Analiza prostokątnego przekroju żelbetowego
The cross-section is rectangular, unilaterally reinforced and loaded by the bending moment and normal compression force. The program verifies a reinforced concrete section using the method of limit deformation (Art. 10.3, Art. 10.4). The maximum allowable strain of concrete in compression is 0,003. Compression reinforcement is not taken into account.
The computed degree of reinforcement is checked using the following expressions (Art. 10.5.1):
Interaction diagram N-M
Usage ratio of concrete cross-section subject to the combination of bending moment and normal force is determined as |0L| / |0R|. Where L is load and R is strength with prescribed eccentricity.
Bending without normal force
The cross-section is rectangular, reinforced on one side and loaded by the bending moment Mu.
The ultimate moment is provided by (Ch. 10, Art. 10.2.7.3, Art. 188.8.131.52):
The limit location of neutral axis is found from:
First, the program computes the ultimate shear strength of concrete Vc (Art. 184.108.40.206).
If the ultimate shear strength of concrete is exceeded, the ultimate shear strength Vmax is checked (Art. 220.127.116.11 + Art. 18.104.22.168).
Next, the necessary reinforcement area is given by (Art. 11.4.7):
where (Art. 11.4.2, Art. 22.214.171.124):