MONONOBE–OKABE YÖNTEMİNDE SİSMİK TOPRAK BASINCI KATSAYILARINI ETKİLEYEN PARAMETRELERİN DUYARLILIK ANALİZİ

Öz

Dayanma yapılarında deprem etkisi altında meydana gelen toprak basınçlarının doğru belirlenebilmesi, geoteknik tasarım güvenliği açısından kritik öneme sahiptir. Bu çerçevede Mononobe–Okabe yöntemi, sismik aktif ve pasif toprak basıncı katsayılarının belirlenmesinde sık olarak başvurulan yaklaşımlardan biridir. Bu çalışmada, Mononobe–Okabe yöntemi dahilinde sismik toprak basıncı katsayılarını etkileyen temel parametrelerin duyarlılığı araştırılmıştır. Analizlerde zemin içsel sürtünme açısı (φ′d), duvar arka yüz açısı (ψ), dolgu yüzeyi eğimi (β), duvar-zemin sürtünme açısı (δd), kısa periyot tasarım spektral ivme katsayısı (SDS) ve dayanma yapısı azaltma katsayısı (r) dikkate alınmıştır. Hazırlanan 2160 farklı senaryo için toplam aktif katsayı (Kat), toplam pasif katsayı (Kpt), dinamik aktif artış katsayısı (Kad) ve pasif dirençteki dinamik azalma katsayısı (Kpd) hesaplanmış; parametrelerin katsayılar üzerindeki etkileri kıyaslanarak değerlendirilmiştir. Bulgular, aktif basınç katsayıları üzerinde özellikle β ve SDS parametrelerinin; pasif basınç katsayıları üzerindeyse φ′d ve β parametrelerinin daha belirgin etkiye sahip olduğunu göstermiştir. Sonuçlar, Mononobe–Okabe katsayılarının sadece deprem parametrelerine değil, aynı zamanda zemin ve geometriye ilişkin girdilere de yüksek duyarlılık gösterdiğini ortaya koymaktadır.

Anahtar Kelimeler

• Mononobe–Okabe yöntemi
• Sismik toprak basıncı
• Duyarlılık analizi
• Dayanma yapıları

Etik Beyan

Bu çalışmanın özgün olduğunu, çalışma sürecinin tüm aşamalarında bilimsel etik ilke ve kurallarına uyulduğunu, kullanılan tüm kaynaklara metin içinde ve kaynakçada yer verildiğini beyan ederim.

SENSITIVITY ANALYSIS OF PARAMETERS AFFECTING SEISMIC EARTH PRESSURE COEFFICIENTS IN THE MONONOBE-OKABE METHOD

Öz

Accurate determination of soil pressures under seismic influence in retaining structures is critically important for geotechnical design safety. In this context, the Mononobe–Okabe method is one of the frequently used approaches for determining seismic active and passive soil pressure coefficients. In this study, the sensitivity of the fundamental parameters affecting seismic soil pressure coefficients within the Mononobe–Okabe method was investigated. In the analyses, the soil internal friction angle (φ′d), wall back face angle (ψ), fill surface slope (β), wall-soil friction angle (δd), short-period design spectral acceleration coefficient (SDS), and retaining structure reduction coefficient (r) were considered. For 2160 different scenarios, the total active coefficient (Kat), total passive coefficient (Kpt), dynamic active increase coefficient (Kad), and dynamic reduction coefficient in passive resistance (Kpd) were calculated; and the effects of the parameters on the coefficients were compared and evaluated. The findings showed that the parameters β and SDS had a more significant effect on active pressure coefficients, while the parameters φ′d and β had a more significant effect on passive pressure coefficients. The results reveal that Mononobe–Okabe coefficients exhibit high sensitivity not only to earthquake parameters but also to soil and geometry-related inputs.

Anahtar Kelimeler

• Mononobe–Okabe method
• Seismic earth pressure
• Sensitivity analysis
• Retaining structures

Etik Beyan

I declare that this study is original, that all stages of the study were conducted in accordance with scientific ethical principles and rules, and that all sources used were cited in the text and listed in the references.

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