Gazi University Journal of Science 2147-1762 Gazi University 10.35378/gujs.1843545 Civil Geotechnical Engineering Numerical Modelization in Civil Engineering Soil Mechanics in Civil Engineering İnşaat Geoteknik Mühendisliği İnşaat Mühendisliğinde Sayısal Modelleme İnşaat Mühendisliğinde Zemin Mekaniği Influence of Aspect Ratio on the Performance of Geocell-Reinforced Footings in Sandy Soils Kumlu Zeminler Üzerine Yerleştirilmiş Geocell ile Güçlendirilmiş Temellerin Performansına En Boy Oranının Etkisi https://orcid.org/0000-0002-0459-7129 Gürbüz Ayhan GAZI UNIVERSITY https://orcid.org/0000-0003-1264-237X Yünkül Kaan TOKAT GAZİOSMANPAŞA ÜNİVERSİTESİ https://orcid.org/0000-0001-8576-0807 Demirdogen Sarper Kansas University https://orcid.org/0000-0003-2561-3738 Kalkan Hüseyin GAZI UNIVERSITY Advanced Online Publication 12 16 2025 03 26 2026 Copyright © 1988, Gazi University Journal of Science 1988 Gazi University Journal of Science

The aspect ratio of the shallow footing is a key parameter affecting the bearing capacity performances. However, the recommendations of previous studies exhibit notable inconsistencies among themselves for the unreinforced condition, and no numerical study in the literature has investigated the effect of aspect ratio under geocell-reinforced condition. This pioneer study investigates the influence of footing aspect ratio and soil relative density on the ultimate bearing capacity, shape factor, improvement factor, and failure mechanism of unreinforced and geocell-reinforced footings resting on sandy soils. A total of 36 rigorous three-dimensional finite element analyses were performed and validated against physical model tests. The analyses considered footings with aspect ratios ranging from 1 to 10 placed on loose and dense sands. The results showed that geocell reinforcement substantially improves footing performance by increasing bearing pressures, ultimate bearing capacities, stiffness of the footing pressure versus footing settlement ratio curves and shape factor values. Improvement factors were observed to lie between 1.12 and 2.56, with square footings showing the maximum improvement, and the magnitude of improvement increasing as the relative density increased. Furthermore, for unreinforced footings, the maximum shape factor occurred at aspect ratio of 2, whereas in geocell-reinforced conditions, the peak shifted to aspect ratio of 1. The shape factor values also increased with increasing relative density. Moreover, it was observed that the aspect ratio influences both the failure surface geometry and reinforcement mechanism of geocell.

Bu çalışmada, temelin en-boy oranının ve zemin rölatif sıkılığının, kum zeminler üzerine yerleştirilen hem güçlendirilmemiş hem de geocell ile güçlendirilmiş temellerin nihai taşıma gücü, şekil faktörü, iyileştirme faktörü ve yenilme mekanizması üzerindeki etkisini araştırmaktadır. Bu kapsamda, fiziksel model deneyleriyle doğrulanan toplam 36 adet kapsamlı üç boyutlu sonlu elemanlar analizi gerçekleştirilmiştir. Analizler, en-boy oranı 1 ile 10 arasında değişen temeller ile gevşek ve sıkı kum koşulları için değerlendirilmiştir. Elde edilen sonuçlar, geocell donatısının temel gerilmelerini, nihai taşıma kapasitelerini, gerilme-deplasman oranı eğrilerinin rijitliğini ve şekil faktörü değerlerini artırarak temel performansını önemli ölçüde iyileştirdiğini göstermiştir. İyileşme faktörlerinin 1.12 ile 2.56 arasında değiştiği, en yüksek iyileşmenin kare temellerde elde edildiği ve rölatif sıkılığın artışı ile birlikte iyileşme faktörü değerlerinin artış gösterdiği gözlemlenmiştir. Ayrıca, güçlendirilmemiş temellerde maksimum şekil faktörünün en-boy oranının 2’ye eşit olduğu durumda görülürken, geocell ile güçlendirilme sonucunda bu pik değer en-boy oranı 1’e kaymıştır. Yapılan çalışmadan elde edilen bulgular, sığ temelin en-boy oranının ve zeminin rölatif sıkılığın geocell ile güçlendirilmiş temellerin performansı üzerindeki önemli etkisini vurgulayarak, pratik uygulamalarda temel geometrisi ve donatı tasarımının optimize edilmesi için değerli rehberlik sağlamaktadır.

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