RISA | Tips & Tricks

RISA | User Defined Maximum DCR in ADAPT-Builder

Written by RISA | May 24, 2022
 

ADAPT-Builder has historically been hard coded to design reinforcement for strength load combinations to a maximum demand/capacity ratio of 1.0. However, clients have expressed the want to be able to have the program reinforce to a user defined maximum DCR. ADAPT-Builder v21.0.1 includes the option to apply a user defined Maximum Demand/Capacity Ratio to design flexural reinforcement at a design section. The User Defined Maximum DCR can be used in any model and is available for all design codes.

In ADAPT-Builder 21.0.1 the user can modify the maximum flexural demand/capacity ratio the program is designing reinforcement to. Go to the Criteria ribbon and click on the Analysis/Design Option icon.

The Criteria window will open to the Analysis/Design Options. There is a new DC Ratio section within this window as shown in the image below.

To assign a user defined value click the radio button next to the User option. In the text box to the right of the User option, type in a new value for the maximum flexural design/capacity ratio you want to reinforce to. In the image below we have modified the input to be 0.95.

Once this is set you can analyze the model and design the design sections. Once the analysis and design have been completed you can double click a design section controlled by strength to see that the design capacity is now limited to the user defined demand/capacity ratio.

Notes:

  1. The code check for the support line design sections on plan, is hard coded to check if the maximum flexural demand/capacity ratio is less than 1.0. If the maximum flexural DC Ratio is less than 1.0 the program will show the design sections colored in green to indicate that they are passing the code check. For maximum flexural DC Ratio’s equal to or greater than 1.0 the program will color those sections pink with a dashed line to indicate they are failing.
  2. Total capacity is based on flexural and capacity due to compressive axial force (where applicable). Therefore, you may see some design sections showing values slightly above the default or the user-defined maximum flexural demand capacity ratio. The reason for the overage should be determined by the user if it is due to the increase in capacity from the slab having added capacity due to an axial compressive force in the slab. If the slab does have some added capacity due to compressive axial forces the section has the needed capacity, if this is not the case the reason for the overage should be determined and checked further.

For more information on the User Defined Maximum Demand/Capacity Ratio refer to the ADAPT-Builder Help File.