joint pattern loads

[par060]

I am new with the joint pattern feature in version12. It seems like when I assign a pattern....and give it a wt. per unit volume.....and then give it an additional unit load...I would get that unit load times the distance below my datum(in this case zero)plus the additional load...assuming when I assign the load to an area connecting those joints, I choose the joint pattern and a muliplier of 1.

I test this by useing a square area with 4 supports and then checking my reactions they don't come out that way

 

[IJR]

par060

Joint patter is simply an equation that determines pressure at a distance Z from some lowest point.

1-Sketch the distance Z axis on paper
2-manually determine the pressure at some initial point, ie a point with low Z coordinate(this does not have to be Z=0, i
t could be z=-100 even)
3-Manually determine the pressure at the topmost point
4-Now write the equation given in Sap2000,substitute the two pressure values, and solve the equation to determine the coefficients
5-Go back to the model and see if SAP got the two extreme values right.

respects
IJR

 

[par060]

Thanks IJR...I found my problem...you really need to be careful when assigning loads in this way to be sure you always have the correct pattern name selected and note that the default selection is to "add to existing loads"...