AN APROACH FOR CYCLIC STRESS RATIO OF LIQUEFIED OR UNLIQUEFIED SOILS

Year 2006, Volume: 8 Issue: 2, 79 - 91, 01.05.2006

Osman Uyanık

Abstract

In this paper an alternative analytical relationship is developed that adds soil shear wave
velocities (Vs) and earthquake dominating period (T) to an earthquake and soil parameters
used in the determination of cyclic loads. This relation is named as shear stress ratio (KGO).
KGO is applied to 202 field data and the results are compared in accordance with the results
of mathematical relation (CSR) used before. Consequently, KGO value for liquefied soil is
bigger than CSR. Whereas, KGO value of unliquefied soils is smaller than CSR. A linear
relation is determined between KGO and CSR

Keywords

Shear wave velocity, Cyclic stress ratio, Water-saturated soils, Liquefied soil, Unliquefied soil

SIVILAŞIR YADA SIVILAŞMAZ ZEMİNLERİN YİNELEMELİ GERİLME ORANINA BİR SEÇENEK

Abstract

Bu çalışmada, yinelemeli (tekrarlı) yüklerin belirlenmesi için kullanılan deprem ile zemin parametrelerine, zeminin kayma dalga hızları (Vs) ve deprem dalgasının hakim periyodu da (T) eklenerek alternatif bir analitik ilişki geliştirilmiş ve kayma gerilme oranı (KGO) olarak isimlendirilmiştir. KGO 202 adet alan verisi üzerinde uygulanmış ve sonuçların daha önce kullanılan matematiksel bağıntının (CSR) sonuçlarıyla karşılaştırılmıştır. Sonuç olarak sıvılaşan zeminlerde hesaplanan yinelemeli gerilme oran değerlerinden KGO, CSR’den daha büyük, sıvılaşmayan zeminlerde ise daha küçük olduğu görülmüştür. Ayrıca KGO ile CSR arasında doğrusal bir ilişki belirlenmiştir

Keywords

Kayma dalga hızı, Yinelemeli gerilme oranı, Suya doygun zemin, Sıvılaşır zemin, Sıvılaşmaz zemin

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