Tebriz Metro 2 hattı boyunca sıvılaşmaya bağlı olarak meydana gelen oturma tehlikesi

Öz

Deprem nedeniyle sıvılaşma meydana geldiğinde, zemin katmanlarının çözülmesi içinde bulunan veya yeraltı yapılarına hasar verebilir. Son yirmi yılda, farklı deneysel yöntemler alan ve laboratuvar test verilerine dayandırılarak hacimsel gerilme (zemin oturması) ve maksimum kayma gerginliğini belirlemek için kullanıldı. Bu çalışmanın temel amacı, zemin sıvılaşmasından sonra zemin oturma oranı oranının değerlendirilmesi ve sıvılaşma potansiyel endeksi (LPI) ile oturma arasındaki çalışma ilişkisinin değerlendirilmesidir. Tebriz Metro 2 Hattı boyunca Standard Penetrasyon testi (SPT) 54 sondaj deliğindeki sonuçlarından zemin katmanlarının sıvılaşma potansiyelini tahmin etmek için kullanıldı. Daha sonra hem kuru hem de doymuş zemin katmanlarında sıvılaştırmaya bağlı olarak zemin katmanlarında oturma oranı hesaplanmıştır. Devamında LPI hesaplanmıştır. Çalışmadan elde edilen sonuçlar gösteriyor ki, doymuş zemin katmanlarındaki oturma oranının, yeraltı su seviyesinin üzerindeki zemin katmanlardan belirgin derecede yüksek olduğunu ve zemin katmanlarının yoğunluğunun arttığında oturma oranının ve zemin hacimsel gerilimin azaldığını gösterdi. Ayrıca, zemin katmanlarında LPI ve zemin oturma değerleri arasında iyi bir uyum var.

Anahtar Kelimeler

• Sıvılaşma,Standard penetrasyon testi (SPT),Zemin oturmasi (hacimsel gerilme),Sıvılaşma potansiyel indeksi (LPI),Tabriz Metro 2 hatti

Settlements hazard of soil due to liquefaction along Tabriz Metro line 2

Öz

After the occurrence of liquefaction due to earthquake, the settlement of soil layers damage to structures located on the ground or the underground. In the last two decades, different experimental methods were used to determine the rate of volumetric strain (settlement) and maximum shear strain based on field and laboratory test data. The main purpose of the present study is the evaluation of the rate of settlement after the occurrence of liquefaction in soils and study relationship between liquefaction potential index (LPI) and settlement. The results of the standard resistance penetration test along Tabriz Metro Line 2 used to estimate the liquefaction potential of soil layers in 54 boreholes. Then, the value of settlement in soil layers due to liquefaction in both dry and saturated soil layers were evaluated. In continue, LPI was calculated. The results of this study showed that the rate of settlement in saturated soil layers was remarkably higher than the layers above the underground water level and with an increase in the density of the soil layers, the rate of settlement and soil volumetric strain decreased. Also, there is a good adoption between LPI and settlement values in soil layers.

Anahtar Kelimeler

• Liquefaction,Standard penetration test (SPT),Settlement (volumetric strain),Liquefaction potential index (LPI),Tabriz Metro line 2

Kaynakça

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