(1) testing and simulation, such as hybrid simulation, for characterization of innovative and sustainable materials and structures,
(2) autonomous damage assessment, by developing digital twins with structural health monitoring and artificial intelligence capabilities, and
(3) developing infrastructure asset investment planning tools for management of existing and new assets that enable infrastructure authorities and municipalities to use monitoring data-driven insights to guide decision making and capital investment planning over the life of an asset.
An illustration for cyber-physical testing and simulation is Amirali’s dissertation research on Multi-Axial Real-Time Hybrid Simulation, which allows for characterization of structural systems subject to natural hazards, by only testing structural elements of interest and numerically simulating the rest of the structure. This method ensures that real-world complexities, such as dynamic and nonlinear behaviors, are incorporated into laboratory testing, while allowing for rapid deployment, testing flexibility, cost and space savings.
Scholarly Writing
A. Najafi, G.A. Fermandois, S.J. Dyke, and B.F. Spencer, “Hybrid simulation with multiple actuators: A state-of-the-art review”, Engineering Structures, vol. 276, 2023. 10.1016/j.engstruct.2022.115284
S. Wang, C. Rodgers, G. Zhai, T. N. Matiki, B. Welsh, A. Najafi, J. Wang, Y. Narazaki, V. Hoskere, and B.F. Spencer, “A graphics-based digital twin framework for computer vision-based post-earthquake structural inspection and evaluation using unmanned aerial vehicles”, Journal of Infrastructure Intelligence and Resilience, vol. 1, 2022. 10.1016/j.iintel.2022.100003
O. Lawal, A. Najafi, T. Hoang, S.A.V. Shajihan, K. Mechitov, and B.F. Spencer, “Development and Validation of a Framework for Smart Wireless Strain and Acceleration Sensing”, Sensors, vol. 5, 2022. Available: 10.3390/s22051998
S. Tell, A. Andersson, A. Najafi, B.F. Spencer, and R. Karoumi, “Improved dynamic resilience of railway bridges using external dampers”, Rail Infrastructure Resilience, A Best-Practices Handbook, vol. 10, 2022. Available: 10.1016/B978-0-12-821042-0.00013-7
A. Najafi, “Multi-axial real-time hybrid simulation framework for testing nonlinear structure systems with multiple boundary interfaces”, Doctoral Dissertation, University of Illinois at Urbana-Champaign, 2021. https://www.ideals.illinois.edu/handle/2142/110408
A. Najafi, B.F. Spencer, “Multiaxial Real-time Hybrid Simulation for Substructuring with Multiple Boundary Points”, Journal of Structural Engineering, vol. 147(11), 2021. Available: 10.1061/(ASCE)ST.1943-541X.0003138
S. Tell, A. Andersson, A. Najafi, B.F. Spencer, and R. Karoumi, “Real-time hybrid testing for efficiency assessment of magnetorheological dampers to mitigate train-induced vibrations in bridges”, International Journal of Rail Transportation, 2021. Available: 10.1080/23248378.2021.1954560
A. Najafi and B.F. Spencer, “Adaptive model reference control method for real-time hybrid simulation”, Mechanical Systems and Signal Processing, vol. 132, pp. 183-193, 2019. Available: 10.1016/j.ymssp.2019.06.023
A. Najafi and B.F. Spencer, “Validation of model-based real-time hybrid simulation for a lightly-damped and highly-nonlinear structural system”, Journal of Applied and Computational Mechanics, vol. 7, 2020. Available: 10.22055/JACM.2020.32584.2039
A. Najafi, G.A. Fermandois, B.F. Spencer, “Decoupled model-based real-time hybrid simulation with multi-axial load and boundary condition boxes”, Engineering Structures, vol. 219, 2020. Available: 10.1016/j.engstruct.2020.110868
A. Najafi, B.F. Spencer, “Modified model-based control of shake tables for online acceleration tracking”, Earthquake Engineering and Structural Dynamics, 2020. Available: 10.1002/eqe.3326
Teaching
Online content:
Amirali has developed three online courses on intermediate and advance level structural engineering topics. These online courses are comprised of 10 videos each and convey the most important aspects of each topic.
Teaching history:
Course instructor: CEE360 - Introduction to Structural Engineering (Spring 2018)