Nurturing the Next Generation of Engineers and Exploring New HSS Connections for the Future

Peer Perspective: Dr. Jason McCormick, University of Michigan

We recently spoke with Dr. Jason McCormick, Arthur F. Thurnau professor in the department of civil and environmental engineering at the University of Michigan. McCormick is also the faculty advisor for the College of Engineering’s honors program and the director of the large-scale structural engineering laboratory at the University of Michigan. Hear his insights on developing the next generation of structural engineers, designing with HSS, concrete-filled HSS and more in this edition of STI Peer Perspectives.

Q: Can you share an overview of the courses you typically teach at the University?

A: I’ve had the pleasure of teaching a wide variety of courses, from sophomore-level Statics and Dynamics to the department’s senior capstone course, which is called Professional Issues and Design, to a specialized graduate course on Passive Control of Structural Systems. The courses I teach most regularly are the senior undergraduate Design of Metal Structures course and the graduate level Plastic Analysis and Design of Frames course, both of which focus on steel systems. It’s always great to see the students’ excitement when they’re taking design-based courses and their amazement as they start to understand how systems behave, particularly beyond the elastic range.

Q: We know that you’re active in several student and professional organizations. Could you describe for us your involvement in these organizations?

A: It’s always been clear that experiential learning outside of the classroom is just as important, if not more so, than learning achieved within the classroom. This idea is what led to my willingness to become the advisor of the University of Michigan Student Steel Bridge team back in 2009. I enjoy interacting with the students and providing guidance where needed. One thing I find to be particularly important as a faculty advisor is to let the students make decisions. This way, they become comfortable with taking on leadership roles and learning how to navigate problems as individuals and as a team. The sense of accomplishment I see in the students when they work through a problem has always been a great motivator to continue my work with student organizations. Over the years, I’ve seen the diversity of the team grow with many female students taking on leadership positions, which is great to see.

My involvement with the Student Steel Bridge Competition also unexpectedly led to me taking over as chair of the National Student Steel Bridge Competition Rules Committee prior to the 2019-2020 competition year. In this role, I work with the rest of the Rules Committee to develop new and challenging rules each year for the competition. One of the great things we have accomplished is adding an emphasis on diversity, equity and inclusion into the competition. We also were able to adapt the competition this past year so that students could continue to compete, even if their schools were not meeting in person due to the pandemic. I’ve served on ASCE’s Seismic Effects and Young Professionals Committee and continue to serve on AISC’s Task Committee 6 on Connections, Task Committee 7 on Evaluation and Repair, Connection Prequalification and Review Panel, and Partners in Education Committee as well as AWS’s task group on tubulars.

Q: We’d love to get an overview of the HSS research you have done previously or are currently working on.

A:My involvement with HSS research goes back to some studies I was involved with in Japan during my post-doc, which used hybrid simulation to study HSS columns in seismic moment frames. At the University of Michigan, my involvement with HSS started with the AISC Milek Fellowship. The focus of the fellowship was to look at seismic applications of HSS, particularly considering how to connect HSS beams to HSS columns in seismic moment frames.

My research group has also explored the use of nontraditional civil engineering materials, such as polymer foams and metal foams as fill materials within HSS members to postpone local buckling and increase energy dissipation capacity under cyclic loads. Through a project funded by NIST, we are also collaborating with other colleagues at Michigan, UC San Diego and National Taiwan University to look at differences in collapse capacity between tube based columns and deep, wide-flange columns used in seismic moment frames. Most of this work involves a combination of large-scale testing and computational modeling. For the computation modeling, we typically use Abaqus or LS-DYNA depending on the project that we’re conducting.

Q: Can you expand on your research on HSS seismic connections a bit more and also your findings? We’re interested to hear ways this research has impacted the industry as a whole.

