Please suggest whether the method adopted for assigning the impulsive mass and convective mass is correct or not. (SLAVE ZX MASTER 824 JOINT 212 TO 241) staad std. file attached

Please confirm whether the method adopted for assigning the Impulsive mass and Convective mass over an Overhead Tank is correct or not. (SLAVE ZX MASTER 824 JOINT 212 TO 241) staad std. file attached.

8838.STAAD File for Impulsive & Convective forces.zip

Method adopted :

IS-1893 (Part-II) requires Impulsive mass and Convective mass of  water to be applied at their respective CG's along with full mass of tank and 1/3rd mass of staging.

Also STAAD has limitation of allowing only 1 reference as mass load.

However, as per Fig-4 of IS-1893 (Part-II) , we have calculated the weighted distance of CG of mi & mc as ha=[hi.mi+hc.mc] /[mi+mc] and applied the total impulsive + convective mass at this ha along with full mass of tank and 1/3rd mass of staging. This is a work around over the STAAD limitation.

Added reference load in STAAD for following; 

  • Mass of Empty container  and  1/3 mass of staging.
  • Impulsive and convective mass at ha