Recent years have seen a rapid development within manufacturing technologies, easing fabrication across length scales from material architectures, to components and civil structures. As a consequence, there is now a need for novel engineering design methods that match the new manufacturing paradigm. Freeform design offers a means to leverage the advanced manufacturing possibilities. Topology optimization is a popular free-form design approach in which a formal optimization problem is posed and solved using mathematical programming. Although manufacturing has been revolutionized, there are still fabrication limitations. This talk focuses on the need for identifying the relevant behavioral and manufacturing constraints and incorporating them within the design process.

Recently, a large research focus has been on embedding the characteristics of 3D printing into topology optimization algorithms. This talk presents the first algorithm that incorporates the discrete nozzle size restrictions associated with material extrusion 3D printing processes such as fused Fused Filament Fabrication (FFF) and concrete 3D printing. The extrusion printing process consists of a nozzle that moves across the build plate and deposits the extruded material on a 2D slice of the design. If the nozzle has a discrete size, the thickness of any member must consist of a discrete number of nozzle passes. This work uses a density-based topology optimization approach in which the manufacturing constraint is implicitly embedded in the filtering operation. Design solutions are shown to fulfill the nozzle restriction constraint on several benchmark examples.

Despite the advances in construction technologies, there has been little research focused on developments and application of topology optimization to civil structures. This talk will introduce and discuss design frameworks for structural systems and components made of both timber-steel and reinforced concrete. A framework to design timber-steel trusses with minimized embodied carbon will be presented. Additionally, designs for plain and reinforced concrete beams are obtained, constructed and experimentally tested in efforts to show how topology-optimized designs can achieve performance improvements without requiring a high structural complexity.


Josephine Carstensen is an Assistant Professor in the Department Civil and Environment Engineering at MIT. She leads the top+ad research group and her research revolve around the engineering question of “how we design the structures of the future?” Her work spans from development of computational design frameworks for various structural types and design scenarios over experimental investigations that are used to inform necessary algorithmic considerations.

Dr. Carstensen has received awards for both research and teaching, including the National Science Foundation CAREER award. She received her PhD from Johns Hopkins University in 2017 and holds a B.Sc. and a M.Sc. from the Technical University of Denmark.


Open to all. Attendees external to Imperial need to register. 

Time: 13:00 for a 13:10 seminar start.