Parametric Analysis in the Optimization Design of Composite Cellular Beams † Maria Célia Loss Brandão, Lorena Yepes-Bellver, Moacir Kripka, Élcio Cassimiro Alves Infrastructures, 2026 This study aims to present a parametric analysis in the optimization problem for steel-concrete composite cellular beams with steel deck slabs. A comparative analysis was carried out considering two scenarios, namely, (i) in the first scenario, the slab span and applied loads were varied, adopting slab configurations from a manufacturer’s catalog for spans of 10 m to 20 m with a step of 2.5 m; (ii) in the second scenario, the same span and loading conditions were considered; however, slab optimization was performed by introducing reinforcement in order to evaluate the resulting impacts on the structural design. In both analyzed scenarios, the objective function was defined as the composite system’s CO2 emissions. The design constraints were defined based on literature recommendations, and to solve the optimization problem, the Particle Swarm Optimization (PSO) algorithm was also adopted. The results demonstrate that the PSO algorithm was effective in identifying optimal solutions and that the introduction of slab reinforcement, combined with optimal design, led to CO2 emission reductions of up to 25% at the highest load levels analyzed.
Manufacturing cost optimization of welded steel plate I-girders integrating hybrid construction and tapered geometry Iván Negrin, Moacir Kripka, Víctor Yepes International Journal of Advanced Manufacturing Technology, 2025 Steel plate I-girders are widely used in the construction industry worldwide. While numerous studies have explored ways to enhance their benefits, few have simultaneously optimized both key mechanical components—geometry and material—to develop novel and more efficient typologies. This research employs metaheuristic optimization to explore alternatives to traditional I-girders, formulating optimization problems that integrate geometric and material variables in both transverse and longitudinal planes. The objective is to minimize manufacturing costs, accounting for material expenses and seven key production activities such as welding, cutting, or painting, while ensuring compliance with Eurocode 3 specifications. The results indicate that material selection dominates in short-span girders, whereas geometric optimization becomes more critical for longer spans. The most cost-effective solution identified is the transversely hybrid with variable section (THVS) girder, which features tapered geometry and hybrid material distribution between the flanges and the web. Based on these findings, practical design recommendations are provided, including optimal span-to-depth ratios, hybrid ratios, taper angles, and transition positions for variable cross-section configurations. A proposed design methodology incorporating these recommendations is validated through a case study, demonstrating that THVS elements can reduce costs by up to 70% compared to traditional designs. However, challenges related to material availability, fabrication complexity, and local buckling risks must be addressed to fully realize the potential of these designs. Future research should prioritize FEA and experimental testing to refine these typologies and update design codes to better account for tapered and hybrid girders.
An integrated framework for optimization-based robust design to progressive collapse of RC skeleton buildings incorporating soil-structure interaction effects Iván Negrin, Ernesto Chagoyén, Moacir Kripka, Víctor Yepes Innovative Infrastructure Solutions, 2025 Structural optimization is crucial in advancing simulation-based engineering by potentially improving design sustainability and resilience. However, optimizing for specific criteria often results in inefficient or vulnerable designs when evaluated against other critical factors. Among these factors, structural safety—particularly buildings’ resistance to progressive collapse (PC)—has garnered increasing attention. Despite significant experimental and numerical studies, the integration of PC resistance into structural optimization remains underexplored. This paper introduces a computational framework, termed Optimization-based Robust Design to Progressive Collapse (ObRDPC), combining simulation-based optimization techniques with PC-resistant design principles. The methodology also incorporates an automated strategy for considering soil-structure interaction (SSI), an aspect usually ignored in optimization-based structural design. The proposed framework is validated through five case studies involving 3D reinforced concrete skeleton buildings, each subjected to two load-bearing element removal scenarios using the Alternate Path method. Results demonstrate the pivotal role of SSI in achieving efficient designs and accurately assessing PC robustness. Neglecting SSI can lead to material usage differences of up to 24.29% and 22.09% in superstructure design following corner and exterior column failures, respectively. Findings also indicate that increasing the number of stories enhances structural robustness. In contrast, buildings with 8-meter spans may incur over 50% higher environmental impact to withstand the failure of a load-bearing element. The study also provides insights into load redistribution mechanisms that beams, columns, and foundations adopt to improve structural resilience. Finally, practical design guidelines are provided to support the replicability and real-world application of the framework, promoting sustainable and resilient infrastructure.
