Design

Design of reinforcement

First you get an overview of the input data for the design:

• Internal forces, displaying the characteristic and design values.
  
  For member type 'column', the design values of the bending moments include the 2^nd order bending moments (if required) and the moments due to geometric imperfections.
  
  For member type 'beam', the design values of the bending moments include the shifting of the moment line - to take the additional tensile force due to shear into account.

• Slenderness calculation (for member type 'column'), determining if 2^nd order effects need be taken into account.

Longitudinal reinforcement

The design of longitudinal reinforcement to resist N, M_y and M_z is done according to the Ultimate Limit State requirements. Design method is selected based on type of member (beam x column) and according to the acting load. There is not any limit for type of cross-section (formerly for columns rectangle and circle) nor for load type (formerly for beams - M_y or M_z).

In case the required area of reinforcement exceeds the available space on one layer, more layers (with adapted lever arm) are automatically generated. Designed reinforcement is automatically recalculated to real bars afterwards.

Shear reinforcement

The design of shear reinforcement to resist V_y and V_z is done according to the ULS requirements. Formerly, there was possibility to design shear reinforcement just for V_y or V_z.

 

Terminology:

Statically required reinforcement A_s,stat – it is reinforcement designed by the program (reinforcement for N+My+Mz, longitudinal reinforcement designed for tensile force caused by shear and torsion)

Required reinforcement A_s,req – it is sum of statically required reinforcement and reinforcement designed according detailing provisions

Basic provided reinforcement A_s,bas,prov – it is predefined reinforcement by the user in Concrete setting or concrete member data. This reinforcement is constant at whole length of the member.

Additional provided reinforcement A_s,add,prov – it is predefined additional reinforcement by the user in Concrete setting or concrete member data and these reinforcement will be used only on parts of the member where basic reinforcement is not sufficient.

Additional required reinforcement A_s,add,req – it is reinforcement designed by the program, calculated as difference between required reinforcement and provided reinforcement

A_s,add,req = A_s,req - A_s,prov = A_s,req - A_s,bas,prov - A_s,add,prov

Provided reinforcement A_s,prov – it is reinforcement calculated as sum of basic provided and additional provided reinforcement A_s,prov = A_s,bas,prov + A_s,add,prov