ВЛИЯНИЕ СКОРОСТИ СДВИГА НА ПРОЧНОСТНЫЕ ХАРАКТЕРИСТИКИ ПЕСЧАНЫХ ГРУНТОВ SHEAR RATE EFFECT ON SHEAR STRENGTH CHARACTERISTICS OF SANDY SOILS
Аннотация
Проведено исследование влияния скорости сдвига при прямых испытаниях на сдвиг на прочностные характеристики песка различного гранулометрического состава. Испытания проводились при девяти различных скоростях сдвига в диапазоне от 0,05 до 5 мм/мин при нормальных напряжениях 54,5; 109 и 218 кПа. Образцы испытывались при различных условиях замачивания. Результаты показали, что с ростом скорости сдвига увеличиваются угол внутреннего трения и пиковая прочность на сдвиг. Увеличение углов внутреннего трения и
пиковой прочности особенно заметно при скоростях более 1 мм/мин. Несмотря на то, что влияние размера зерна на изменение прочностных параметров (изза скорости сдвига) ограничено для грунтов, рассмотренных в данном исследовании, этот эффект также следует учитывать.
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