Ultimate Load Capacity of Group-Pile Supported Jacket Foundations for Offshore Wind Energy Converters

Öz

This study was performed to investigate the ultimate horizontal load capacity of an innovative foundation system for large offshore wind energy turbines (i.e. ∼5-7 MW) to be constructed in deep waters, ∼35-40 m. The ultimate capacity of the standart jacket foundation system with single piles and double-pile supported novel jacket foundation system were estimated using hyperbolic method. Numerical method was used to evaulate the response of the foundations under combined loading in saturated very dense sand. The validation of the developed finite element model for two cases was made using the results of field tests in the literature. The effect of pile length and pile spacing on the ultimate capacity were determined by parametric analysis. The results indicate that the jacket foundation with closely spaced piles provides higher ultimate load capacity and shows a significantly better response than the response of a single-pile configuration with embedded length L, although the total length of the piles is same.

Anahtar Kelimeler

• Ultimate bearing capacity,Lateral load,Offshore wind energy converters,Jacket foundation,Numericalt method,Hyperbolic Method

Açık Deniz Rüzgar Enerjisi Türbinleri Grup Kazıklı Jacket Temel Sistemi Yük Taşıma Kapasitesi

Öz

Bu çalışmada derin sularda (∼35-40 m) uygulanabilecek yüksek kapasiteli (∼5-7 MW) rüzgar enerjisi türbinleri için önerilen yenilikçi jacket temel sisteminin davranışı nihai taşıma kapsitesi açısından incelenmiştir. Tek kazıklı standart jacket ile yakın mesafeli çift kazıklı yenilikçi jacket temel sistemlerinin yatay yük taşıma kapasiteleri karşılaştırılmıştır. Yatay yük kapasitesi tahmini için hiperbolik yöntem kullanılmıştır. İnceleme suya doygun çok sıkı kum zemin ortamında ve statik kombine yükleme koşullarında gerçekleştirilmiştir. Araştırma üç boyutlu sayısal analiz yöntemine dayanmaktadır. Sonlu elemanlar modelinin doğrulaması literatürde yer alan arazi deney sonuçları ile gerçekleştirilmiştir. Parametrik analiz yöntemi ile kazık uzunluğu ve kazıklar arası mesafenin yatay yük taşıma kapasitesi üzerindeki etkisi incelenmiştir. Sonuçlar toplamda aynı kazık uzunluğuna sahip temel sistemi durumunda dahi çift kazık kullanımının jacket temel siteminin deplasman birikimini önemli ölçüde azalttığını ve yatay yük taşıma kapasitesini önemli dercede arttırdığını göstermektedir.

Anahtar Kelimeler

• Nihai yük kapasitesi,Yatay yük,Açık deniz rüzgar enerjisi,Jacket temel,Sonlu elemanlar yöntemi,Hiperbolik metot

Kaynakça

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