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

 

How to apply horizontal moving loads

 

As of now the Moving Load generator in STAAD.Pro can generate loads in vertical direction only. There is no automated facility to add horizontal loads to these generations. This feature would be implemented in a future STAAD.Pro version. For now as a temporary workaround, one can make use of notional loads to have these horizontal loads generated for each position of the moving load.

 

Here is an example of how this can be done. Let’s say there is a load case 100 which includes structure selfweight. It is followed by a moving load generation case which would generate 11 load combinations from 101 to 111

 

LOAD 100 LOADTYPE None TITLE SELFWEIGHT

SELFWEIGHT Y -1

LOAD GENERATION 11

TYPE 1 0 0 0 ZINC 1

 

…

 

Subsequently one can manually create additional cases ( using command editor ) where any of these generated load combinations can be combined with the horizontal load as shown below

…

LOAD 1001 LOADTYPE None TITLE LOAD CASE 1001

REPEAT LOAD

100 1.0 101 1.0

NOTIONAL LOAD

101 X 0.1

NOTIONAL LOAD

101 Z 0.1

 

The above load case 1001 is created by first combining the first of the generated combinations 101 with the selfweight load case 100. Horizontal loads ( Notional loads ) are then added by multiplying the load combination 101 by a factor of 0.1 and these are applied in X and Z directions simulating a longitudinal thrust and lateral thrust at the moving load location.

 

An example is attached uploaded below

 

communities.bentley.com/.../Structure1.std

 

There are a few factors that one needs to keep in mind though

1. The notional loads can only be generated at nodes. So if the generated moving load is not on a node but is on a beam, STAAD.Pro would calculate the notional load and apply it at the nearest node.
2. One can split the beams into segments to match with the increment in which the moving load is generated if one needs to generate these horizontal loads at exactly the vehicle locations.
3. One needs to use the editor to create these load cases combining the generated combinations with notional loads and there is no option in the GUI to do that.