AD.2007-03.2.1 Selfweight Command with a Member List

When considering stage construction, it is occasionally necessary to create load cases which include the effects only of the additional parts of structure. In order to do this the SELFWEIGHT command has been enhanced to allow a member list to be added which will be processed and only selfweight on that list will be considered.

This command may be used to calculate and apply the SELFWEIGHT of the structure for analysis. This allows you to enter body weight of the structural components. In other words, it allows different parts of the structure to be excited with different accelerations.

Refer to TR.32.9 Selfweight for details on using member lists with the Selfweight command.

Example

LOAD 1 DEAD AND LIVE LOAD
SELF WEIGHT X 1.4 LIST 4 TO 10
SELF X 1.0 _PLATEGRP1
SELF 
SELF Y -1.4
SELF X 1.4 ALL
SELF WEIGHT Z 1.4 _SOLIDGRP1
SELF Y -1.4 YR 10.5 10.51
SELF Y -1.4 X

In above example, the first specification includes factored weight of member (/plate/solid) 4 through 10 along global X direction and the second includes weight of all members (/plates/solids) associated with group _PLATEGRP1. The third command includes weight of all structural components towards gravity direction (SELF WEIGHT Y -1.0).

SELFWEIGHT specification for definition of static method of seismic load generator also is capable of accepting list. Only there is no direction specification for this command.

Similarly, the SELFWEIGHT specification when used in a Reference Load is also capable of handling a list.