Design of Longitudinal Reinforcement for Slabs
The design of reinforcement is performed for load caused by the bending moment Mrd. The program provides the required area of tensile and compressive (if needed) reinforcement. It takes into account conditions for the minimum and maximum degree of reinforcement in a given cross-section. First, the program determines the location of the neutral axis as:
Providing the location of the neutral axis is less than the allowable one (x < xmax), the program determines the area of tensile reinforcement Ast from the expression:
Providing the location of the neutral axis is greater than the allowable one (x > xmax), the program determines the areas of both compressive Asc and tensile Ast reinforcement from the expressions:
The limit location of the neutral axis is found from:
xmax = 0.53d | for steel Fe 250 |
xmax = 0.48d | for steel Fe 400 |
xmax = 0.46d | for steel Fe 500 |
The computed degree of reinforcement is checked using the following expressions:
If the maximum degree of tensile reinforcement (ρt,max = 0.04) or total reinforcement (ρmax = 0.08), respectively, is exceeded, the program informs the user that the longitudinal reinforcement cannot be designed for a given cross-section.