Multiple support specifications in single STAAD model

[cyclemaniac]

It is possible to have multiple support specifications in a single STAAD model. The first instance of each support prior to the first load case must have the same or more degrees of freedom as subsequent specifications of the same support.

Define support
Define load case 1 (for example)
Perform analysis
Change
Redefine support specifications
Define Load Case 2
Perform Analysis

So if the first load is a dead load case and you wish to insure that all lateral forces are zero the support would be defined as "fixed - but" with very weak springs in lateral directions for load case 1

SUPPORTS
1 FIXED BUT MX MY MZ KFX .0005 KFZ .0005 (ONLY y ACTIVE)
LOAD CASE 1 DEAD LOAD
(DEFINE LOAD PARAMETERS)
PERFORM ANALYSIS (THIS CREATES RESULTS WITH SUPPORT AS INDICATED)
CHANGE
SUPPORTS
1 FIXED BUT MX MY MZ (FX, FY ,FZ ACTIVE NOW)
LOAD CASE 2 WIND LOAD
ETC.....