RF-CONCRETE NL | Design
The nonlinear deformation analysis is performed by an iterative process considering the stiffness in cracked and non-cracked sections. The nonlinear reinforced concrete modeling requires definition of material properties varying across the surface thickness. Therefore, a finite element is divided into a certain number of steel and concrete layers in order to determine the cross-section depth.
The mean steel strengths used in the calculation are based on the "Probabilistic Model Code" published by the JCSS technical committee. It is up to you if the steel strength is increased until the ultimate tensile strength is reached (increasing graph in the plastic range). Regarding material properties, it is possible to control the stress-strain diagram of the compressive and tensile strength. For the concrete compressive strength, you can select a parabolic or a parabolic-rectangular stress-strain diagram. On the tension side of the concrete, it is possible to deactivate the tensile strength as well as to apply a linear-elastic diagram, a diagram according to the CEB-FIB model code 90:1993, and concrete residual tensile strength considering the tension stiffening between the cracks.
Furthermore, you can specify which result values should be displayed after the nonlinear calculation at the serviceability limit state:
- Deformations (global, local based on non-/deformed system)
- Crack widths, depths, and spacing of the top and bottom side in principal directions I and II
- Stresses of the concrete (stress and strain in principal direction I and II) and of the reinforcement (strain, area, profile, cover, and direction in each reinforcement direction)
RF-CONCRETE Members:The nonlinear deformation analysis of beam structures is performed by an iterative process considering the stiffness in cracked and non-cracked sections. The material properties of concrete and reinforcing steel used in the nonlinear calculation are selected according to a limit state. It is possible to apply the composite action of concrete tensile strength between the cracks (tension stiffening) using a modified stress-strain diagram of reinforcement steel, or the concrete residual tensile strength.
Physical and geometrical nonlinear calculation of beam and plate structures consisting of reinforced concrete