Ibrahim Behram Ugur

In recent years, metaheuristic optimization methods have been widely applied across various engineering disciplines, offering effective solutions to complex problems that require both efficiency and reliability. Within this context, this study has two primary objectives. The first is to apply the Dandelion Optimizer (DO), inspired by the three-stage flight of dandelion seeds, to the optimum design of spatial steel frames and to evaluate its performance as a structural optimization algorithm. The second is to investigate the influence of different soil types, as defined in the Turkish Building Earthquake Code (TBEC-2018), on the optimum design outcomes. For this purpose, three benchmark spatial steel frames consisting of 132, 428, and 720 members were optimized using DO. The algorithm was implemented in MATLAB R2017b and integrated with SAP2000 v19 via the Open Application Programming Interface (OAPI). The design process was performed in accordance with TBEC-2018 and the AISC-LRFD, with strength, stability, and serviceability constraints considered. The results indicate that deteriorating soil conditions from ZA to ZE lead to substantial increases in structural demands. In the three analyzed models, total weight increases within the range of 45–57%, whereas total seismic base shear shows a much sharper rise, ranging from 160% to 292% These findings demonstrate both the practical applicability of the DO in steel frame optimization and the critical impact of soil conditions on structural design, underlining the importance of incorporating geotechnical factors into optimization frameworks.

Rüzgâr yükleri, çelik yapıların taşıyıcı sistem davranışını doğrudan etkileyen en önemli dış yüklerden biridir. Bu çalışmada, üç farklı endüstriyel çelik yapı modeli (çift eğimli düzlem kafes sistem, dolu gövdeli kiriş sistemi ve düzlem yüzeyli uzay kafes sistem) üzerinde TS 498, Eurocode 1-4 ve ASCE 7-10 standartlarına göre hesaplanan rüzgâr yükleri uygulanarak karşılaştırmalı analizler yapılmıştır. Statik analizler SAP2000 yazılımı ile gerçekleştirilmiş, tasarımlar Çelik Yapıların Tasarım, Hesap ve Yapım Esasları (ÇYTHYE 2018) esas alınarak yapılmış, deprem etkileri ise Türk Bina Deprem Yönetmeliği (TBDY 2018) kapsamında modele dâhil edilmiştir. Analiz sonuçları, yapı ağırlıkları açısından TS498 standardı ile Eurocode1-4’e göre yaklaşık %10, ASCE 7-10 ile ise yaklaşık %14 daha hafif tasarımlar elde edildiğini göstermiştir. Buna göre, Eurocode 1-4’ün ayrıntılı yaklaşımı nedeniyle en yüksek yapı ağırlıklarını ve taban kesme kuvvetlerini verdiğini; ASCE 7-10’un yüksekliği nispeten daha az olan yapılar için maruziyet katsayısının düşük kalması sonucu daha düşük rüzgâr yükleri ve dolayısıyla en hafif çözümleri ürettiğini; TS 498’in ise pratik ancak detay açısından sınırlı hesap yöntemiyle iki standart arasında sonuçlar sunduğunu göstermektedir. Elde edilen bulgular, yönetmelik seçimlerinin endüstriyel çelik yapıların kesit boyutları, ağırlıkları ve güvenlik düzeyi üzerinde belirleyici rol oynadığını ortaya koymaktadır.

This paper introduces a novel hybrid metaheuristic optimization algorithm, combining improved formulations of the Slime Mould Algorithm (SMA) and the Jaya Algorithm (JA) (HSMJA) with online distributed computing (ODC), referred to as HSMJA-ODC. While HSMJA hybridizes the improved versions of SMA and JA formulations to maximize searchability, ODC significantly reduces the computation time of the optimization process. The proposed HSMJA-ODC algorithm is used for the weight minimization of steel space frames under strength, displacement, and geometric size constraints. The optimization results obtained from three steel frames confirm the efficiency and robustness of the proposed HSMJA-ODC algorithm, which consistently converges on competitively optimized designs in comparison to its rivals. Moreover, distributed computing reduces computation time by more than 80% compared to single-computer implementations.

Incorporating frequency constraints into the optimum design of large-scale truss dome structures is crucial for maintaining seismic resilience, as the natural frequencies must remain within specified ranges. In this work, seven metaheuristic algorithms—including three variants of the Fitness–Distance–Balance-based Adaptive Guided Differential Evolution (FDB-AGDE), the Cheetah Optimizer (CO), the Bonobo Optimizer (BO), the Flood Algorithm (FLA), and the Lung Performance Optimization (LPO) are applied to solve high-dimensional truss sizing problems under strict frequency limitations. Their convergence characteristics and solution quality are systematically compared across multiple dome configurations. Besides traditional measures of computational efficiency and final weight minimization, a suite of statistical analyses is conducted: the Wilcoxon rank-sum test to assess pairwise performance significance, the Friedman test to establish overall rank ordering, and Cohen’s test to quantify effect sizes. The results reveal that LPO, BO, CO, and the first variant of FDB-AGDE consistently produce lighter feasible designs with lower variability, whereas FLA and other variants of FDB-AGDE exhibit heavier structures or higher dispersion. The findings underscore the value of robust, well-tuned metaheuristics and rigorous statistical evaluation in structural optimization, offering clear guidance for seismic-focused designers seeking both lightweight solutions and reliable performance across repeated runs.

This paper presents a new approach to the circulatory system-based optimization algorithm called NCSBO. The proposed method incorporates an adaptive parameter-tuning strategy and a refined mutation approach to improve the performance of optimizing the shape and size of truss structures. The adaptive parameter tuning dynamically adjusts the number of weaker solutions according to the diversity of the population, enabling the algorithm to intelligently balance exploration and exploitation. The mutation strategy selectively alters only one variable of the best solution, preserving its overall structure while conducting a detailed local search to exploit promising regions more efficiently. The validation of the proposed algorithm involves four different truss examples. The design constraints include stress, displacement, and buckling, and are considered in the optimum design. A comprehensive assessment of the NCSBO on various benchmark design examples is carried out and compared with state-of-the-art methods published in the literature. The results demonstrate the NCSBO algorithm’s superiority in achieving the optimum design, and statistical findings support its consistent ability to obtain competitive solutions.