Applies To
	Product(s):	STAAD.Pro
	Version(s):	ALL
	Environment:	ALL
	Area:	Modeling Solutions
	Subarea:	Loading
	Original Author:	Sye Chakraborty, Bentley Technical Support Group

 

I am running an analysis with moving load generation and see a series of messages like the one below in the analysis output file and moving load is not being generated
**WARNING-NO MEMBERS IN SPECIFIED VERTICAL RANGE.
What am I doing incorrectly ?

 

The warning messages mean that the moving load is applied at an elevation where there are no members to load. You may want to check the Y coordinate of the Initial Position of Load as shown in the next screenshot.

For example here the y coordinate for the initial position of the load is 10 ft. So the moving load generation tool will search for members at that Y elevation of 10 ft. If it so happens that your members are not at exactly Y=10 ft but these are at 10.05 ft (say) then the software would not find any members to load and would generate messages like the ones you encountered. In such cases you may want to use the Range option. For this specific example, using 0.1 ft as range (also marked in the picture above) would ensure that all members at 10.05 ft will be loaded by the moving load generation. In fact Y Range of 0.1 ft would mean that any members within the range of 10 ft and 10.1 ft would be loaded by the program.

he problem was that the Y elevation of the members were 1.98129 m whereas the point of application of the moving load was at Y=1.9812m. This minor difference in elevation was causing the moving load generation to fail. I have now included a range of 0.1 m to your moving load command so that it picks up any member within that 0.1 m range. A modified file is attached for your reference.

In terms of commands,
LOAD GENERATION 56 ADD LOAD 3
TYPE 2 15 10 0 ZINC 1 

would have to be changed to

LOAD GENERATION 56 ADD LOAD 3
TYPE 2 15 10 0 ZINC 1 YRANGE 0.1