3D Frame Spring Supports

[cancmm]

I am using SAP V14 Basic and am new to this particular program. The following is a hypothetical situation that is easier ot describe than my model but should address my question sufficiently.

Say I have a large circular pile cap supported on battered piles. The piles are spaced equally around the perimeter of the footing and are orientated such that they are battered radially outward from the center of the footing. The footing undergoes a large overturning moment, thereby inducing tension into some of the piles.

I would like to model the pile supports as linear springs, but rather than having 3 springs corresponding to the Global axes, I'd rather have only one in the pile's local (longitudinal) axis. In other words, the spring is inclined so it matches the batter angle of the pile.

What is the easiest way to accomplish this? Keep in mind, I have a lot of springs to model and changing the local axis of each supporting joint would be extremely tedious. In STAAD, I could assign the spring support to the local axis of the pile, rather than the joint itself. This was much easier than any methods I can conjur up with SAP.

Appreciate any input!

 

[masomenos]

You can rotate the local axes of multiple joints in one command fairly easily by selecting them then Assign>Joint>Local axis then checkbox "advanced". There you have several options such as user vector or specify two joints or plane coordinate direction CR CA in order to line up with frame local axis. You don't have to rotate joints one-at-a-time. The advanced option joint local axis also makes it easy to orient local joint axis with shell local axes if you're working with tanks/vessels.

 

[cancmm]

Thanks but I don't think this solves my problem. Each joint has a different local axis/plane. Therefore, I'd have to select each joint and assign a vector for each. Ideally, there would be an option to simply match the local coordinates to the supporting member, rather than needing to define the local coordinate system from scratch. This is what STAAD did and I found it much more convenient.

 

[masomenos]

Not true. I just defined battered piles with 20 joints and assigned multiple local axes on joints to match frame local axis using the instructions I posted earlier. It took me less than a minute to do it. Spend a little time experimenting with joint local axis 'advanced' options if you're willing to learn.