Comparative Life Cycle Assessment of Warehouse Construction Systems Under Distinct End-of-Life Scenarios Paulo Cezar Vitorio Junior, Víctor Yepes, Fabio Onetta, Moacir Kripka Buildings, 2025 There is an increasing demand to replace traditional construction techniques with more sustainable systems that can reduce environmental impacts. Emissions are typically assessed only in carbon dioxide and embodied energy terms, yet these metrics alone cannot fully capture the overall impact generated. This study provides a comparative Life Cycle Assessment (LCA) of three steel warehouse projects with varying cladding systems: steel walls (SW), steel-clay brick walls (SClaW), and steel-concrete block walls (SConW). Life Cycle Assessment (LCA) methodology was used to assess the environmental impact of materials used during the whole life cycle. The study used the software program SimaPro (System for Integrated Environmental Assessment of Products) version 9.6.0.1, with data extracted from the international Ecoinvent database. ReCiPe Midpoint approach were adopted to assess potential impacts. The results indicate that the SW project under end-of-life Scenario 2—waste recycling—exhibited the lowest impacts across most categories, followed by the SConW and SClaW projects. The findings emphasize the environmental benefits of utilizing steel cladding systems over brick or concrete masonry and considering recycling as the end of life of the materials. Additionally, the study provides insights into the significance of material choices in minimizing environmental impact on human health, resource availability, and ecosystems.
Optimum support positions in bridges Universidade de Passo Fundo, Passo Fundo, RS, Brasil, Moacir Kripka, Luttgardes de Oliveira Neto, Universidade Estadual Paulista “Julio de Mesquita Filho”, Câmpus de Bauru, SP, Brasil, Rosana Maria Luvezute Kripka, et al. Ciencia Y Engenharia Science and Engineering Journal, 2013
Cross section optimization using simulated annealing of cold-formed steel channel columns Structural Stability Research Council Annual Stability Conference 2012, 2012
Parameters for the optimal section design of steel cold-formed channel in bending Structural Stability Research Council Annual Stability Conference 2011 ASC, 2011
Workload distribution in institutions of higher education: A formularization for the maximization of the human resources utilization Ciencia Y Engenharia Science and Engineering Journal, 2005
Optimum support positions in building grillages International Conference on Computer Aided Optimum Design of Structures OPTI Proceedings, 2001
Optimization of continuous beams submitted to different boundary conditions Ciencia and Engenharia Science and Engineering Journal, 1999
RECENT SCHOLAR PUBLICATIONS
Integrated optimization framework for fire-resilient and sustainable hybrid steel-concrete composite footbridges FLT Junior, GF de Medeiros, M Kripka, V Yepes Engineering Structures 360, 122779 , 2026 2026
Parametric analysis in the optimization design of composite cellular beams MCL Brandão, L Yepes-Bellver, M Kripka, ÉC Alves Infrastructures 11 (4), 135 , 2026 2026 Citations: 1
Nelder-Mead Optimization Method M Kripka, GF de Medeiros, RML Kripka Encyclopedia of Engineering Optimization and Heuristics, 1-7 , 2026 2026
Optimized and Sustainable Structural Design M Kripka Book accepted for publication by Springer (in pre-release). Forthcoming … , 2026 2026
Artificial Neural Networks Model for Natural Frequency Prediction in Reinforced Concrete Slabs M Kripka, B Marangoni, L Bragagnolo, ZMC Pravia Artificial Intelligence in Civil Engineering: Recent Advances, 39-62 , 2026 2026
Life-cycle environmental impact optimization of an RC-THVS composite frame for sustainable construction I Negrin, M Kripka, V Yepes Engineering Structures 345, 121461 , 2025 2025 Citations: 2
Surrogate-Based Optimization of Steel Girders for Cost and Dynamic Performance M Kripka, FLT Junior, V Yepes, GF de Medeiros XLVI Ibero-Latin American Congress on Computational Methods in Engineering 5 , 2025 2025
Structural Elements M Kripka Optimized and Sustainable Structural Design, 25-54 , 2025 2025
Sustainability-Oriented Structural Optimization M Kripka Optimized and Sustainable Structural Design, 107-123 , 2025 2025
Final Reflections and Perspectives M Kripka Optimized and Sustainable Structural Design, 125-126 , 2025 2025
Truss Structures M Kripka Optimized and Sustainable Structural Design, 55-78 , 2025 2025 Citations: 1
Grillages and Frames M Kripka Optimized and Sustainable Structural Design, 79-105 , 2025 2025
Where Optimization Begins M Kripka Optimized and Sustainable Structural Design, 5-23 , 2025 2025
Do Berço ao Portão: Avaliação Comparativa das Emissões de Estruturas em Concreto Armado Produzidas no Sul do Brasil M Kripka, JJ Alievi, JF Santoro, PCV Junior CONCRETO & Construções-ISSN 1809-7197 119 (Edição 119) , 2025 2025
