I would like to model a tendon that is pinned at the top to the OWT support structure, and connected to a pile anchor through a universal joint at the bottom.
What is did is the following (in sudyn)
- STRUCTURE JOINTS: Joint 20 is type 3 (Pin), with JointDirX 0, JointDirY 1.0 and JointDirZ 0.0, JointStiff 0.0
- STRUCTURE JOINTS: Joint 25 is type 2 (Universal), with JointDirX 1.0, JointDirY 1.0 and JointDirZ 0.0, JointStiff 0.0
- BASE REACTION JOINTS:
RctRDXss' and-Yss` to 0
MemberID 24, MJointID1 20, MJointID2 25, MPropSetID1 1, MPropSetID2 1, MType 2
- CABLE PROPERTIES:
PropSetID 1 EA 1.489719e+10 MatDens 533.3242, T0 6280e+3 CtrlChannel 0
When I try to run the case, at the beginning I got this error:
Node 25 is an universal joint, number of members involved: 1
FAST_InitializeAll:SD_Init:DirectElimination:BuildTMatrix:JointElimination: universal joints should only connect two elements.
Based on Link:
This version of SubDyn can, in fact, handle partially restrained joints by setting one or more DOF flags to 0 and providing the appropriate stiffness and mass matrix elements for that DOF via the SSIfile
I therefore added a “SSI.txt” file in the BASE REACTION JOINT for RJointID 25, that looks like the following, but I still have the same error.
Where is my mistake?
!---------------- Pile Head K and M elements -------------------!
!Equivalent Stiffness Constants: Kxx, Kyy, Kzz, Kxtx, Kxty..Kztx,Kzty,Kztz in any order; max 21 elements