Multispring contact modelling

Hi All,
Can someone help me for modelling multispring contact element to represent the rocking behaviour of precast column member (in connection with beam and foundation) ?
I came to know from Spieth et al (2004) that we can model such behaviour using multispring contact element. However, I am confused with the type of element. Wondering it is either to model as a spring element or contact element .
It would be very much appreciable if someone help me in this matter.

Bidur

This element uses a series of parallel springs to represent a filament model of the contact. Generally advised to use a minimum of 8 springs and if modelling a rocking contact connection (hybrid joint) then use the bi-linear with gap hysteresis. As the spring has a axial flexibility the axial flexibility of the column member above need to be reduced so that the total axial flexibility from the floor above to the column base is correct. Ensure that the gravity load acts on the multispring as a compressive load or the structure will have no vertical stiffness if total lift-off is possibel.

Hi Athol,
Thank you for your reply clarifying about the multispring.
The problem is that I could not find such element (Multispring) in RUAUMOKO manual that we have got (It is of 2003 version). Can you please further say me If this element has been included later on in the program and in user manual as well ?
If so, how can I get the detail of such element ( I mean guide to prepare input file for such element like frame, spring element) ?

Thank you.

Bidur

This element appeared in the program about 2004 and is in manuals since then. The Rose School has the latest manuals, only available as .pdf files.

Hi Athol,
I am just wondering how can we get a latest version of Program RUAUMOKO and its's user manual which has MULTISPRING element included. We have got institutional license ( I think It was of 2003).
Do we need to pay and order a new version? or we can get it free ?

Thank you very much in advance.

Regards,
Bidur

Hi Bidur,
If your university has a full license then they can easily get the latest version, the contact need to email me to ask. The Rose School has a version that is only about 6 months old. I do not use version numbers, the program is always getting new features so would be out-of-date in a week. The compilation date is shown at the beginning of the output file which thus indicates when the version you are working from was made.. There is a student version available limited to the 2D version with a maximum of 25 nodes. The student version is free but I need a postal address to send the cdrom.

Hi ALL,
Can someone please send me an example input file which has got multispring element in it ? I am confused with selecting the different parameter for it.
Your help will be much appreciated.

Bidur