2023 Journal Papers from the Group

2023 was a busy year for the TW Group as usual! Below is a list of 2023 journal articles, links to the article, and a few thoughts on why you might want to read our latest work.

Codes and Standards

Schafer, B.W., Glauz, R.S., Chen, H. (2023). “Revision of ASCE 8 – Design of cold-formed stainless steel structural members.” Journal of Constructional Steel Research, 208, art. no. 107986, DOI: 10.1016/j.jcsr.2023.107986
{After 20 years! we finally got the experts back together and updated the cold-formed stainless steel standard. It was a huge undertaking with an army of volunteers, learn about all the work and get a preview of the new ASCE 8-22. I was proud to Chair the effort, and look forwarding to starting a new cycle in 2024.}

Cold-Formed Steel Members and Optimization

Akchurin, D., Ding, C., Xia, Y., Blum, H.B., Schafer, B.W., Li, Z. (2023). “Instability-driven family optimization of cold-formed steel lipped-channel cross-sections with strength and stiffness constraints.” Thin-Walled Structures, 192, art. no. 111118, DOI: 10.1016/j.tws.2023.111118
{Back a few years ago Zhanjie Li and I wrote a paper that showed that you could replace the 100’+ SFIA CFS shapes with just a small few and structural still do better. We went one further here and showed that this holds up even for stiffness – and we provided the small family of optimal shapes. Who knows maybe change will come for the industry in 2024 and some of these ideas will be further embraced. Meanwhile we will keep pushing towards greater efficiency for CFS.}

Farzanian, S., Louhghalam, A., Schafer, B.W., Tootkaboni, M. (2023). “Geometric imperfections in CFS structural members: Part I: A review of the basics and some modeling strategies.” Thin-Walled Structures, 186, art. no. 110619, DOI: 10.1016/j.tws.2023.110619
Farzanian, S., Louhghalam, A., Schafer, B.W., Tootkaboni, M. (2023). “Geometric imperfections in CFS structural members, Part II: Data-driven modeling and probabilistic validation.” Thin-Walled Structures, 185, art. no. 110620, DOI: 10.1016/j.tws.2023.110620
{We have long examined the role of geometric imperfections in CFS strength. Teaming up with Mazdak Tootkaboni provides some higher end reliability tools to look at this further. Here we provide our latest ideas on probabilistic modeling and uncertainty for cold-formed steel member strength.}

Abbasi, M., Rasmussen, K.J.R., Khezri, M., Schafer, B.W. (2023). “Computational modelling of built-up cold-formed steel columns and parametric studies.” Thin-Walled Structures, 191, art. no. 111035, DOI: 10.1016/j.tws.2023.111035
Abbasi, M., Rasmussen, K.J.R., Khezri, M., Schafer, B.W. (2023). “Experimental investigation of the sectional buckling of built-up cold-formed steel columns.” Journal of Constructional Steel Research, 203, art. no. 107803, DOI: 10.1016/j.jcsr.2023.107803
{Our teams collaborations with Professor Kim Rasmussen at Sydney Uni go back many years. Lately, we have been working on cold-formed steel built-up shapes. Built-up shapes have a strong role to play in taller more robust CFS structures, and this work provides clear insights and guidance for the modern CFS engineer.}

Zhao, X., Wang, G., Sun, X., Wang, X., Schafer, B.W. (2023). “Modeling of uncertain geometry of cold formed steel members based on laser measurements and machine learning.” Engineering Structures, 279, art. no. 115578, DOI: 10.1016/j.engstruct.2022.115578
{Dr. Xi Zhao, who created the laser scanning rig in our lab when she was a student, continues to advance the sweet science of scanning and creating useful data for CFS construction. This latest work provides new methods for using realistic data, and ties into our other work on data-driven modeling. It’s all coming together to improve our ability to model and predict cold-formed steel members.}

He, Z., Peng, S., Zhou, X., Yang, G., Schafer, B.W. (2023). “Failure characteristics of cold-formed steel built-up sections with web stiffeners under axial and eccentric compression.” Thin-Walled Structures, 182, art. no. 110269, DOI: 10.1016/j.tws.2022.110269
{Ziqi He’s visit to our group a few years back was very productive and has led to several papers, including this latest one on built-up shapes under eccentric load.}

Earthquake Engineering

Wei, G., Foroughi, H., Torabian, S., Eatherton, M.R., Schafer, B.W. (2023). “Seismic Design of Diaphragms for Steel Buildings Considering Diaphragm Inelasticity.” Journal of Structural Engineering (United States), 149 (7), art. no. 04023077, DOI: 10.1061/JSENDH.STENG-11832
{This incredible paper combines two PhD theses into one short, digestible paper! Working with the incredible SDII team, we are able to show the role of diaphragm inelasticity in building structural earthquake response. Importantly we show that new diaphragm design methods can be successfully used in the design of these buildings and it is possible to move diaphragm design from an implicit exercise driven by estimates about the vertical system to an explicit exercise where one designs the horizontal force resisting system. We will have more to say on this topic in the future, but for now this provides all of the key insights.}

