بررسی آماری و آزمایشگاهی بهسازی یک خاک رسی با استفاده از افزودنی شیمیایی

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه مهندسی آبیاری و آبادانی دانشگاه تهران

چکیده

در این تحقیق اثر یک ماده شیمیایی افزودنی با نام تجاری CBRPLUS در بهسازی یک خاک رسی جنگلی مورد بررسی قرار گرفت. آزمایش های آزمایشگاهی شامل حدود آتربرگ، تراکم استاندارد، CBR (نسبت باربری کالیفرنیا)، تورم آزاد و فشار تورمی روی نمونه خاک طبیعی و خاک حاوی درصدهای وزنی مختلف از ماده افزودنی صورت پذیرفت. نتایج نشان داد که افزودن ماده مذکور بیش از %05/0 به خاک موجب تغییرات قابل ملاحظه ای در خواص فیزیکی و مکانیکی خاک بهسازی شده شامل کاهش حداقل 6% در حد روانی، 9% در اندکس خمیری، 27% در تورم و 45% در فشار تورمی می شود و نیز موجب افزایش حداقل 53% در ظرفیت باربری خاک می گردد، بطوریکه این بهبود خواص تابعی از درصد وزنی ماده CBRPLUS می باشد. علاوه بر آن نتایج آزمایشگاهی مورد تجزیه و تحلیل آماری قرار گرفت و معادلات رگرسیونی چندگانه مناسب جهت مدلسازی و پیش‏ بینی منحنی‏ های CBR، تورم آزاد و فشار تورمی با دقت مناسب و به صورت تابعی از درصد وزنی ماده CBRPLUS، نشانه خمیری و وزن واحد حجم خشک ماکزیمم خاک بهسازی شده ارائه و به تحلیل حساسیت متغیر‏های موثر در مقدار CBR، تورم آزاد نهایی و فشار تورمی پرداخته شد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Statistical and experimental assessment of a clayey soil treated by chemical stabilization

نویسندگان [English]

  • Amin Ghassemi
  • Amin Soltani
  • Ali Raeesi
  • Mohammadhosein Omid
چکیده [English]

This paper presents the results of an experimental program developed to investigate the effect of an additive agent branded CBRPLUS on the mechanical behavior of a forest soil with high plasticity. Various experiments consisting of Atterberg limits, standard compaction, California bearing ratio (CBR), swelling potential and swelling pressure were conducted on natural soil and soil stabilized with various percentages of CBRPLUS. The results indicated that the addition of this material (at the rate of 0.05%), significantly changes the physical and mechanical properties of rehabilitated soil, including, reduction of the liquid limit (at least 6%), plasticity index (at least 9%), swelling potential (at least 27%), and swelling pressure (at least 45%), and also increasing the bearing capacity of soil (at least 53%); hence, the improvement of soil properties is a function of mass percentage of CBRPLUS. Furthermore multiple regression models were developed for CBR, swelling potential and swelling pressure as a function of additive agent percentage, plasticity index and maximum dry unit weight with accuracy and a high degree of agreement between experimental and predicted values. In addition a sensitivity analysis was also performed to investigate the effect of various parameters on CBR, swelling potential and swelling pressure values.

کلیدواژه‌ها [English]

  • Soil Stabilization
  • Bearing Capacity
  • swelling potential
  • Swelling pressure
  • Regression models
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