PSI - Issue 84

Ahmed Amir Khalil et al. / Procedia Structural Integrity 84 (2026) 1031–1038

1038

5. Conclusions This study demonstrates the effectiveness of the Applied Element Method (AEM) in supporting the safe planning and execution of decommissioning operations for complex industrial infrastructures, such as hung boiler units and reinforced concrete stacks. High-fidelity 3D modeling and nonlinear dynamic simulations provided several key benefits: • Accurate representation of structural behavior under extreme loads and large deformations, including progressive collapse mechanisms and element separation, Pellecchia et al. (2024). • In the boiler unit, stresses analysis revealed critical load redistribution during the cutting stages, with columns reaching approximately 190 MPa, close to the yield strength. This insight enabled the correct design of strengthening measures to maintain safety margins. • Optimization of demolition strategies, including the design of scarfing operations and strengthening details (e.g., welding steel plates to flanges) to ensure safe installation of shaped charges. • Quantification of debris spread and collapse height, facilitating planning for debris removal and site clearance operations. • Validation of collapse sequences through comparison between simulation results and real-world observations, confirming the reliability of AEM for practical applications, Domaneschi et al. (2020). • Evaluation of alternative demolition scenarios, showing measurable improvements in the refined plan for the reinforced concrete stack: deviation reduced from 30° to 7° and vertical drop significantly minimized. • Design of additional mitigation measures, such as steel props to reinforce construction opening, reducing the risk of premature failure during blasting. Integrating AEM into decommissioning procedures enhances safety, mitigates operational risks, and improves overall efficiency. References Slavin Matthew, Ph.D., Brown Tatiana, 2011, The American Clean Skies Foundation report "Repurposing Legacy Power Plants: Lessons for the Future" American Clean Skies Foundation (ACSF). Applied Science International, 2004, Technical Manual of Extreme Loading for Structures, Durham, North Carolina. Tagel-Din, H., 2009, High Fidelity Modelling of Building Collapse with Realistic Visualization of Resulting Damage and Debris Using the Applied Element Method, Report submitted to Défense threat Reduction Agency by Applied Science International, LLC, ASI- Approved for Public Release. Grunwald, C., A. A. Khalil, B. Schaufelberger, E. M. Ricciardi, C. Pellecchia, E. De Iuliis, and W. Riedel. 2018, “Reliability of collapse simulation– Comparing finite and applied element method at different levels.” Eng. Struct. 176 (Dec): 265–278. https://doi.org/10.1016/j.engstruct.2018.08.068. Meguro K, Tagel-Din H., 2000, Applied element method for structural analysis: theory and applications for linear materials. Structural Engineering Earthquake Engineering JSCE, 17(2):215 – 24. Meguro K, Tagel-Din H., 2001, Applied Element Simulation of RC Structures under Cyclic Loading. Journal of Structural Engineering ASCE, 127(11):1295 – 305. Meguro K, Tagel-Din H., 2002, AEM Used for Large Displacement Structure Analysis. Journal of Natural Disaster Science; 24(1):25 – 34. Tagel-Din H, Rahman N., 2004, Extreme loading: breaks through finite element barriers. Structural Engineer 2004, 5(6):32 – 340. Pellechia Cosimo, Cardoni Alessandro, Ph.D., Cimellaro Gian Paolo, Ph.D., Domaneschi Marco, Ph.D., Ansari Farhad, Ph.D., and Khalil Ahmed Amir, Ph.D., 2024, Progressive Collapse Analysis of the Champlain Towers South in Surfside, Florida, J. Struct. Eng ASCE., 2024, 150(1): 04023211 Domaneschi, M., C. Pellecchia, E. De Iuliis, G. P. Cimellaro, M. Morgese, A. A. Khalil, and F. Ansari. 2020. “Collapse analysis of the Polcevera viaduct by the applied element method.” Eng. Struct. 214 (Jul): 110659. https://doi.org/10.1016/j.engstruct.2020.110659.