An integrated framework for Optimization-based Robust Design to Progressive Collapse of RC skeleton buildings incorporating Soil-Structure Interaction effects I Negrin, E Chagoyén, M Kripka, V Yepes Innovative Infrastructure Solutions 10 (9), 446 , 2025 2025 Citations: 1
Manufacturing cost optimization of welded steel plate I-girders integrating hybrid construction and tapered geometry I Negrin, M Kripka, V Yepes The International Journal of Advanced Manufacturing Technology 140 (3), 1601 … , 2025 2025 Citations: 3
Experimental study of human-induced vibrations on glued laminated timber floors JM Bresolin, M Kripka, ZMC Pravia Structures 79, 109375 , 2025 2025 Citations: 1
Practical Application of LCA to Optimize Environmental Impacts of Steel–concrete Footbridges FL Tres Junior, V Yepes, GF de Medeiros, M Kripka The Contribution of Life Cycle Analyses and Circular Economy to the … , 2025 2025 Citations: 1
Design optimization of a composite typology based on RC columns and THVS girders to reduce economic cost, emissions, and embodied energy of frame building construction I Negrin, M Kripka, V Yepes Energy and Buildings 336, 115607 , 2025 2025 Citations: 5
Comparative life cycle assessment of warehouse construction systems under distinct end-of-life scenarios PC Vitorio Junior, V Yepes, F Onetta, M Kripka Buildings 15 (9), 1445 , 2025 2025 Citations: 3
MOST CITED SCHOLAR PUBLICATIONS
Optimization of reinforced concrete columns according to different environmental impact assessment parameters GF de Medeiros, M Kripka Engineering Structures 59, 185-194 , 2014 2014 Citations: 134
Discrete optimization of trusses by simulated annealing M Kripka Journal of the brazilian society of mechanical sciences and engineering 26 … , 2004 2004 Citations: 91
Metamodel-assisted design optimization in the field of structural engineering: A literature review I Negrin, M Kripka, V Yepes Structures 52, 609-631 , 2023 2023 Citations: 63
Optimization of reinforced concrete building frames with automated grouping of columns JT Boscardin, V Yepes, M Kripka Automation in Construction 104, 331-340 , 2019 2019 Citations: 57
Usage of optimization techniques in civil engineering during the last two decades T Dede, M Kripka, V Togan, V Yepes, RV Rao Current Trends in Civil & Structural Engineering 2 (1), 1-17 , 2019 2019 Citations: 57
Big crunch optimization method M Kripka, RML Kripka International conference on engineering optimization, Brazil, 1-5 , 2008 2008 Citations: 52
Minimizing environmental impact from optimized sizing of reinforced concrete elements JF Santoro, M Kripka Computers and Concrete 25 (2), 111-118 , 2020 2020 Citations: 50
Use of optimization for automatic grouping of beam cross-section dimensions in reinforced concrete building structures M Kripka, GF Medeiros, ACC Lemonge Engineering structures 99, 311-318 , 2015 2015 Citations: 49
Selection of sustainable short-span bridge design in Brazil M Kripka, V Yepes, CJ Milani Sustainability 11 (5), 1307 , 2019 2019 Citations: 44
Artificial intelligence applications in civil engineering T Dede, AR Vosoughi, M Grzywinski, M Kripka Hindawi , 2019 2019 Citations: 41
Optimization of steel-concrete composite beams considering cost and environmental impact AF Tormen, ZMC Pravia, FB Ramires, M Kripka Steel and Composite Structures, 409-421 , 2022 2022 Citations: 39
Metamodel-assisted meta-heuristic design optimization of reinforced concrete frame structures considering soil-structure interaction I Negrin, M Kripka, V Yepes Engineering Structures 293, 116657 , 2023 2023 Citations: 38
Study of alternatives for the design of sustainable low-income housing in Brazil PF Bianchi, V Yepes, PC Vitorio Jr, M Kripka Sustainability 13 (9), 4757 , 2021 2021 Citations: 38
Optimum design of reinforced concrete columns subjected to uniaxial flexural compression R Bordignon, M Kripka Computers and Concrete, 327-340 , 2014 2014 Citations: 38
Multi-criteria optimization for sustainability-based design of reinforced concrete frame buildings I Negrin, M Kripka, V Yepes Journal of Cleaner Production 425, 139115 , 2023 2023 Citations: 37
Determinação das emissões de dióxido de carbono das matérias primas do concreto produzido na região norte do Rio Grande do Sul JF Santoro, M Kripka Ambiente Construído 16, 35-49 , 2016 2016 Citations: 37
Structural optimization and proposition of pre-sizing parameters for beams in reinforced concrete buildings GF de Medeiros, M Kripka Computers and Concrete, 253-270 , 2014 2014 Citations: 32
Life cycle assessment of bridges using Bayesian networks and fuzzy mathematics ZW Zhou, J Alcalá, M Kripka, V Yepes Applied Sciences 11 (11), 4916 , 2021 2021 Citations: 30
Design optimization of welded steel plate girders configured as a hybrid structure I Negrin, M Kripka, V Yepes Journal of Constructional Steel Research 211, 108131 , 2023 2023 Citations: 28
Proposal of sustainability indicators for the design of small-span bridges CJ Milani, V Yepes, M Kripka International Journal of Environmental Research and Public Health 17 (12), 4488 , 2020 2020 Citations: 27