نویسنده
گروه عمران، دانشکده فنی مهندسی، دانشگاه گیلان
چکیده
فرایند تشکیل خاک‌های چسبنده باعث شکل‌گیری ناهمسانی و ناهمگونی در پارامترهای مقاومتی و سختی آنها می‌شود. اغلب خاک‌ها در حالت طبیعی هم ناهمسانی نسبت به مقاومت برشی و هم ناهمگونی نسبت به عمق از خود نشان می‌دهند. در این مقاله برای درنظر گرفتن اثر ناهمسانی چسبندگی خاک مدل استاندارد موهر- کلمب به حالت ناهمسان تعمیم داده شده است. از این‌رو با استفاده از تئوری حوزه تصادفی در ترکیب با روش تفاضل محدود و در چارچوب شبیه‌سازی‌های مونت‌کارلو و با درنظر گرفتن اثر خود همبستگی و همبستگی متقابل بین پارامترهای مقاومتی خاک، ظرفیت باربری پی‌های سطحی در فضای کاتوره‌ای محاسبه شده و مشاهده شد که ظرفیت باربری پی‌های سطحی با افزایش تغییرپذیری پارامترهای مقاومتی کاهش و با افزایش نسبت‌های ناهمسانی افزایش می‌یابد.
کلیدواژه‌ها
عنوان مقاله [English]
The Effect of Mechanical Anisotropy and Heterogeneity of Shear Strength Parameters of Soils on Drained Bearing Capacity of Shallow Foundations
نویسنده [English]
- R. Jamshidi Chenari
چکیده [English]
Natural formation of soil deposits causes heterogeneity and anisotropy in their strength and stiffness properties. However, most soils in their natural states exhibit some anisotropy with respect to shear strength and heterogeneity with respect to the depth. In this paper, the standard Mohr- Coulomb constitutive law is generalized to anisotropic version in order to consider the effect of cohesion anisotropy of soil. Random field theory coupled with finite difference method was utilized in Monte Carlo simulations with considering the effect of auto-correlation and cross correlation between strength parameters of soil, in order to calculate the bearing capacity of shallow foundation in a strain controlled scheme. The results showed that the bearing capacity of shallow foundation decreases with increasing in variability of strength parameters and increases with increasing in anisotropy ratio.
کلیدواژه‌ها [English]
- Mechanical anisotropy
- Heterogeneity anisotropy
- Bearing capacity
- Shallow foundations
- Spatial variability
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