ANALYSIS OF RAFT FOUNDATION ON SANDY SOILS BY WINKLER AND PSEUDO-COUPLED METHODS

Year 2023, Volume: 31 Issue: 2, 675 - 688, 21.08.2023

İlyas Özkan , Yavuz Yenginar , Ali Serdar Ecemiş

https://doi.org/10.31796/ogummf.1224081

Abstract

The settlements occurred in building foundations depend on many soil parameters. Thus, these parameters make the solution both difficult and complex during the calculating process. Therefore, finite element programs use the subgrade reaction coefficient to facilitate the foundation solution. Two different methods, which are Winkler method and Pseudo coupled method, are used in the basic solutions with the coefficient of subgrade reaction. While the Winkler method can be solved with a single field, the pseudo method can be solved with 2 or more fields. In this study, a 10 story building with a 36 m x 36 m square foundation was separately designed on four different sand soils. Two of these soils are classified as C and the others are classified as D according to Eurocode 8. The foundation of this building built on four different soils was divided into six different areas (one region, two regions, three regions, five regions, seven regions, 10 regions). Consequently, 24 analyzes were performed by using the ETABS program. According to the results obtained from these analyzes, while it is appropriate to use the Winkler method in weak sand soils for rigid foundation acceptance, it is more appropriate to use the Pseudo-coupled method in dense sand soils. Pseudo-coupled method should be used in flexible foundation solutions built on weak sand soils. The Winkler method should be used for flexible foundations built on dense sand soils. In the Pseudo-coupled method, the highest settlements were obtained in the two-region solutions. An optimum number of fields was found to be 7 for Pseudo-coupled method.

Keywords

subgrade reaction coefficient, Winkler method, Pseudo-Coupled method, rigid, flexible

KUMLU ZEMİN ÜZERİNDEKİ RADYE TEMELLERİN WİNKLER VE PSÜDO-EŞLENİK YÖNTEMLERİ İLE ANALİZİ

Abstract

Bina temellerinde meydana gelen oturmalar birçok zemin parametresine bağlıdır. Dolayısıyla bu parametreler, hesaplama sürecinde çözümü hem zor hem de karmaşık hale getirmektedir. Bu nedenle, sonlu elemanlar programları, temel çözümünü kolaylaştırmak için zeminin yatak katsayısını kullanır. Zemin yatak katsayısına sahip temel, çözümlerde Winkler yöntemi ve Psüdo-Eşlenik yöntem olmak üzere iki farklı metot kullanılarak çözülmektedir. Winkler yöntemi tek bir alanla çözülebilirken, Psüdo-Eşlenik yöntem 2 veya daha fazla alanla çözülebilir. Bu çalışmada dört farklı kum zemin üzerinde, 36 m x 36 m ölçülerinde kare temelli 10 katlı bir bina ayrı ayrı tasarlanmıştır. Bu zeminlerden ikisi Eurocode 8'e göre C, diğerleri D sınıfındadır. Dört farklı zemin üzerine inşa edilen bu binanın temeli altı farklı bölgeye (bir bölge, iki bölge, üç bölge, beş bölge, yedi bölge, 10 bölge) bölünmüştür. Sonuç olarak, 24 adet analiz ETABS programını kullanarak yapılmıştır. Bu analizler elde edilen sonuçlara göre, rijit temel kabulü için zayıf kum zeminlerde Winkler metodu kullanılması uygun iken, sıkı kum zeminlerde ise Pseudo-coupled metodunun kullanılması daha uygundur. Zayıf kum zeminler üzerine inşa edilen esnek temel çözümlerinde Psüdo-Eşlenik yöntemi kullanılmalıdır. Sıkı kum zeminler üzerine inşa edilen esnek temeller için ise Winkler metodu kullanılmalıdır. Psüdo-Eşlenik yöntemde en yüksek oturmalar iki bölgeli çözümlerde elde edilmiştir. Psüdo-Eşlenik yöntemi için optimum alan sayısı 7 olarak bulunmuştur.

Keywords

Zemin yatak katsayısı, Winkler metot, Psüdo-Eşlenik metot, rijit, esnek

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