diff --git a/docs/source/PDelta.rst b/docs/source/PDelta.rst index 9501152e..ae8484e6 100644 --- a/docs/source/PDelta.rst +++ b/docs/source/PDelta.rst @@ -1,5 +1,5 @@ ==================== -P-(U+0394) and P-(U+03B4) Analysis +P-:math:`{\Delta}` and P-:math:`{\delta}` Analysis ==================== When a structure is loaded, it displaces. Once a structure has displaced, the forces act on a geometry that is different than the geometry that was initially analyzed. Secondary forces develop due to eccentricities created by these displacements. These secondary forces are known collectively as P-(U+0394) and P-(U+03B4) effects. diff --git a/docs/source/stability.rst b/docs/source/stability.rst index ad24e8ca..77280e30 100644 --- a/docs/source/stability.rst +++ b/docs/source/stability.rst @@ -54,6 +54,6 @@ Once the Type 1 and Type 2 instabilities are rooted out of your model, there may Most material codes recognize that a first-order analysis is often not enough. As a structure deforms under load, the geometry changes, making the analysis results invalid. This requires us to reanalyze the structure under the new deformed geometry. -The P-(U+0394) analysis feature is one tool PyNite provides to help check for this type of instability. Additional considerations are usually necessary to capture this behavior, such as material stiffness reductions and notional loads. P-(U+0394) analysis is but one piece of the overall picture, which is usually defined by the material's building code. You can read more about P-(U+0394) :doc:`here `. +The P-(U+0394) analysis feature is one tool PyNite provides to help check for this type of instability. Additional considerations are usually necessary to capture this behavior, such as material stiffness reductions and notional loads. P-(U+0394) analysis is but one piece of the overall picture, which is usually defined by the material's building code. You can read more about P-(U+0394) :doc:`here `. Second order effects are usually only critical for models with slender members, or members with high axial loads in the presence of bending moments. If you don't have these types of features in your model, second order effects may be negligible. Consult your building code for specific criteria in making this determination. Either way, running a P-Delta analysis can help identify erorrs in the model you may have been unaware of. A model that cannot pass a P-Delta analysis is often something you don't really want to build.