# Strange results for the 2D plane stress **URL:** \ **Category:** General Questions\ **Created:** [August 2, 2024, 7:37am UTC](https://prepomax.discourse.group/t/strange-results-for-the-2d-plane-stress/1920 "2024-08-02T07:37:08Z")\ **Posts on this page:** 1\ **Showing post:** 11
**Author:** ![Damn](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/damn/32/1539_2.png) [@Damn](https://prepomax.discourse.group/u/Damn)\ **Post date:** [August 5, 2024, 4:25pm UTC](https://prepomax.discourse.group/t/strange-results-for-the-2d-plane-stress/1920/11 "2024-08-05T16:25:20Z")
Sorry for the delay in my response; to check the functionality of the ENGINEERING CONSTANTS keyword, I prepared a model with a linear elastic material and, in parallel, an ENGINEERING CONSTANTS material with the three constants similar in the three directions and of a value similar to the first one. Apparently, unless I am mistaken, the both should lead to results that are not exactly the same but practically identical. Far from it, the results were really different. I saw this thread on the forum referencing the \*ORIENTATION and the ENGINEERING CONSTANTS keyword: > [@Timber modeling (engineering constants)](https://prepomax.discourse.group/t/timber-modeling-engineering-constants/1120/8): > > I have created 3 cubes, with the same material and loading and support conditions, but using ORIENTATION so that the greatest rigidity varies from one to another. And what I get is absolutely zero results. The problem comes from ORIENTATION, since if it is not included it does offer results (obviously the same in all 3 cases). Do you have any ideas about what I’m doing wrong? \*Material, Name=test \*Elastic,Type=ENGINEERING CONSTANTS 1000.0,500.0,500.0,0.2,0.2,0.3,500.0,500.0 250.0,20.0 \*Ori… Once the \*ORIENTATION keyword was introduced, the two models yielded practically similar results, which, from my point of view, was expected.I need to conduct many tests in this regard, but it seems like a good approach to simulate the behavior of wood in PrePoMax. I hope my comment has been helpful. --- _[View the full topic](https://prepomax.discourse.group/t/strange-results-for-the-2d-plane-stress/1920)._