Limit states. Load and impact.

Limit states.

Load and impact.

Under the limit understand this state of the design, after which further operation is impossible,

due to loss of ability to resist external loads or as a result of large deflection or external damage. In accordance with this, 2 groups of limit states are established:

I - calculation of bearing capacity;

II - calculation for unsuitability to normal operation.

The calculation for the I group of limiting states is performed in order to prevent the destruction of the structure (strength calculation), loss of stability of the structure shape (calculation for longitudinal bending).

- calculation of strength.

- calculation of sustainability.

- longitudinal section coefficient or stability coefficient.

This calculation is performed to prevent the destruction of the structure.

(calculation on durability) or loss of stability of a structure (calculation on a longitudinal bend).

Calculation for group II limit states.

This calculation has the goal to prevent the development of excessive deformations (deflections), to exclude the formation of cracks or to limit the width of their disclosure.

The calculation for the first group of limiting states is basic and is used in the selection of sections. The calculation for group II is carried out for those structures that, being durable, lose their performance due to excessive sagging, cracking or excessive opening, leading to premature corrosion of the reinforcement.