ارزیابی آزمایشگاهی رفتار ماسه مسلح ‌شده به ژئوگرید قرار گرفته بالای حفرات دوقلو

نوع مقاله : مقاله کامل پژوهشی

نویسندگان

گروه مهندسی عمران، دانشگاه آزاد اسلامی، واحد تهران مرکز، تهران

10.22034/ceej.2024.59826.2313

چکیده

مطالعه حاضر، به بررسی رفتار خاک ماسه‌ای دارای حفرات دوتایی مسلح شده با ژئوگرید مقیاس‌ شده تحت اثر بارگذاری استاتیکی به‌صورت آزمایشگاهی می‌پردازد. تفاوت مهم مطالعه فوق در مقایسه با مطالعات مشابه انجام‌ گرفته در زمینه تسلیح خاک‌های بدون و با حفره، استفاده از مسلح­ کننده‌های مقیاس شده است. تأثیر دانسیته نسبی خاک، فاصله افقی و عمق مدفون‌شدگی حفرات، فاصله عمودی لایه‌های مسلح­ کننده و عمق مدفون‌شدگی لایه اول مسلح­ کننده بر رفتار بار- نشست خاک مسلح شده و جابه ­جایی افقی حفرات مورد بررسی قرار گرفته است. جهت بررسی چگونگی شکل‌گیری گوه‌های گسیختگی، نحوه گسیختگی خاک زیر پی و میزان کرنش برشی پدید آمده در اثر اعمال بار در محل گوه‌های گسیختگی از روش سرعت­ سنجی تصویری ذرات (PIV) استفاده ‌شده است. ارزیابی نتایج به‌دست ‌آمده نشان داد که با افزایش فاصله عمودی مسلح ­کننده‌ها و عمق مدفون‌شدگی لایه اول مسلح ­کننده، سربار قرار گرفته بر روی مسلح کننده‌ها و مقاومت اصطکاکی بین مسلح ­کننده‌ها و خاک ماسه‌ای افزایش ‌یافته و متعاقب آن ظرفیت باربری خاک ماسه‌ای با حفرات دوتایی مسلح شده افزایش‌ یافته است. همچنین، نتایج بیانگر این بود که تسلیح خاک متراکم با دو لایه ژئوگرید باعث افزایش ظرفیت باربری خاک ماسه‌ای متراکم با حفرات دوتایی مسلح شده به ­میزان 8/51% در مقایسه با خاک ماسه‌ای متراکم با حفرات دوتایی بدون مسلح­کننده شده است. در نهایت، ارزیابی خروجی‌های تحلیل PIV نشان‌دهنده این موضوع بود که نرخ کرنش برشی شکل‌ گرفته در اثر بارگذاری در محل گوه گسیختگی زیر پی با افزایش تعداد لایه‌ها و عمق مدفون‌شدگی لایه اول مسلح ­کننده، کاهش‌ یافته است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental Evaluation of The Behavior of Geogrid-Reinforced Sand Placed on Top of Twin Voids

نویسندگان [English]

  • Pantea Pezeshkian
  • Michael Kazemzadeh
  • Amir Ali Zad
  • Maryam Yazdi
Department of Civil Engineering, Faculty of Civil and Earth Resources Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran
چکیده [English]

Foundation settlement is influenced by a number of variables, including soil type, structure load, environmental influences, and subsurface voids. Whether human-made or natural, underground voids can significantly reduce the soil's load-bearing capacity, leading to excessive settlement and possible structural damage. Using stabilizing elements to reinforce soil is an effective way of reducing these effects and improving soil capacity. Studies on the performance of foundations over twin voids, particularly in reinforced soil, are still limited, despite the fact that most prior research has concentrated on foundation behavior over a single void. The behavior of a strip foundation lying on sandy soil reinforced with geogrid and featuring twin voids is examined in this study. Moreover, failure surfaces were investigated using the Particle Image Velocimetry (PIV) method.

کلیدواژه‌ها [English]

  • Reinforced sand
  • Geogrid
  • Experimental modeling
  • Voids
  • Relative density
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