روشهای عددی در مهندسی

نویسندگان

دانشکده مهندسی عمران، دانشگاه تبریز، تبریز

https://doi.org/10.29252/jcme.38.1.101

چکیده

معادلات بیوت که اندرکنش سیال و خاک را به‌طور همزمان درنظر می‌گیرند از کاربردی‌ترین روابط موجود در تحلیل روان‌گرایی محیط‌های متخلخل هستند. اما به‌دلیل افزایش ناگهانی اضافه فشار در اثر تحریک لرزهای و وقوع گرادیان‌های هیدرولیکی بالا، فرض جریان دارسی به‌کار رفته در این معادلات مورد تردید قرار می‌گیرد. در بررسی حاضر در معادلات u-p جریان از نوع غیردارسی (دارسی معادل) درنظر گرفته شده، رفتار غیرخطی خاک نیز با مدل پاستور- زینکویچ- چان مدل میشود. برای صحتسنجی آزمایش شماره یک VELACS مدل‌سازی شده و اثر فرض غیرخطی جریان سیال روی نتایج بررسی شده است. در ضرایب نفوذپذیری کم نتایج حاصل از جریان غیردارسی و دارسی بر هم منطبق هستند ولی در ضرایب نفوذپذیری بالا، به‌خصوص در زمانهای ثانویه واعماق بیشتر، از هم فاصله می‌گیرند.

کلیدواژه‌ها

dor

20.1001.1.22287698.1398.38.1.5.6

عنوان مقاله [English]

Dynamic Analysis of Porous Media using Generalized Plasticity Model and Non-Darcy Flow Rule

نویسندگان [English]

F. Kalateh
F. Hosseinejad

چکیده [English]

Biot equations that consider fluid and soil interaction at the same time are the most applicable relationships in the soil dynamic analysis. However, in dynamic analysis, due to the sudden increase in the excess pore pressure caused by seismic excitation and the occurrence of high hydraulic gradients, the assumption of the Darcy flow used in these equations is questionable. In the present study, in the u-p form of Biot equations, non-Darcy flow is considered. Also, the nonlinear behavior of soil is modeled by the Pastor-Zienkiewicz -Chan model. For validation, the VELACS No.1 experiment is modeled and the effect of the nonlinear fluid flow assumption on the results is examined. The results indicate that in the low permeability coefficients, the obtained results of the non-Darcy and Darcy flow are in agreement; however, in high permeability coefficients, these two methods differ by time and depth.

کلیدواژه‌ها [English]

Dynamic analysis
Coupled equations
Generalized plasticity
Non-Darcy flow

مراجع

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