CODECHECK: Checks (ULS + SLS)

Perform all required checks in the ULS (ultimate limit state) and SLS (ultimate serviceability state) according to Eurocode

This includes the checks due to bending, shear and torsion, as well as interaction due to shear + torsion and the check against brittle failure in the ULS (ultimate limit state), and the stress limitation checks and the check for the limitation of the crack widths in the SLS (serviceability limit state).

The checks are performed based on the given envelopes for the elements assigned by assemblies and the respective results are stored under the given result name.

The possibly already existing amounts of reinforcement are considered (greater values from user-defined and evaluated reinforcement).

Note: The user-defined amounts of reinforcement can be defined in the respective property sets in the cross section definition. The stress checks and the crack check can only be performed, if the exposure zones for determining the respective exposure class are defined within the cross section definition.

Parameters

Day (day)

Day in the construction phases at which the check should be performed

Result name (resname)

Result name; user-defined name under which the various results of the checks should be stored

Type of check

Flexure (flexure)

Option to perform the design due to bending (moment and normal force)

Brittle failure (brittle)

Option to perform the design against brittle failure

Shear (shear)

Option to perform the design due to shear (as well as the design of the joints in composite structures, particularly between concrete surfaces of different age)

Torsion (torsion)

Option to perform the check due to torsion

Interaction (interact)

Option to perform the check due to interaction of shear + torsion

Stress limitation

Option for performing the checks for stress limitation

Crack control (crack)

Option to perform the design in regard to the limitation of crack widths

Detailing (detailing)

Option to apply detailing rules for reinforcement

Additional parameters and inputs

Theta (theta)

Angle used in the shear and torsion design based on the variable angle truss model

ULS Combinations and Groups

ULS (env)

Name of the envelope/combination/combination group for which the design in the ULS should be performed

SLS Combinations and Groups

Characteristic (env1)

Name of the envelope/combination/combination group which should be taken as the characteristic combination for the respective design in the SLS

Frequent (env2)

Name of the envelope/combination/combination group which should be taken as the frequent combination for the respective design in the SLS

Quasi-permanent (env3)

Name of the envelope/combination/combination group which should be taken as the quasi-permanent combination for the respective design in the SLS

Rare (env4) [only if DIN EN is selected]

Name of the envelope/combination/combination group which should be taken as the rare combination for the respective design in the SLS

The evaluated results can be addressed by their result names in the result presentation (tab Design Checks in the Result Data in Results).

Calculation assumptions for the checks in the ULS:

• Non-linear material behavior (stress-strain diagrams according to the standard)
• Tensile stresses in the concrete are not considered.
• The strain of bonded reinforcement is equal to the strain of the surrounding concrete.
• Transformed cross sections are considered: Net cross section (i.e. minus duct areas) until the grouting of the ducts, i.e. until the task TENSION or the calculation task GROUT is performed. The stiffness of the steel area of the tendons is considered after performing these tasks. The stiffness of the reinforcing steel is considered after the concrete has hardened, i.e. after the task CONCRETE or the calculation task HARDEN.
• The ultimate limit state occurs if any ultimate strain in the concrete, prestressing steel or reinforcing steel is reached.

Calculation assumptions for the checks in the SLS:

• Linear-elastic behavior of all materials except concrete under tension
• The concrete is assumed to be cracked, if the tensile stress exceeds the effective tensile strength fct,eff. In this case the tensile strength of the concrete is neglected.
• Transformed cross sections are considered (see above).
• The variations of the characteristic values of the prestressing force (rsup and rinf) according to EC 1992-1-1, 5.10.9 (1) are automatically considered. Note: For this purpose, it is necessary that all load cases/envelopes that are defined in the loading group “Prestressing” in the combination table are defined with the unfavorable/favorable factor 1.0 (see Combinations).