نویسندگان

دانشگاه تربیت مدرس

چکیده

 در این مقاله، مدل شبکه- دانه مجزای بتن برای در‌نظر گرفتن سنگدانه‌های غیردایروی در حالت دو‌بعدی توسعه یافته است. به این منظور از معادله انعطاف‌پذیر ابربیضی برای تولید سنگدانه‌ها استفاده شده تا امکان شبیه‌سازی طیف گسترده‌تری از نمونه‌ها در فضای دوبعدی به مدل شبکه-دانه مجزا اضافه شود. متناسب با این توسعه، رویه‌های لازم برای تولید سنگدانه‌ها، چینش آنها در فضا، تعیین ناحیه اثر هر سنگدانه، تعیین سطوح اندرکنشی و نقاط محاسباتی و محاسبه کرنش‌ها تشریح می‌شود. در پایان، اثر هندسه سنگدانه‌ها بر مقاومت فشاری و منحنی نرم‌شوندگی بزرگ ‌مقیاس بتن و همچنین الگوی ترک‌خوردگی بتن در تحلیل تک‌محوری فشاری مورد بررسی قرار گرفته است.‏

کلیدواژه‌ها

عنوان مقاله [English]

Extending Lattice Discrete Particle Model of Concrete for Non-circular Aggregates

نویسندگان [English]

  • M. Kamza
  • M. Safarnejad
  • S. Shahbeyk

چکیده [English]

In this paper, Lattice-Discrete Particle Model (LDPM) of concrete has been extended in 2-D to account for the effect of non-circular aggregates. To this end, the flexible equation of super-ellipse is employed for generating aggregates in order to add the simulation possibility of a greater spectrum of aggregate samples in 2-D to lattice-Discrete particle Model. Alongside this extention, required procedures for the generation of aggregates, their packing in space, the determination of influencing region of each particle, the definition of interacting surfaces and computational points and the definition of strains are outlined. Finally, the effects of aggregates geometry on macro-scale compressive strength and softening curve and also cracking pattern of concrete under uniaxial compression are discussed.

کلیدواژه‌ها [English]

  • Lattice-Discrete Particle Model (LDPM)
  • Concrete
  • meso-structure
  • super-ellipse
  • cracking
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