Влияние смещения точки приложения нагрузки на результаты испытаний на трехточечный изгиб: оценка погрешности и коррекция

Предложена усовершенствованная методика проведения и обработки данных испытаний на изгиб. Выведены выражения для относительной погрешности стандартных формул для определения максимальных изгибающего момента и прогиба под действием силы, максимальных напряжения и деформации, предела прочности и деформации при разрушении в испытаниях на трехточечный изгиб в зависимости от относительного смещения точки приложения нагрузки от середины пролета. Доказано, что при любом значении нагрузки стандартные формулы (не учитывающие смещение точки приложения) завышают напряжение, предел прочности и модуль упругости и занижают предельную деформацию. Указано, в каких случаях этой систематической погрешностью можно пренебречь. Выведены формулы для их коррекции при малом пролете.
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