تخمین پارامترهای طراحی ژئوتکنیکی خاک بهسازی‌شده به‌روش پیش‌بارگذاری بااستفاده از نتایج ابزارگذاری و روش عددی- مطالعۀ موردی

نوع مقاله : پژوهشی

نویسندگان

• خسرو مهرشاهی
• حمید علی الهی

دانشگاه آزاد واحد زنجان

10.22067/civil.v1i30.52137

چکیده

در این مقاله بااستفاده از آنالیز برگشتی حاصل از نتایج ابزاردقیق و به‌کمک روش عددی، به برآورد پارامترهای تأثیرگذار در روند طراحی عملیات پیش‌بارگذاری با خاکریز به‌همراه زهکش‌های قائم (PVDs) پرداخته شده است. بهعنوان مطالعۀ موردی، پروژۀ انبار نفت ماهشهر واقع در بندر ماهشهر درنظر گرفته شده است. برای کنترل نتایج محاسبات و عملکرد مناسب خاکریزها از ابزارهایی دقیق‌ نظیر نشست‌سنج‌ها و پیزومترها که در تمامی نقاط خاکریز نصب شده‌اند، بهره گرفته‌شده است. نتایج نشان می‌دهد که پارامتر‌های آزمایشگاهی درنظر گرفته شده برای محاسبات اولیۀ نشست تحکیمی خاک کمتر از مقادیر واقعی اندازه‌گیری‌شده درنظر گرفته‌شده است. درنهایت مقادیر نشست تخمینی مخزن نفت مربوط در قبل و پس از بهسازی خاک مورد مقایسه قرار گرفته است که نتیجۀ حاصل حاکی از عملکرد مناسب عملیات پیش‌بارگذاری خاک در پروژۀ حاضر می‌باشد.

کلیدواژه‌ها

• پیش‌بارگذاری
• زهکش‌های شعاعی
• نشست تحکیمی
• زمان تحکیم، روش عددی

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عنوان مقاله [English]

Estimating the Geotechnical Design Pararameters of Improved Soil by Preloading Method Using Instrumentation Results and Numerical Approach- a Case Study

نویسندگان [English]

• Khosrow Mehrshahi
• Hamid Alielahi

Islamic Azad University

چکیده [English]

In his paper, back-analysis using rsults from instrumentation by finite element software for design of preloading method by embankment with prefibricated vetical drains (PVDs) was used, and the results were compared with each other. Hence, the basic geotechnical parameters obtained by laboratory and field experiments have been modified using this method. In this regard, the Mahshahr oil storage project has been used as a case study. All of the methods that are used for improving soil must ultimately result in increased soil resistance parameters, reduced compressibility, and reduced soil permeability. The soil improvement technique using preloading was used in Mahshahr where there are soft soil layers beneath higher than sub-surface water. control performance of the embankments, some instruments such as Settlement Plates and Piezometers have been used. The results obtained from the analysis shows that settlement parameters obtained from the instruments data by back-analysis were less than primary consolidation settlement parameters based on laboratory tests. Finally, soil settlement estimation of the oil tank was compared before and after preloading, and it was found that using this method for soil improvement can be very efficient in the current project.

کلیدواژه‌ها [English]

• Preloading Method
• Radial Drains
• Consolidation Settlement
• Numerical Approach

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