مطالعۀ آزمایشگاهی تأثیر اندازۀ دانه بر مدول برشی کرنش-کوچک خاک‌های دانه‌ای

نوع مقاله : پژوهشی

نویسندگان

1 دانشگاه رازی کرمانشاه

2 رازی کرمانشاه

چکیده

در محدودۀ کرنش‌های کوچک سرعت موج‌برشی و متعاقب آن مدول برشی یکی از پارامترهای مهم شناخت خواص دینامیکی خاک است. در این راستا موضوع شناخت تأثیر اندازۀ دانه­ها خاک بر سرعت موج‌برشی یکی از مسائل مهم است. بررسی محقّقین در گذشته نشان‌دهندۀ تأثیر متفاوت اندازۀ دانه­های خاک بر مدول ‌برشی است. هدف این پژوهش بررسی اثرات طیف گسترده‌ای از اندازۀ دانه­های روی مدول برشی در خاک­های خشک شن و ماسه با استفاده از دستگاه المان خمشی تعبیه‌شده در سلول سه محوری است. نتایج نشان‌دهندۀ حساسیت مدول برشی به تغییرات اندازۀ دانه­های خاک است، به‌طوری‌که در بازه‌ای از اندازۀ دانه­های خاک با افزایش اندازۀ قطر دانه­ها، مدول برشی افزایش و در بازۀ دیگر با افزایش اندازۀ قطر دانه­ها مدول برشی کاهش می­یابد.

کلیدواژه‌ها


عنوان مقاله [English]

An Experimental Study on the Influences of Particle Size on Small-Strain Shear Modulus of Granular Soils

نویسندگان [English]

  • Mohammad SHARIFIPOUR 1
  • Abolhassan sharifi 2
  • Amir Rizvandy 2
1 Razi University of Kermanshah
2 Razi University of Kermanshah
چکیده [English]

Under small strains, the shear-wave velocity (Vs) and its resultant maximum shear modulus (Gmax) are important parameters in geotechnical engineering soil dynamics analyses. In this regard, the evaluation of the influences of soil particle size on the dynamic behavior of soils during wave propagation has been an important issue in geotechnical engineering. According to the relevant literature, the influences of grain size on shear wave velocity of soil were completely different in various research studies. This research aims to experimentally examine the effects of a wider range of particle sizes, on maximum shear modulus in dry sandy soils, using a bender element apparatus embedded in a triaxial cell. The results indicated that maximum shear modulus of sand was considerably affected by changes in grain size so that in a particular range of grain size, shear modulus increased as the diameter of soil grains rose, while, in the other range, maximum shear modulus diminished with increasing grain diameter.

کلیدواژه‌ها [English]

  • Shear wave velocity
  • Granular soil
  • Bender element test
  • Maximum shear modulus
  • Small-strain behavior
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