A: Of course. The focus of the research was to develop a seismic moment connection, which does not currently exist, that could be used to connect HSS beams to HSS columns. Having such a connection available would make it possible to design HSS-based, low-rise, seismic moment frames that can take advantage of the excellent properties of HSS members, thereby potentially reducing the amount of lateral bracing required and the seismic mass of the structure while providing an aesthetically appealing system. We initially considered directly welded connections that were either equal with or had a smaller width beam. Due to the flexibility of the column face and stress concentrations that develop at the corner of the weld, these connections were not able to meet current seismic moment connection requirements for intermediate and special moment frame systems.

To address this problem, we considered a through plate connection and an external diaphragm plate connection, which were both shown to be viable through full-scale connection tests and extensive finite element modeling. The one drawback to these connections was the extensive amount of field welding that would be required. To address the field welding concern and provide a more rapidly installed connection, we conducted further research on a collar-based connection. This connection would only require fillet welds in the field in order to secure the collars, which wrap around an end plate that would be shop-welded to the HSS beams. This connection was also proven to be effective through both experimental testing and extensive finite element modeling. The hope is that this research has helped to inspire those in the industry to think beyond the typical use of HSS and in the future will provide an option for the development of HSS-based seismic moment frame systems.

Q: You coauthored a design guide that was actually a resource for STI’s technical article on HSS bollards. What challenges or obstacles are associated with filling HSS columns with concrete?

A: The biggest challenges or obstacles are the fact that concrete shrinkage within the HSS needs to be accounted for in the design and filling of the members. The shrinkage of the concrete needs to be accounted for to ensure that loads are adequately transferred between the two materials and that they can be carried through the member as expected. There also is limited knowledge in regard to the mechanical bond between concrete and steel, so information in regard to this bond is important, particularly in small HSS members where it may be difficult to have other load transfer mechanisms between the steel and concrete. A final challenge is the fact that there needs to be coordination between the different trades to fill HSS columns with concrete, which does have the potential to lead to delays on a project.

Q: In your extensive experience and research with HSS, are there any insights you would like to offer to designers to consider HSS in signs that may not commonly be known?

A: Aside from what the research I’ve conducted has taught me, a lot of my insight into HSS design comes largely from the fact that I’ve been graced with the ability to work with some great people in academia and industry who are really giants in the field of HSS design. One piece of advice that has always stuck with me is that HSS connections should not be treated as an afterthought. They should be considered in the initial design stages as the size of the HSS member often governs the strength of the connection. Another point to keep in mind is that the face of an HSS member is flexible, and as such, HSS connections often require consideration of limit states that are not typical of connections with other types of members. Finally, bolted connections require special consideration given that access to the inside of the HSS member may not be available to properly tension a bolt. However, even with these considerations, designers should not fear using HSS provided they follow the flow of load through the connection.

Q: From your perspective, what are some challenges young engineers face when entering the field? How can we begin to address them?

A: I think the biggest challenge young engineers face is confidence in their ability and understanding the connection between the theoretical knowledge they’ve gained in the classroom and the practical, system-level requirements of the structural engineering field. From an education standpoint, one way to address both of these challenges is through further emphasis on experiential learning and post-reflection on the process of learning and what has been learned during these experiential opportunities. This combination of immersion and reflection increases a young engineer’s comfort and confidence level in making decisions as they transition from student to professional and allows them to be able to communicate more effectively with their peers. Within the industry, this challenge can be addressed through proper mentorship and encouragement to think creatively when developing different solutions.

Q: What industry innovation would you like to see in the next few years? What are your expectations and how receptive is the industry to new technology, emerging research and software tools?

A: There are two areas that I would like to see innovations occur in the industry over the coming years. One area is in automation and the ability to more rapidly design and construct dependable infrastructure. I see robotics potentially playing a larger role in the structural and construction fields in the future. A second area is the more pervasive use of visualization tools, such as augmented reality and virtual reality, in conjunction with computational tools to improve the design process. The question of adoption of new technology is not necessarily a matter of receptiveness of the industry but more a need to demonstrate a clear benefit to making a change and utilizing emerging research and software tools. This can really only be accomplished with more regular collaboration between those involved in cutting-edge research and those working in industry.