-level (i.e., neighborhoods and cities). The larger the scale, the more complex and interdisciplinary the systems involved. Cities are extremely complex systems where social, ecological, and technical dimensions are deeply interconnected and affect each other in both desirable and undesirable ways. Therefore, understanding cities' transdisciplinary and complex nature is key to advancing urban sustainability and resilience agendas. At the same time, there is a need to understand CE as a complex system.
During my postdoc with Dr. Melissa Bilec, I conducted a systematic literature review and thematic analysis to identify case studies of CE initiatives in different cities around the globe that have considered the systemic dimensions of CE and their interconnections and iterations. These include governmental, economic, environmental, technological, societal, and behavioral dimensions. The selected case studies informed a conceptual model that illustrates CE's functions in an urban setting (see figure). This work was aimed at helping policymakers, designers, and researchers to better understand how CE initiatives function in an urban setting and to ethically design changes in the system to achieve circularity goals. The results suggested that meaningful stakeholder engagement is key to co-designing ethical CE interventions in the built environment.
More recently, during my postdoc at the University of Pittsburgh and after similar studies were published in European countries, I conducted a thematic analysis in the same interview data and quantified the barriers and enablers according to main themes. That allowed me to compare my results to the recent European studies (Figure 4). Although the share of technical and economic barriers was similar to those found in Europe, I found more educational and cultural barriers in the US, while European studies found a larger share of regulatory and technological barriers. Finally, I developed a framework with barriers and enablers for circular building design and the role of different stakeholders in enabling circular built environments. This work will help establish research and policy agendas and form new partnerships within the US construction sector.