A24 is selected. Shearwalls should be used.
The Complete Message:
Structural system type A24 (in X / Y direction) is selected. Shearwalls should be used in A24 structural systems.
A24 structural system is defined in the earthquake regulation as buildings where the moment-transferring ductility level of the earthquake effects are met by single-direction geared reinforced concrete frames with or without filling (hollow blocks) and reinforced concrete walls with high ductility level .
However, the shearwall is not defined in the project.
Possible solutions:
Shearwalls should be added in the direction requested in accordance with the A24 structural system in the project .
If shearwall will not be used in the building, A31 must be selected in the Analysis Settings / TBDY 2018 Earthquake Code Wizard. Bearing systems consisting of filled (filler) or unfilled single-direction geared reinforced concrete frames will be classified as structural systems with limited ductility level and will only be used in buildings with DTS = 3 and DTS = 4. (TBDY 4.3.4.3)