**ERROR: BASE DIMENSION SEEMS IMPROPER. PROGRAM CALCULATES BASE

Question

please check error. 8272.Structural Staircase-3-1.STD

Shreyanka Bhattacharjee · Answer

You are using ST 5 parameter. To calculate the time period of these type structures (ST 5), program needs the base dimension along both plan direction at lowest support level. 
 In this structure, program could not find any nodes along Z direction at the lowest support level to calculate the base dimension. 
 Program calculates the time period along X direction taking the Base dimension 1.5 m. 
 
 Please use PZ parameter (Time period along Z direction).