# Truss element one direction **URL:** \ **Category:** Uncategorized\ **Created:** [May 12, 2023, 10:09pm UTC](https://calculix.discourse.group/t/truss-element-one-direction/1653 "2023-05-12T22:09:47Z")\ **Posts on this page:** 4\ **Page:** 2
**Author:** ![Disla](https://yyz2.discourse-cdn.com/free1/user_avatar/calculix.discourse.group/disla/32/3548_2.png) [@Disla](https://calculix.discourse.group/u/Disla)\ **Post date:** [May 15, 2023, 10:39am UTC](https://calculix.discourse.group/t/truss-element-one-direction/1653/21 "2023-05-15T10:39:15Z")
| Spring Elongation | Z | = | 3.952 | mm | | --- | --- | --- | --- | --- | | Spring Tension Force | Fz | = | 259,372 | N | | | | | 259.4 | KN | I’m using an auxiliary dummy element to masure the elongation of the spring. ![imagen](https://global.discourse-cdn.com/free1/uploads/calculix/original/2X/d/d85c52ee2e2053b8f2644bb046483d339748c63a.png) EDITED: Oh Sorry This is for a displacement of 5mm. I see you have change your BC in the last post to a load of 900N . | Elongation | Z | = | 0.0137143 | mm | | --- | --- | --- | --- | --- | | Spring Tension Force | Fz | = | 900 | N | | | | | 0.9 | KN | ![imagen](https://global.discourse-cdn.com/free1/uploads/calculix/original/2X/f/f0e5e8889683c1d194cc7e8d00d635395853bc4e.png) ---
**Author:** ![dichtstoff](https://avatars.discourse-cdn.com/v4/letter/d/dec6dc/32.png) [@dichtstoff](https://calculix.discourse.group/u/dichtstoff)\ **Post date:** [May 15, 2023, 11:10am UTC](https://calculix.discourse.group/t/truss-element-one-direction/1653/22 "2023-05-15T11:10:50Z")
thnx for your help, Disla i see, that spring constante is necessary value for SPRINGA. i have now displacement 0.01372 and with spring constant, and with the relativ displacement i get my force. ok thnx for your help. I know why i prefere a truss element !!! I will check if i can use \*RIGID BODY with truss and or springa element, to connect the surface instead only one node!? Is it possible, to use truss element with the one-node 3-dimensional spring (SPRING1) element? 🙂 two more questions: can i use in ccx also these auxiliary construction with the dummy element? and if i read out the result with a fbd file, i can not see my springa element? read SPRINGA.frd read SPRINGA.inp nom plot e ESPRINGA wbr & thanx a lot ---
**Author:** ![Disla](https://yyz2.discourse-cdn.com/free1/user_avatar/calculix.discourse.group/disla/32/3548_2.png) [@Disla](https://calculix.discourse.group/u/Disla)\ **Post date:** [May 15, 2023, 11:58am UTC](https://calculix.discourse.group/t/truss-element-one-direction/1653/23 "2023-05-15T11:58:27Z")
> [@dichtstoff](#): > > with spring constant, and with the relativ displacement i get my force. Right. Maybe someone knows a ccx comand to get the tension on the spring directly but I’dont. I need to measure elongation and then extract the Force form simple interpolation on the curve. > [@dichtstoff](#): > > I know why i prefere a truss element Why? You have the same problem ¿isn’t it?. You comment you also need to measure the force inidectly through the stress\*Area. > [@dichtstoff](#): > > can use \*RIGID BODY I don’t see why not. The spring will go from REF node to REF NODE. > [@dichtstoff](#): > > dimensional spring (SPRING1) > [@Is nonlinear stiffness allowed for SPRING1 elements?](https://calculix.discourse.group/t/is-nonlinear-stiffness-allowed-for-spring1-elements/412/6): > > I have managed to set up a nonlinear SPRING1 element. I’m imposing a sinusoidal vertical displacement to test the whole positive and negative response range. Reactions follow the Force-Elongation shape but values for the reaction forces are wrong. Should be Rz=504=200N I get Rz=1254=500N For prescribed displacements it gives this warning but ccx can finish the analysis: “\*INFO in cascade: linear MPCs and nonlinear MPCs depend on each other common node: … ---
**Author:** ![Disla](https://yyz2.discourse-cdn.com/free1/user_avatar/calculix.discourse.group/disla/32/3548_2.png) [@Disla](https://calculix.discourse.group/u/Disla)\ **Post date:** [May 15, 2023, 12:06pm UTC](https://calculix.discourse.group/t/truss-element-one-direction/1653/24 "2023-05-15T12:06:05Z")
> [@dichtstoff](#): > > dummy element To measure the elongation is tricky and get it plotted on screen too. I will post how I have solved it in Mecway so I don’t have to write twice. > [@dichtstoff](#): > > i can not see my springa element About visualization, I don’t know why you don’t see it sorry. [Previous page](https://calculix.discourse.group/t/truss-element-one-direction/1653.md?page=1)