Fischer, A.W., Schafer, B.W. (2023). “Wall-diaphragm interactions in seismic response of building systems I: Parametric models and elastic response.” Earthquake Engineering and Structural Dynamics, 52 (6), pp. 1678-1703. DOI: 10.1002/eqe.3836
Fischer, A.W., Schafer, B.W. (2023). “Wall-diaphragm interactions in seismic response of building systems ii: Inelastic response and design.” Earthquake Engineering and Structural Dynamics, 52 (5), pp. 1557-1577. DOI: 10.1002/eqe.3829
{Can you use simple models to understand complex phenomena? Yes, yes you can. Here Dr. Fischer shows how by introducing a nonlinear DOF for the diaphragm one can explore holistically the expected performance between the vertical and horizontal lateral force resisting systems. Importantly, the work shows how the vertical (walls) can shield the diaphragm with inelasticity, but the diaphragm has a much harder time shielding the walls. These papers are a roadmap for all that needs to be corrected and incorporated in earthquake design to properly account for interactions between walls and diaphragms.} 

Eladly, M.M., Schafer, B.W. (2023). “Evaluation of Seismic Deflection Amplification Factor for Buildings Utilizing Cold-Formed Steel-Framed Shear Walls.” Journal of Structural Engineering (United States), 149 (7), art. no. 04023075, DOI: 10.1061/JSENDH.STENG-11987
{ELF Seismic design in ASCE 7 uses the factor Cd to amplify for nonlinear seismic displacements. AISI S400 also has a nonlinear expression for static displacements. If you use both, the predicted deflections are much higher than nonlinear models – so what should the engineer do? Read this paper to find out, and the ideas detailed herein were adopted in the next edition of AISI S400…}

Zhang, Z., Eladly, M.M., Rogers, C.A., Schafer, B.W.(2023). “Cold-formed steel framed shear wall test database.” Earthquake Spectra, DOI: 10.1177/87552930231202974
{We have pulled together 100’s of CFS shear wall tests to enable improved design codes, data-driven methods, and as a means to better understand the performance of CFS shear walls. Read all about our database in this paper and then go to DesignSafe and get the database for yourself.}

Wind turbine support towers

{So many conference papers on wind turbine support towers in 2023, but the only journal article from the group was part of Adam Sadowski’s benchmark study on computational shell buckling. (Great work Dr. Fischer!) We have many more articles in the works, but I guess it is always good to have something to look forward to…}  

Some great 2024 papers already available…

Akchurin, D., Sabelli, R., Ziemian, R.D., Schafer, B.W. (2024).”ASD and LRFD: Reliability comparison for designs subjected to wind loads.” Journal of Constructional Steel Research, 213, art. no. 108327, DOI: 10.1016/j.jcsr.2023.108327
Sabelli, R., Ziemian, R.D., Schafer, B.W. (2024). “ASD and LRFD lateral load combinations: Comparison of required strength and reliability for design of structural steel.” Journal of Constructional Steel Research, 212, art. no. 108210, DOI: 10.1016/j.jcsr.2023.108210

Avellaneda-Ramirez, R.E., Eatherton, M.R., Easterling, W.S., Schafer, B.W., Hajjar, J.F. (2024). “Experimental Program on Behavior of Concrete-Filled Steel Deck Composite Diaphragms.” Journal of Structural Engineering (United States), 150 (2), art. no. 04023225, DOI: 10.1061/JSENDH.STENG-12556

Xia, Y., Glauz, R.S., Schafer, B.W., Seek, M., Blum, H.B. (2024). “Cold-formed steel strength predictions for torsion and bending–torsion interaction.” Thin-Walled Structures, 195, art. no. 111367, DOI: 10.1016/j.tws.2023.111367

Ding, C., Xia, Y., Li, Z., Blum, H.B., Schafer, B.W. (2024). “Strength of Bolted Lap Shear Connections with Advanced High-Strength Steel Sheets.” Journal of Structural Engineering (United States), 150 (1), art. no. 04023208, DOI: 10.1061/JSENDH.STENG-12470

Wei, G., Schafer, B.W., Seek, M., Eatherton, M.R. (2024). “Evaluating the use of standing seam roof as beam lateral bracing.” Journal of Constructional Steel Research, 212, art. no. 108244, DOI: 10.1016/j.jcsr.2023.108244