بررسی روند تغییر رطوبت و حجم خاک سیلتی غیراشباع در حین تحکیم

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری سازه های آبی، گروه آبیاری و آبادانی، دانشکده کشاورزی و منابع طبیعی، دانشگاه تهران.

2 دانشیار گروه مهندسی آبیاری و آبادانی، دانشکده کشاورزی و منابع طبیعی، دانشگاه تهران.

چکیده

در این پژوهش تغییرات حجم و رطوبت یک خاک سیلتی غیراشباع تحت مکش­های مختلف از طریق انجام آزمایش تحکیم در دستگاه سه محوری مخصوص خاک‌های غیراشباع، مورد بررسی قرار گرفت. آزمایش­ها روی نمونه­های خاک سیلتی تهیه‌شده از روش رسوب‌گذاری در یک دستگاه سه محوری اصلاح‌شده (دستگاه سه محوری با محفظه دوجداره) تحت پنج مکش مختلف در بازه 0 تا 300 کیلوپاسکال انجام شدند. برای ایجاد مکش موردنظر در نمونه از روش انتقال محوری استفاده شد و بارگذاری نمونه تحت مکش ثابت از روش بارگذاری تدریجی صورت گرفت. نتایج نشان می­دهد فشار پیش تحکیمی با افزایش مکش افزایش می­یابد. علاوه بر آن با توجه به نتایج حاصله، ایجاد منحنی تسلیم (LC) در صفحه تنش- مکش امکان‌پذیر است. همچنین بررسی تغییرات شیب و عرض از مبدأ منحنی‌های تحکیم نشان دادند که تغییرات رطوبت و حجم نمونه خاک در خاک‌های غیراشباع تابع تغییرات مکش خاک می‌باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Investigation change trend of moisture and volume of unsaturated silty soil during consolidation

نویسندگان [English]

  • mehrdad moghadas 1
  • ali raeesi estabragh 2
1 Ph.D candidate of water structures, Irrigation and Reclamation department, college of agricultural and natural resources, University of Tehran.
2 Assosiate Prof, Irrigation and Reclamation department, college of agricultural and natural resources, University of Tehran.
چکیده [English]

In this research variation of moisture and volume of an unsaturated silty soil were investigated under different suctions through experimental tests in triaxial apparatus special for unsaturated soils. The tests were carried on specimens of silty soil that made by slurry method in modified triaxial cell (triaxial cell with doubled rings) under 5 suctions from 0 to 300 kPa. Applying the target suction have been done by axis translation technic and loading the specimen under constant suction was carried by using increment loading. The results show that preconsolidation pressure will increase by increasing suction. Furthermore according to the obtained results, creation of yielding curve (LC) in space of stress- suction is possible. Also investigation of variation in slope and intercept of normal compression line showed that variation of volume and moisture of soil is function of suction changes.

کلیدواژه‌ها [English]

  • Consolidation
  • moisture of soil
  • preconsolidation pressure
  • suction
  • Unsaturated Soil
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