مطالعه آزمایشگاهی رفتار شیروانی مسلح شده در شرایط غیراشباع

نوع مقاله: مقاله پژوهشی

نویسندگان

1 گروه مهندسی عمران، واحد نجف‌آباد، دانشگاه آزاد اسلامی، نجف‌آباد، ایران.

2 گروه مهندسی عمران، دانشگاه صنعتی اصفهان، ایران.

3 گروه آب و محیط‌زیست، مجتمع عالی آموزشی و پژوهشی صنعت آب و برق اصفهان، وزارت نیرو، اصفهان، ایران.

10.22091/cer.2021.6444.1234

چکیده

ساخت پی یا خاکریز جاده بر روی بستر خاک نرم، به علت کم بودن ظرفیت باربری معمولاً سبب بروز گسیختگی بستر توأم با نشست زیاد می‌گردد. تسلیح خاک با استفاده از ژئوسل به عنوان یک راه حل مناسب توسط محققین مختلف ارائه شده است. در پژوهش حاضر به منظور بررسی رفتار شیروانی مسلح با تغییر جایگاه ژئوسل و همچنین تغییر در درصد رطوبت خاک آزمایش‌هایی انجام شده است. در مجموع، هفت نمونه آزمایشگاهی طراحی و ساخته شده که برنامه آزمایش‌ها با توجه به دو متغیر طراحی شده‌اند. این دو متغیر عبارتند از مسلح کننده (ژئوسل) و درصد رطوبت. برای درصد رطوبت مقادیر 10%، %۱5 و ۲۰% در نظر گرفته شد و ژئوسل در دو حالت میانی (u/h=0.5) و انتهایی شیروانی (u/h=1) مورد بررسی قرار گرفت. نتایج به‌دست آمده تأثیر مثبت وجود ژئوسل را با توجه به مکانیزم عملکرد سه‌گانه ژئوسل در توده خاک مسلح، بیان می‌کند. از نتایج به‌دست آمده اینگونه تعیبر می‌گردد که با افزایش مکش خاک و ثابت بودن محل قرارگیری لایه ژئوسل، تغییرات جابه‌جایی در حدود 30 درصد کاهش یافته، اما با تغییر محل لایه ژئوسل (u/h=1 به u/h=0.5) در رطوبت ثابت مقدار کاهش نشست و جابه‌جایی شیروانی در حدود 15 درصد می‌باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Laboratory Study of Reinforce Slop Behavior in Unsaturated Conditions

نویسندگان [English]

  • Behnam Mehdipour 1
  • Bahram Nadi 1
  • Hamid Hashemalhosseini 2
  • Masuod Mirmohammadsadeghi 3
1 Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran.
2 Civil Engineering Group, Is-fahan university of technol-ogy, Isfahan, Iran
3 Departeman of Water and Natural Environment, Isfahan Higher Education and Research Institute (IHEARI); Mimistry of Energy, Isfahan, Iran.
چکیده [English]

Construction of road foundations or embankments on soft soil bed, due to bearing capacity, usually causes bed rupture with high subsidence. Soil reinforcement using geocell has been proposed by various researchers as a suitable solution. In the present study, experiments have been performed to investigate the behavior of armed slopes by changing the geocell position as well as the change in the percentage of soil moisture. A total of seven laboratory samples were designed and built, and the test program was designed according to two variables. These two variables are reinforcement (geocell) and moisture content. For moisture content, the values of 10%, 15%, and 20% were considered, and the geocell was examined in both the middle, and end modes of the work. The results show the positive performance of Geocell in increasing shear strength, load-bearing and flexural strength, and finally reducing displacement and increasing gable stability. The positive effect of geocell presence can be expressed according to the triple action mechanism of geocell in the reinforced soil mass. The results show that with increasing soil suction with the location of the geocell layer is constant, the displacement changes are reduced by about thirty percent, but by changing the location of the geocell layer (u/h=1 to u/h=0.5) in constant moisture, the amount decreases. Settlement and displacement is about fifteen percent.

کلیدواژه‌ها [English]

  • unsaturated soil
  • slop
  • Geocell
  • physical model
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