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Лекции Сопротивление материалов
.pdfvk.com/club152685050 | vk.com/id446425943
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→ (4) |
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SZ – статический момент «отсеченной части сечения»
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Д. И. Журавский (1855г.) (5) |
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![](/html/46330/238/html_kfajMRh38o.UzY3/htmlconvd-8O8jcp272x1.jpg)
vk.com/club152685050 | vk.com/id446425943 |
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2− 2 |
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, где = . |
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![](/html/46330/238/html_kfajMRh38o.UzY3/htmlconvd-8O8jcp273x1.jpg)
vk.com/club152685050 | vk.com/id446425943
Прямоугольное сечение
![](/html/46330/238/html_kfajMRh38o.UzY3/htmlconvd-8O8jcp274x1.jpg)
vk.com/club152685050 | vk.com/id446425943
Депланация сечения
![](/html/46330/238/html_kfajMRh38o.UzY3/htmlconvd-8O8jcp275x1.jpg)
vk.com/club152685050 | vk.com/id446425943
Квадратное
![](/html/46330/238/html_kfajMRh38o.UzY3/htmlconvd-8O8jcp276x1.jpg)
vk.com/club152685050 | vk.com/id446425943
![](/html/46330/238/html_kfajMRh38o.UzY3/htmlconvd-8O8jcp277x1.jpg)
vk.com/club152685050 | vk.com/id446425943
![](/html/46330/238/html_kfajMRh38o.UzY3/htmlconvd-8O8jcp278x1.jpg)
vk.com/club152685050 | vk.com/id446425943
ПОМЕНЯТЬ Y И Z МЕСТАМИ
= 2 |
2 − 2 |
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2 − 2 |
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2 − 2 = 2 , −2 = 2
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−2 = 2 |
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2 = |
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2 − 2 3Τ2 |
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3 |
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![](/html/46330/238/html_kfajMRh38o.UzY3/htmlconvd-8O8jcp279x1.jpg)
vk.com/club152685050 | vk.com/id446425943
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2 |
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2− 2 3 |
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= 4 |
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2 − 2 = |
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2 2− 2 |
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4 2 |
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1 − |
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1 − |
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В ФОРМУЛАХ (НЕ ИНДЕКСЫ) Y |
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ЗАМЕНИТЬ НА Z |
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3 |
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![](/html/46330/238/html_kfajMRh38o.UzY3/htmlconvd-8O8jcp280x1.jpg)
vk.com/club152685050 | vk.com/id446425943
ПОМЕНЯТЬ ИНДЕКСЫ
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