استفاده از روش تراکم کاهش ‌یافته در نمونه‌سازی خاک ماسه کربناتی لای‌دار بوشهر

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده فنی و مهندسی، دانشگاه بین المللی امام خمینی (ره)، قزوین، ایران

2 دانشکده فنی و مهندسی، دانشگاه بین المللی امام خمینی (ره،) قزوین، ایران

چکیده

ساخت نمونه‌های همگن دارای نسبت تخلخل یکسان در ارتفاع نمونه در آزمایش سه محوری استاتیکی و سیکلی بسیار مهم می‌باشد زیرا پارامتر نسبت تخلخل بر روی مقاومت نمونه‌های ماسه‌ای به‌ویژه مقاومت روانگرایی تأثیرگذار است. روش تراکم کاهش‌یافته توسعه‌یافته روش تراکم مرطوب است که برای ساخت نمونه همگن در خاک‌های ماسه با ریزدانه روش بسیار مناسبی می‌باشد. در این تحقیق روش تراکم کاهش‌یافته برای نمونه‌سازی در خاک ماسه لای دار کربناتی بوشهر مورداستفاده قرارگرفته و به‌منظور کنترل همگن بودن نمونه در لایه‌های مختلف از روش تزریق ژلاتین استفاده می‌شود. به‌منظور بررسی تأثیر لای بر کیفیت نمونه‌های ساخته‌شده ماسه‌ای با درصد لای 0 تا 40% درروش تراکم کاهش‌یافته و رسیدن به یک نمونه همگن تعدادی آزمایش تزریق ژلاتین در نمونه‌های ماسه لای دار کربناتی بوشهر انجام‌شده است. نتایج نشان می‌دهد که با استفاده از تراکم کاهش‌یافته نمونه‌سازی همگن در ماسه کربناتی بوشهر امکان‌پذیر است. با تغییر در درصد لای مقدار پارامتر درصد کاهش تراکم لایه اول (Un مناسب) تغییر می‌کند. پارامتر Un در درصد لای های کمتر (0، 10 و 20%) به 4 و 6% محدود می‌شود و در درصد لای بالاتر (30 و 40%) به مقدار 6 و 8% افزایش می‌یابد. می‌توان نتیجه گرفت که در درصد لای های کمتر، ذرات لای در بین حفرات ماسه جای می‌گیرند و این امر باعث می‌شود که لایه اول با درصد کاهش تراکم کمتری به تراکم هدف نزدیک شود.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Under-compaction method for sample preparation of Boushehr carbonated silty sand

نویسندگان [English]

  • Elham Ghanbari Alamouti 1
  • Reza Ziaie Moayed 2
  • Seyed Abolhasan Naeini 2
1 Department of Geotechnical Engineering, Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran
2 Department of Geotechnical Engineering, Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran
چکیده [English]

Because of the impact of the void ratio parameter on liquefaction and static strength of sandy soils, the preparation of samples which are homogenous in their heights in monotonic and cyclic triaxial tests is an important issue. The under-compaction method is an extended preparation method of wet tamping that is a suitable procedure to make homogenous sandy soil with fines. In this research, the under-compaction method is used in order to prepare samples of carbonated silty sand from Boushehr port and a method called injection of gelatin solution is used to control the homogeneity of samples. In order to investigate the effect of silt content on the homogeneity of prepared samples, Boushehr carbonated sand is mixed with silt percent of 0 to 40%, and gelatin solution is injected into the samples. Results show that samples prepared with the under-compaction method are homogenous, also the variation of silt content, changes the parameter of reduced compaction percent of the first layer (Un). In silt percents 0 to 20%, the Un parameter is limited to 4 and 6%, and in silt percent of 30 to 40%, the Un parameter is obtained 6 and 8%. It can be concluded that in silt percent of 0, 10 and 20%, inter-granular voids of sandy soil are filled with silt particles, thus the first layer is compacted close to the desired density, and the final compacted sample is more homogenous than the samples with higher percent of silt.

کلیدواژه‌ها [English]

  • Carbonated silty sand
  • Gelatin injection method
  • Under-compaction method
  • Silt content
  • Homogenous sample

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نشریه مهندسی عمران امیرکبیر
دوره 54، شماره 9
آذر 1401
صفحه 3243-3262

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