بررسی آزمایشگاهی تأثیر تثبیت سیمانی فصل مشترک مسلح‌کننده و ماسه در مقاومت برشی فصل مشترک

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه مهندسی عمران، دانشکده فنی، دانشگاه محقق اردبیلی، اردبیل، ایران

چکیده

فصل مشترک خاک و مسلح کننده پارامتری بسیار تأثیرگذار در تحلیل و طراحی سیستم های خاک مسلح می باشد به‌طوری‌که با تقویت فصل مشترک خاک و مسلح کننده می توان طول مصرفی مسلح کننده‌ی مورداستفاده را تا حد فراوانی کاهش داد.در این تحقیق تغییر ضخامت مسلح کننده مورداستفاده، تأثیر مقادیر مختلف سیمان افزوده‌شده در فصل مشترک خاک و مسلح کننده و همچنین تأثیر تغییر ضخامت مسلح کننده به همراه لایه ی سیمانی به‌صورت آزمایشگاهی با استفاده از آزمایش برش مستقیم در تنش های عمودی50، 100 و 150 کیلو پاسکال بررسی‌شده است. در این آزمایش ها مقادیر متفاوت سیمان بر اساس گرم بر سانتی متر مربع بر فصل مشترک خاک و مسلح کننده اضافه گردید. نمونه های مختلفی باضخامت‌های مختلفی از مسلح کننده که با چسباندن مسلح کننده‌ها با یکدیگر تشکیل‌شده بودند، بررسی شد. بر اساس نتایج آزمایشگاهی، با افزایش ضخامت مسلح کننده از1.13 میلی‌متر به 5.65میلی‌متری مقاومت برشی خاک مسلح بدون تثبیت سیمان در حدود 30درصد افزایش‌یافته است. نتایج بررسی ها نشان می دهد در مقادیر اولیه ی سیمان افزوده‌شده به فصل مشترک خاک و مسلح کننده(0.016 گرم بر سانتی متر مربع )،مشخصات مکانیکی خاک تغییر مشخصی نمی کند ولی با افزودن آن به‌اندازه‌ی مقادیر بیش تر می توان تغییر چشمگیری در مقاومت برشی نمونه ها به‌واسطه‌ی بهبود زاویه اصطکاک ظاهری بین خاک و مسلح کننده مشاهده کرد. قابل‌ذکر می باشد مقاومت برشی فصل مشترک خاک و مسلح کننده در ژئوتکستایل های تثبیت‌شده باسیمان در ضخامت‌های مشابه نسبت به ژئوتکستایل های بدون تثبیت سیمانی، در حدود 46درصد بیشتر می باشد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Laboratory Study of the Effect of Cement Stabilization of the Interface of Reinforcement and Sand on the Interface Shear Strength

نویسندگان [English]

  • Eliar Heidarli
  • Ahad Ouria
Faculty of Engineering, University of Mohaghegh Ardabili.Ardabil.Iran
چکیده [English]

In this study, the effects of the cement stabilization on the interface of the soil and a geotextile, the thickness of the cement and geotextile layer, and the thickness of the geotextile layer on the interface shear strength have been investigated experimentally. In the experiments, a direct shear device with a cylindrical mold with a diameter of 6 cm was used. The geotextile was a woven type. The cement-treated reinforcements were papered by the application of a thin layer of cement with amounts of 0.016, 0.048, 0.08, and 0.112 gr/cm2 on the surface of saturated geotextiles. Geotextiles with different thicknesses were produced by joining several layers of geotextiles using a flexible glue. The interface shear tests have been performed under vertical stresses of 50, 100, and 150 kPa. The results show that adding 0.112 grams/cm2 of cement to the interface of the reinforcements can increase the shear strength of the interface of the samples by 50%, but the amount of cement added should not be less than a certain limit. By comparing the results of tests conducted with different thicknesses of reinforcement with different amounts of cement, it can be concluded that increasing both the cement content and the thickness of the reinforcement increases the shear strength of the interface. By increasing the thickness of the reinforcement, the soil grains are integrated into the reinforcing fabric, produce a rough surface, and increase the shear strength at the interface of the soil and the geotextile.

کلیدواژه‌ها [English]

  • "Cement"
  • "Interface"
  • "Thickness"
  • "Geotextile"
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